Ovarian activity, hormone profile, pro-inflammatory cytokines and reproductive performance of buffalo cows fed diets with different estrogenicity

Buffalo cows play a vital role in milk and meat production; however, they are characterised by several reproductive disorders. Feeding diets with high oestrogenic activity may be a disrupting factor. This study aimed to evaluate the effects of feeding roughages with different oestrogenic activity on the reproductive performance of early postpartum buffalo cows. A total of 30 buffalo cows were equally stratified into two experimental groups and fed either Trifolium alexandrinum (Berseem clover, phytoestrogenic roughage) or corn silage (nonoestrogenic roughage) for 90 consecutive days. After 35 days from the beginning of the feeding treatments, buffalo cows in both groups were synchronized for oestrus using a double i.m. injection of 2 mL prostaglandin F2α , 11 days apart, subsequently, overt signs of oestrus were observed and recorded. Moreover, ovarian structures, numbers and sizes of follicles and corpora lutea, were ultrasonography examined at day-12 (represents Day 35 of feeding treatment), Day 0 (day of oestrus) and Day 11 after oestrous synchronization (mid-luteal phase). Pregnancy was diagnosed 35 days postinsemination. Blood serum samples were analysed for progesterone (P4 ), estradiol (E2 ), tumor necrosis factor (TNF-α), interlukein-1β (IL-1β) and nitric oxide (NO). The high performance liquid chromatography-analysis of roughages showed the abundance of isoflavones in Berseem clover, with about 58 times higher concentration than that in corn silage group. During the experimental period, the numbers of ovarian follicles of all size categories were higher in the Berseem clover group than that in the corn silage group. No significant difference in the numbers of corpora lutea was observed between both experimental groups, but lower (p < 0.05) diameter of corpus luteum was observed in the Berseem clover group than that in the corn silage group. The Berseem clover group had higher (p < 0.05) overall concentrations of blood serum E2 , IL-1β and TNF-α, but lower (p < 0.05) overall concentrations of blood serum P4 than those recorded in the corn silage group. Oestrous rate, onset of oestrus time and oestrous duration were not significantly affected by the treatment. The conception rate was significantly (p < 0.05) reduced in the Berseem clover group compared with that in the corn silage group. In conclusion, feeding roughage with a high oestrogenic activity such as Berseem clover can negatively affect the conception rate of buffalo cows. This reproductive loss seems to be associated with inadequate luteal function and P4 concentration during early pregnancy.

Effects of Different Galacto-Oligosaccharide Supplementation on Growth Performance, Immune Function, Serum Nutrients, and Appetite-Related Hormones in Holstein Calves

Our previous study showed that early supplementation with 10 g/(d·head) of galacto-oligosaccharides (GOS) in newborn Holstein dairy calves reduced the incidence of diarrhea and improved growth performance and mineral absorption. Since the dose of 10 g/(d·head) was the lowest by dose screening in our previous study, the present study was designed to investigate whether a lower amount of GOS has similar effects on growth performance, immune function, serum nutrients in newborn Holstein heifer calves, and to further investigate its effect on appetite-related hormones. Twenty-eight healthy newborn (1 day of age) Holstein heifers with similar average body weight (41.18 ± 1.90 kg) were randomly divided into four groups (n = 7): the control group (CON group), which received heated raw milk, and three experimental groups, which received heated raw milk supplemented with 2.5 (GOS2.5 group), 5 (GOS5 group), and 10 g/(d·head) (GOS10 group) GOS. All heifer calves were fed the same starter for 28 d. Supplementation with GOS linearly increased the final body weight, average daily gain, and feed efficiency in heifer calves (p < 0.01). Compared with the control group, the average daily gain and feed efficiency of heifer calves were significantly higher in the GOS5 and GOS10 groups than in the control group (p < 0.05). Furthermore, supplementation with GOS quadratically enhanced the starter and total average daily feed intake of the heifers (p < 0.01), especially in the GOS2.5 and GOS5 groups, (p < 0.05 vs. CON). The serum concentration of immunoglobulin A was linearly increased by GOS supplementation (p < 0.05), and the levels in the GOS5 and GOS10 groups were significantly higher than those in the CON group. Meanwhile, GOS linearly decreased serum interleukin-1β and interleukin-6 concentrations (p < 0.05). The serum concentration of triglycerides was also linearly decreased (p < 0.05), whereas total protein and blood urea nitrogen were linearly increased (p < 0.05). Supplementation with GOS linearly decreased the serum concentration of leptin (p < 0.05) but increased cholecystokinin and glucagon-like peptide-1 (p < 0.05). Increasing doses of GOS linearly improved serum calcium and copper concentrations (p < 0.01) and quadratically enhanced the concentration of magnesium, which peaked in the GOS5 group (p < 0.05). In conclusion, GOS supplementation reduced the incidence of diarrhea and improved the growth performance and immune function of Holstein heifer calves.

Early supplementation with zinc proteinate does not change rectal microbiota but increases growth performance by improving antioxidant capacity and plasma zinc concentration in preweaned dairy calves

The present study evaluated the effects of early supplementation with zinc proteinate (ZnP) or zinc oxide (ZnO) for 2 weeks on the growth performance, redox status, plasma trace element concentrations, and rectal microbiota of preweaned dairy calves. A total of 60 newborn healthy female Holstein dairy calves, with initial body weight (BW): 41.33 ± 0.62 kg, were randomly allocated to 5 groups of 12 each: a control group (CON); three groups supplemented with 261 (L-ZnP), 523 (M-ZnP), and 784 (H-ZnP) mg/day ZnP, equivalent to 40, 80, and 120 mg/day zinc, respectively; and one group supplemented with 232 mg/day ZnO, equivalent to 180 mg/day zinc (ZnO). Zinc supplements were administered on days 1-14, and the calves were followed up until day 70. Zinc supplementation increased total dry matter intake (DMI) and starter DMI compared with the CON group (p < 0.01). The final BW, average daily gain, and feed efficiency were higher in the M-ZnP, H-ZnP, and ZnO groups (p < 0.05). The incidence of diarrhea on days 1-28 was reduced by zinc administration (p < 0.01), whereas the incidence on days 29-56 was lower in the M-ZnP and ZnO groups (p < 0.05). Serum glutathione peroxidase activity, total antioxidant capacity, immunoglobulin G and plasma zinc concentrations were increased linearly (p < 0.05), while the serum concentration of malondialdehyde was decreased linearly (p < 0.01), as the dose of ZnP increased. ZnP yielding 80 mg/day zinc had similar effects as ZnO yielding 180 mg/day zinc, except that final BW was higher in the ZnO group (p < 0.05). At the phylum level, ZnO decreased the relative abundance of Firmicutes while increasing the abundance of Bacteroidetes (p < 0.05). At the genus level, ZnO increased the relative abundances of Prevotella, Subdoligranulum, and Odoribacter (p < 0.05). These findings indicated that early supplementation with ZnP did not affect the rectal microbiota of preweaned dairy calves but increased their growth performance, antioxidant capacity, and plasma zinc concentration. In summary, ZnP is an organic zinc source with greater bioavailability than ZnO for preweaned dairy calves. Early dietary supplementation with ZnP yielding 80 mg/day zinc is recommended.

Coat color affects the resilience against heat stress impacts on testicular hemodynamics, reproductive hormones, and semen quality in Baladi goats

Drastic climatic changes threaten animal productivity and prolificacy, whose adaptability is governed by its pheno- and genotypic traits. This study was aimed at investigating the effect of coat color on the adaptability of goat bucks under heat stress conditions from the perspectives of testicular blood flow (TBF) and biometry, reproductive hormones, and semen quality. Twenty bucks (Capra hircus) bearing different coat colors were selected from a large flock and divided into four equal groups (n = 5 each) as follows: black coat (BC; 100% black), brown coat (BrC; 100% dark brown), white coat (WC; 100% white), white-black coat (WBC; 50-60% white). Bucks were examined for TBF [Doppler ultrasonography and serum nitric oxide (NO)], testosterone (T) and luteinizing hormone (LH), seminal plasma oxidative biomarkers [catalase (CAT), total antioxidant capacity (TAC), and malondialdehyde (MDA)], and sperm traits percentages [progressive motility (PM), viability (SV), normal morphology (NM), and sperm concentration (SC) once a week for seven consecutive weeks (W1-W7) in the summer season (temperature humidity index = 88.4-92.2). Specifically, at W3-W7, darker bucks (BC and BrC) testicular volume, testicular colored area, T, NO, CAT, TAC, PM, SV, NM, and SC (W7 only) differed significantly (P < 0.05) by decrease than the lighter ones (WC and WBC). Both Doppler indices and serum MDA concentrations were elevated (P < 0.05) at W3-W7 in the BC and BrC bucks compared to WC and WBC groups. In conclusion, bucks with lighter coats were more resistant to the negative effects of HS on TBF, seminal oxidative biomarkers, and semen quality.

Alginate Nanoencapsulated Synbiotic Composite of Pomegranate Peel Phytogenics and Multi-Probiotic Species as a Potential Feed Additive: Physicochemical, Antioxidant, and Antimicrobial Activities

A synbiotic composed of alginate nanoencapsulated prebiotic (pomegranate peel phytogenics) and multi-species probiotics (Lactococcus lactis, Lactobacillus plantarum, Lactobacillus paracasei, and Saccharomyces cerevisiae) has been developed as a potential eco-friendly alternative to antibiotics. The physicochemical properties of the encapsulated synbiotic were evaluated, and its gastric and storage tolerance, as well as its antioxidant and antimicrobial activity, were tested and compared to that of the non-encapsulated synbiotic (free synbiotic). The results showed that the prebiotic pomegranate peel ethanolic extract contained seven phenolic compounds, with cinnamic being the most abundant (13.26 µL/mL). Sodium alginate-CaCl2 nanocapsules were effective in encapsulating 84.06 ± 1.5% of the prebiotic's phenolic compounds and 98.85 ± 0.57% of the probiotics. The particle size of the alginate-CaCl2 nanoencapsulated synbiotic was 544.5 nm, and the polydispersity index and zeta potential values were 0.593 and -12.3 mV, respectively. Thermogravimetric analysis showed that the alginate-CaCl2 nanoencapsulated synbiotic had high thermal stability at high temperatures, with only 2.31% of its weight being lost within the temperature range of 70-100 °C. The count of viable probiotics in the nanoencapsulated synbiotic was significantly higher than that in the free synbiotic after exposure to gastric acidity and storage for six months at room temperature. The percent inhibition values of the nanoencapsulated synbiotic and ascorbic acid (as a standard antioxidant) were comparable and significantly greater than those of the free synbiotic. The half-maximal inhibitory concentrations (IC50) of the nanoencapsulated synbiotic and ascorbic acid were significantly lower than those of the free synbiotic (3.96 ± 0.42 µg/mL and 4.08 ± 0.79 µg/mL for nanoencapsulated synbiotic and ascorbic acid, respectively, vs. 65.75 ± 2.14 µg/mL for free synbiotic). The nanoencapsulated synbiotic showed the highest significant antimicrobial activity against Escherichia coli (ATCC 8739). Both the nanoencapsulated and free synbiotics showed antimicrobial activity against Staphylococcus aureus (ATCC 6538), similar to that of gentamicin, although the nanoencapsulated synbiotic showed significantly higher inhibition activity compared to the free synbiotic. The nanoencapsulated synbiotic showed antimicrobial activity comparable to gentamicin against Pseudomonas aeruginosa (ATCC 90274), whereas the free synbiotic showed the least antimicrobial activity (p < 0.05). Both synbiotics showed significantly higher antimicrobial activity against Salmonella typhi (ATCC 6539) than gentamicin. Both synbiotics showed antifungal activity against Aspergillus niger and Aspergillus flavus, with a stronger effect observed for the nanoencapsulated synbiotic. However, the activity of both synbiotics was significantly lower than that of fluconazole (an antifungal drug).

Struggling Thermal Stress Impacts on Growth Performance and Health Status of Newly Weaned Rabbits Using Nanoemulsion of Origanum majorana Considering the Economic Efficiency of Supplementation

With the recent trend of global warming, HS-instigated diminishing could extremely jeopardize animal health, productivity, and farm profit. Marjoram essential oil (MEOE) is a worthy source of wide range phytogenic compounds that may improve heat tolerance, redox and inflammatory homeostasis, and immunity of newly weaned rabbits, specifically if included in the diets in a nano form. One hundred newly weaned rabbits were randomly distributed into four homogeneous groups. The first group (control group) included rabbits that received basal diet without supplementation. In contrast, the other three groups included rabbits that received basal diets supplemented with 200 (MEONE200), 400 (MEONE400), and 800 (MEONE800) mg MEONE/kg diet, respectively. Among MEONE-treated groups and control groups, MEONE400 group showed the highest (p < 0.001) growth performance traits, including final body weight, average daily gain, feed efficiency, and the performance index. Compared to the control, all MEONE-supplemented groups possessed lower rectal temperatures and respiration rates, recording the lowest values in the MEONE400 group. The oxidative stress biomarkers and immunoglobulins G and M were significantly improved in the MEONE400 and MEONE800 compared with the control and MEONE200 groups. The addition of MEONE (400 or 800 mg/kg) decreased the concentrations of serum interleukin-4 (p = 0.0003), interferon gamma (p = 0.0004), and tumor necrosis factor-α (p < 0.0001) but significantly elevated (p < 0.001) the activity of nitric oxide, amyloid A and lysozyme. Liver functions (lower concentrations of liver enzymes) were significantly improved in all MEONE-treated groups compared to the control group. There was a considerable significant effect of dietary supplementation of MEONE400 on economic efficiency. In conclusion, the addition of 400 mg/kg to the diets of newly weaned rabbits can be recommended as an affective intervention to mitigate the negative impacts of HS.

Melatonin administration during the first half of pregnancy improves the reproductive performance of rabbits: Emphasis on ovarian and placental functions

This study was designed to investigate the roles of melatonin administration during different sensitive windows of the first half of pregnancy in the function and gene expression of the ovary and placenta, hormone profile, and pregnancy outcomes in rabbits. Four equal experimental groups of 20 rabbits each were used. The first (FW), second (SW), and third (F + SW) groups comprised rabbits that orally received 0.7-mg melatonin/kg body weight during the first week, second weeks, and during both weeks of pregnancy; and the fourth group served as the control group (C). The total number of visible follicles significantly increased in all melatonin-treated groups compared with that in the C group. In all melatonin-treated groups, the number of absorbed fetuses was significantly reduced, whereas the weights of embryonic sacs and fetuses were higher than in the C group. The placenta efficiency was significantly increased in the F + SW group compared with that in the C group, followed by the SW group, whereas no significant difference in the placenta efficiency was found between the FW and C groups. Melatonin treatments significantly improved the expression of antioxidants, gonadotropin receptors, and cell cycle regulatory genes in the ovary, whereas only FW treatment upregulated steroidogenic acute regulatory gene. Compared with the C and FW groups, melatonin treatments during the SW and F + SW significantly upregulated the expression of most genes in the placenta. The concentrations of estradiol were significantly higher in the SW and F + SW groups than in the FW and C groups. The concentrations of progesterone were significantly increased in the FW group compared with those in the C and SW groups, whereas the F + SW group showed intermediate values. The litter size and weight at birth significantly increased in all melatonin-treated groups compared with those in the C group. The second week of pregnancy seems to be a sensitive window for melatonin actions during pregnancy. Thus, melatonin administration during the second week of pregnancy can be effective in improving pregnancy outcomes in rabbits.

Antioxidants status and physiological responses to early and late heat stress in two rabbit breeds

Early life heat stress negatively affects rabbit production and well-being. However, the physiological response to acute heat stress in later life is not clearly defined. The present study aims to investigate the effects of early and late heat stress at 36°C on some blood constituents, antioxidant enzymes activity in the blood, and muscle in New Zealand white and Baladi Black rabbits. A total of sixty post-weaning rabbits of each breed were randomly divided into two groups; control groups (NZWC and BBC) and early heat-stressed groups for six hours at 36 ± 1°C and 62% relative humidity (RH) (NZWT and BBT groups). After heat stress, six rabbits from each group were slaughtered for blood and muscle tissue collection. The surviving rabbits were kept at 28 ± 1°C and 40% RH till 13 weeks of age. At the end of 13 weeks, all rabbits were exposed to late heat stress as precious described to perform four groups: single late stressed groups; NZWC2, BBC2, and double stressed groups; NZWT2 and BBT2. After late heat stress, six rabbits from each group were slaughtered for blood and muscle tissue collection. The early and late heat stress caused a significant reduction in the blood creatine kinase, lactate dehydrogenase, and high-density lipoprotein and antioxidant enzymes' activity in blood and muscle of both NZW and BB rabbits compared with the control groups. While, the blood total cholesterol, triglycerides, total lipids levels, and lipid peroxidation activity in blood and muscle were significantly increased due to the early and late heat-stressed both breeds compared with the control groups. It could be concluded that the early heat stress at 36°C has negative effects on several physiological indicators and antioxidant activities in the blood and muscle of NZW and BB rabbits.

Genome centric engineering using ZFNs, TALENs and CRISPR-Cas9 systems for trait improvement and disease control in Animals

Livestock is an essential life commodity in modern agriculture involving breeding and maintenance. The farming practices have evolved mainly over the last century for commercial outputs, animal welfare, environment friendliness, and public health. Modifying genetic makeup of livestock has been proposed as an effective tool to create farmed animals with characteristics meeting modern farming system goals. The first technique used to produce transgenic farmed animals resulted in random transgene insertion and a low gene transfection rate. Therefore, genome manipulation technologies have been developed to enable efficient gene targeting with a higher accuracy and gene stability. Genome editing (GE) with engineered nucleases-Zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) regulates the targeted genetic alterations to facilitate multiple genomic modifications through protein-DNA binding. The application of genome editors indicates usefulness in reproduction, animal models, transgenic animals, and cell lines. Recently, CRISPR/Cas system, an RNA-dependent genome editing tool (GET), is considered one of the most advanced and precise GE techniques for on-target modifications in the mammalian genome by mediating knock-in (KI) and knock-out (KO) of several genes. Lately, CRISPR/Cas9 tool has become the method of choice for genome alterations in livestock species due to its efficiency and specificity. The aim of this review is to discuss the evolution of engineered nucleases and GETs as a powerful tool for genome manipulation with special emphasis on its applications in improving economic traits and conferring resistance to infectious diseases of animals used for food production, by highlighting the recent trends for maintaining sustainable livestock production.

Potential of montmorillonite modified by an organosulfur surfactant for reducing aflatoxin B1 toxicity and ruminal methanogenesis in vitro

Background

Montmorillonite clay modified by organosulfur surfactants possesses high cation exchange capacity (CEC) and adsorption capacity than their unmodified form (UM), therefore they may elevate the adverse impact of aflatoxin B1 (AFB1) on ruminal fermentation and methanogenesis. Chemical and mechanical modifications were used to innovate the organically modified nano montmorillonite (MNM). The UM was modified using sodium dodecyl sulfate (SDS) and grounded to obtain the nanoscale particle size form. The dose-response effects of the MNM supplementation to a basal diet contaminated or not with AFB1 (20 ppb) were evaluated in vitro using the gas production (GP) system. The following treatments were tested: control (basal diet without supplementations), UM diet [UM supplemented at 5000 mg /kg dry matter (DM)], and MNM diets at low (500 mg/ kg DM) and high doses (1000 mg/ kg DM).

Results

Results of the Fourier Transform Infra-Red Spectroscopy analysis showed shifts of bands of the OH-group occurred from lower frequencies to higher frequencies in MNM, also an extra band at the lower frequency range only appeared in MNM compared to UM. Increasing the dose of the MNM resulted in linear and quadratic decreasing effects (P < 0.05) on GP and pH values. Diets supplemented with the low dose of MNM either with or without AFB1 supplementation resulted in lower (P = 0.015) methane (CH₄) production, ruminal pH (P = 0.002), and ammonia concentration (P = 0.002) compared to the control with AFB1. Neither the treatments nor the AFB1 addition affected the organic matter or natural detergent fiber degradability. Contamination of AFB1 reduced (P = 0.032) CH₄ production, while increased (P < 0.05) the ruminal pH and ammonia concentrations. Quadratic increases (P = 0.012) in total short-chain fatty acids and propionate by MNM supplementations were observed.

Conclusion

These results highlighted the positive effects of MNM on reducing the adverse effects of AFB1 contaminated diets with a recommended dose of 500 mg/ kg DM under the conditions of this study.

Nanodelivery System for Ovsynch Protocol Improves Ovarian Response, Ovarian Blood Flow Doppler Velocities, and Hormonal Profile of Goats

Fifteen cyclic, multiparous goats were equally stratified and received the common Ovsynch protocol (GPG: intramuscular, IM, injection of 50 mg gonadorelin, followed by an IM injection of 125 µg cloprostenol 7 days later, and a further IM injection of 50 mg gonadorelin 2 days later) or the Ovsynch protocol using nanofabricated hormones with the same dosages (NGPG) or half dosages (HNGPG) of each hormone. The ovarian structures and ovarian and luteal artery hemodynamic indices after each injection of the Ovsynch protocol using B-mode, color, and spectral Doppler scanning were monitored. Levels of blood serum progesterone (P4), estradiol (E2), and nitric oxide (NO) were determined. After the first gonadotrophin-releasing hormone (GnRH) injection, the number of large follicles decreased (p = 0.02) in NGPG and HNGPG, compared with GPG. HNGPG resulted in larger corpus luteum (CL) diameters (p = 0.001), and improved ovarian and luteal blood flow, compared with GPG and NGPG. Both NGPG and HNGPG significantly increased E2 and NO levels compared with GPG. HNGPG increased (p < 0.001) P4 levels compared with GPG, whereas NGPG resulted in an intermediate value. After prostaglandin F2α (PGF2α) injection, HNGPG had the largest diameter of CLs (p = 0.001) and significantly improved ovarian blood flow compared with GPG and NGPG. Both NGPG and HNGPG increased (p = 0.007) NO levels, compared with GPG. E2 level was increased (p = 0.028) in HNGPG, compared with GPG, whereas NGPG resulted in an intermediate value. During the follicular phase, HNGPG increased (p = 0.043) the number of medium follicles, shortened (p = 0.04) the interval to ovulation, and increased (p < 0.001) ovarian artery blood flow and levels (p < 0.001) of blood serum P4, E2, and NO, compared with GPG and NGPG. During the luteal phase, the numbers of CLs were similar among different experimental groups, whereas the diameter of CLs, luteal blood flow, and levels of blood serum P4 and NO increased (p < 0.001) in HNGPG, compared with GPG and NGPG. Conclusively, the nanodelivery system for the Ovsynch protocol could be recommended as a new strategy for improving estrous synchronization outcomes of goats while enabling lower hormone dose administration.

Perspective on the relationship between reproductive tract microbiota eubiosis and dysbiosis and reproductive function

The role played by microbiota is attracting growing attention within the scientific and medical community, in both human and animal fields, in the last years. Most of the studies have been focused on the intestinal microbiome, whilst little attention has been paid to other systems, like the reproductive tract of both females and males. However, there is a growing body of information showing the interplay between reproductive tract dysbiosis, due to the action of pathogens and/or unhealthy lifestyle, and reproductive disease and disorders in many mammalian species. The present review aims to summarise current knowledge on the biodiversity of the microbiota of the reproductive tract, and the possible relationships between eubiosis or dysbiosis and reproductive health and function in both females and males.

Improving Rabbit Doe Metabolism and Whole Reproductive Cycle Outcomes via Fatty Acid-Rich Moringa oleifera Leaf Extract Supplementation in Free and Nano-Encapsulated Forms

Simple Summary

Under intensive rabbit production systems, due to the increased energy requirements of reproductive events, specifically pregnancy and lactation, rabbit does may confront several metabolic disorders as a result of energy imbalance. Moringa oleifera leaf ethanolic extract (ME) is one of the phytogenic extracts that has an impressive range of phytochemicals, specifically fatty acids (FAs). These phytochemicals may be biologically effective to support metabolism and reproductive functions of rabbit does during different reproductive cycle events. However, the high FAs content of ME makes them highly susceptible to lipid oxidation, diminishing their nutritional value and biological effects. In this study, we aimed to test the effects of FAs of ME either in a free-from or in a nano-encapsulated form on metabolism, immunity, milk production, milk composition, and reproductive performance of rabbit does during different physiological status (premating, mating, pregnancy, and lactation). The results showed that ME improved health, metabolism, immune functions, milk production and composition, and reproductive performance of rabbit does. These effects remained obvious even when a lower dose of ME was used in a nano-encapsulated form.

Abstract

The effects of free and nano-encapsulated ME supplementations on the metabolism, immunity, milk production and composition, and reproductive performance of rabbit does during premating, mating, pregnancy, and lactation were investigated. Multiparous rabbit does (n = 26 per group) received 50 mg of free ME (FME) daily, 25 mg of nano-encapsulated ME (HNME), or 10 mg of nano-encapsulated ME (LNME) per kilogram of body weight or were not supplemented (C) during a whole reproductive cycle. The ME contained 30 fatty acids with 54.27% total unsaturated fatty acids (USFAs). The fatty acid encapsulation efficiency of alginate nanoparticles was 70.46%. Compared with the C group, rabbits in all ME treatments had significantly increased body weight, feed intake, and glucose concentration and significantly decreased non-esterified free fatty acids and β-hydroxybutyrate concentrations. Rabbits supplemented with ME also had significantly increased white blood cell counts, phagocytic activity, lysozyme activity, and immunoglobulin G and decreased interleukin-1β concentrations. Moreover, ME supplementation significantly increased the concentrations of colostrum immunoglobulins, milk yield and energy content, and milk USFAs (omega-3 and 6). Rabbit does in the ME treatments had significantly higher conception and parturition rates and better litter characteristics than the C rabbit does. These results demonstrate the positive role of ME fatty acids on the health status and productive and reproductive performance of rabbit does at different physiological stages. Compared with the FME treatment, these parameters were further improved in rabbits that received nano-encapsulated ME at lower doses, illustrating how nano-encapsulation technology improves the bioavailability of ME.

The Use of Probiotics for Management and Improvement of Reproductive Eubiosis and Function

Reproductive tract dysbiosis, due to the action of pathogens and/or unhealthy lifestyle, has been related to many reproductive diseases and disorders in mammalian species. Classically, such a problem has been confronted by the administration of antibiotics. Despite their effectiveness for controlling disease, treatments with antibiotics may negatively affect the fertility of males and females and, mainly, may induce antibiotic resistance. Accordingly, safer alternatives for maintaining reproductive system eubiosis, such as probiotics, are required. The present review summarizes the current knowledge on the biodiversity of the microbiota at the reproductive tract, possible changes in the case of dysbiosis, and their relationships with adequate reproductive health and functioning in both females and males. Afterwards, mechanisms of action and benefits of different probiotics are weighed since the biological activities of probiotics may provide a promising alternative to antibiotics for maintaining and restoring reproductive eubiosis and function. However, at present, it is still necessary for further research to focus on: (a) identifying mechanisms by which probiotics can affect reproductive processes; (b) the safety of probiotics to the host, specifically when consumed during sensitive reproductive windows such as pregnancy; and (c) the hazards instructions and regulatory rules required for marketing these biological-based therapies with sufficient safety. Thus, in this review, to draw a comprehensive overview with a relatively low number of clinical studies in this field, we showed the findings of studies performed either on human or animal models. This review strategy may help provide concrete facts on the eligible probiotic strains, probiotics colonization and transfer route, and prophylactic and/or therapeutic effects of different probiotic strains.

Mitigating the detrimental effects of heat stress in poultry through thermal conditioning and nutritional manipulation

The poultry industry faces several obstacles and challenges, including the changes in global temperature, increase in the per capita demand for meat and eggs, and the emergence and spread of various diseases. Among these, environmental challenges are one of the most severe hurdles impacting the growth and productivity of poultry. In particular, the increasing frequency and severity of heat waves over the past few years represent a major challenge, and this is expected to worsen in the coming decades. Chickens are highly susceptible to high ambient temperatures (thermal stress), which negatively affect their growth and productivity, leading to enormous economic losses. In the light of global warming, these losses are expected to increase in the near future. Specifically, the worsening of climate change and the rise in global temperatures have augmented the adverse effects of heat on poultry production worldwide. At present, the world population is approximately 7.9 billion, and it has been predicted to reach 9.3 billion by 2050 and approximately 11 billion by 2100, implying a great demand for protein supply; therefore, strategies to mitigate future poultry challenges must be urgently devised. To date, several mitigation measures have been adopted to minimize the negative effects of heat stress in poultry. Of these, thermal acclimation at the postnatal stage or throughout the embryonic stages has been explored as a promising approach; however, for large-scale application, this approach warrants further investigation to determine the suitable temperature and poultry age. Moreover, molecular mechanisms governing thermal conditioning are poorly understood. To this end, we sought to expand our knowledge of thermal conditioning in poultry, which may serve as a valuable reference to improve the thermotolerance of chickens via nutritional management and vitagene regulation. Vitagenes regulate the responses of poultry to diverse stresses. In recent years, nutritionists have paid close attention to bioactive compounds such as resveratrol, curcumin, and quercetin administered alone or in combination. These compounds activate vitagenes and other regulators of the antioxidant defense system, such as nuclear factor-erythroid 2-related factor 2. Overall, thermal conditioning may be an effective strategy to mitigate the negative effects of heat stress. In this context, the present review synthesizes information on the adverse impacts of thermal stress, elucidating the molecular mechanisms underlying thermal conditioning and its effects on the acquisition of tolerance to acute heat stress in later life. Finally, the role of some polyphenolic compounds, such as resveratrol, curcumin, and quercetin, in attenuating heat stress through the activation of the antioxidant defense system in poultry are discussed.

Effect of stocking density and vitamin E or zinc supplementation on growth, physiology, gene expression, and economic efficiency of growing broiler chicks

A total of 636 1-day-old male Cobb chicks were randomly assigned to seven treatments. The chicks were offered feed and water ad libitum throughout the experimental period. The first three groups included different stocking densities of broiler birds (low stocking density, LSD: 23 kg/m²; medium stocking density, MSD: 34 kg birds/m²; and high stocking density HSD: 39 kg birds/m²). The LSD group was considered a control group. The other four groups included MSD or HSD broiler birds supplemented with either Vit E (100 mg/kg DM diet; MSDVE and HSDVE) or Zn (100 mg/kg DM diet; MSDZn and HSDZn) in their basal diet. The main findings indicated that HSD and MSD negatively affected (p < 0.05) all variables under investigation compared with LSD. Compared with LSD, broiler birds in the MSD and HSD groups had lower body weights and higher feed conversion ratios, higher concentrations of blood plasma hormones (triiodothyronine thyroxine and corticosterone), and downregulated expression levels of hepatic growth hormone and insulin-like growth factor-l. In addition, broiler birds stocked at medium or high densities resulted in less economic return and profit. Vit E or Zn supplementation to broiler birds stocked at medium or high densities significantly reversed all adverse effects of HSD (> 23 kg/m²) on growth performance, hormones, and gene expression. It could be recommended that adding Zn at a level of 100 mg/kg per DM diet allows increasing the stocking density of broiler birds from 23 kg/m² to 34 birds/m² while maintaining the birds, welfare and economic profit.

The use of some plant-derived products as effective alternatives to antibiotic growth promoters in organic poultry production: a review

Improving poultry production, increasing poultry immunity, and reducing the disease spreading can be achieved by adding various potentially valuable ingredients to the feed or drinking water of poultry flocks. Because of the emergence of antimicrobial resistance, antibiotic growth promoters (AGP) in animal nutrition were prohibited. Additionally, consumer preferences tend towards purchasing products from livestock raised without antibiotics. Therefore, there is a critical need to find effective growth promoter alternatives and treatment methods for common poultry diseases. Some spice plants play important roles in improving the taste, aroma, and color of human food and their positive effects on human and animal health. The current review aimed to provide a broader perspective on some spice crops which can be effective alternatives to antibiotics in organic poultry production. These spices were including Thymus vulgaris, Cichorium intybus, Coriandrum sativum, Aloe vera, Heracleum persicum, Curcuma longa, and Glycyrrhiza glabra.

Effects of a Nanoencapsulated Moringa Leaf Ethanolic Extract on the Physiology, Metabolism and Reproductive Performance of Rabbit Does during Summer

This study investigated the effect of Moringa leaf ethanolic extract (MLEE) on heat-tolerance variables and the reproductive performance of rabbit does bred under hot climate conditions. Additionally, the effect of nanoencapsulation technology on the biological efficiency of MLEE was considered. A total of 56 rabbit does were randomly divided into four experimental groups and treated with 50 mg/kg body weight (BW) nonencapsulated MLEE, 25 or 10 mg/kg BW nanoencapsulated MLEE, or not treated (Control, C). The treatments continued for 50 days, including mating and pregnancy times. Physiological and hematochemical variables, hormonal profiles, and reproductive performance (kindling rate and litter characteristics) were determined. The active components of MLEE were identified. The results indicated that MLEE has 30 active components. All MLEE-based treatments reduced heat-stress-related indicators, such as rectal temperatures, respiratory rates and heart rate; improved hematochemical attributes, redox status, and hormones (progesterone and prolactin); and increased the total litter size, the kindling rate, litter size at birth and litter weight at birth. Adding MLEE can alleviate the negative impacts of heat stress by improving metabolism, redox status, and hormonal balance during pregnancy. These effects were seen whether MLLE was in free or encapsulated forms. However, the use of nanoencapsulated MLEE allowed 80% reduction (10 mg/kg BW) in the optimal dose (50 mg/kg BW) without affecting the efficiency of the treatment. These results support the importance of nanoencapsulation technology in improving the bioavailability of active components when they are orally administered.

Sustainable Management of Voluntary Culling Risk in Primiparous Zaraibi Goats in Egypt: Roles of Season and Reproductive and Milk Production-Related Traits

Simple Summary

Sustainable production of livestock farms mainly depends on efficient management and precise decisions. One of the most important managemental decisions that play a great role in the continuation of production and profitability is culling. Excluding non-efficient animals from the production cycle is a very critical decision as a wrong and aggressive culling decision may cause a certain loss in farm profitability by increasing costs of replacement. Identifying factors that affect culling risk can aid breeders in creating suitable interventions to maintain productive animals. In this study, logistic regression analysis was used to study the pattern of culling risk factors in primiparous Nubian goats. The effect of ten independent factors including season, reproductive traits, and milk production traits on the percentage of voluntary culling risk was studied. The presented outcomes clearly indicated that birth weight, total litter size at birth, litter size at weaning, number of kids dead, total milk yield, average daily milk yield, lactation period, and age at first kidding had significant effects on culling risk, while both the birth season of the dam and kidding season did not exhibit significant effects on culling risk. In practice, monitoring of traits that indicate milk imbalance and older age at first kidding could promote identifying goats at high risk of being culled.

Abstract

The purpose of the current study is to reconnoiter the relationships between season (birth season, BS, and kidding season, KS), reproductive traits (birth weight, BW; total litter size at birth, TLS; litter size at weaning, LSW; the number of kids dead, NKD, and; age at first kidding, AFK) and milk production (total milk yield, TMY; average daily milk yield, DMY, and; lactation period, LP), with voluntary culling risk in primiparous Zaraibi goats. Records of 637 primiparous does were collected during the period 2008–2014 from a herd of Zaraibi goats raised at the El-Serw Experimental Station, which belongs to the Animal Production Research Institute. Our data revealed that the voluntary and involuntary culling was 89.12% and 10.88%, respectively. Moreover, the BW, TLS, LSW, NKD, TMY, DMY, LP, AFK had significant effects on culling risk (p < 0.05), while both the season of birth and kidding did not exhibit significant effects on culling risk. The thinnest goats at birth were more likely to be culled compared to those with body energy reserves. Does with weaned twins and triplets kids were 9.5% (OR = 0.905) and 43% (OR = 0.570), respectively less likely to be culled compared to those with singles. Likewise, does with dead twins and triplets kids had 2.566 and 2.138 times, respectively higher odds of culling compared to those with singles. Interestingly, culling risk decreased with 74.6% (OR = 0.254), 79.8% (OR = 0.202), and 75.6% (OR = 0.244) in does with TMY, LP, and DMY more than 230 kg, 260 days, and 0.800 kg, respectively compared to their counterparts (less than 185 kg, 240 day, and 0.500 kg, respectively). Moreover, culling risk increased steadily along with increasing AFK; the animals with an AFK of more than 24 months had 2.974 times higher odds of culling compared to those with an AFK that varied between 22 and 24 months. It could be concluded that the most critical issues for higher culling probability in dairy goats were attributed to the lower TMY (<185 kg) and DMY (<0.5 kg), and shorter LP (<245 days), as well as older age at first kidding (>2 years). This putative information could be used as indicators to enhance the management and genetic approaches in dairy goats and thus sustain productivity with low cost.

Nanotechnology and Reproductive Management of Farm Animals: Challenges and Advances

Reproductive efficiency of farm animals has central consequences on productivity and profitability of livestock farming systems. Optimal reproductive management is based on applying different strategies, including biological, hormonal, nutritional strategies, as well as reproductive disease control. These strategies should not only guarantee sufficient reproductive outcomes but should also comply with practical and ethical aspects. For example, the efficiency of the biological- and hormonal-based reproductive strategies is mainly related to several biological factors and physiological status of animals, and of nutritional strategies, additional factors, such as digestion and absorption, can contribute. In addition, the management of reproductive-related diseases is challenged by the concerns regarding the intensive use of antibiotics and the development of antimicrobial resistant strains. The emergence of nanotechnology applications in livestock farming systems may present innovative and new solutions for overcoming reproductive management challenges. Many drugs (hormones and antibiotics), biological molecules, and nutrients can acquire novel physicochemical properties using nanotechnology; the main ones are improved bioavailability, higher cellular uptake, controlled sustained release, and lower toxicity compared with ordinary forms. In this review, we illustrate advances in the most common reproductive management strategies by applying nanotechnology, considering the current challenges of each strategy.

Nanominerals: Fabrication Methods, Benefits and Hazards, and Their Applications in Ruminants with Special Reference to Selenium and Zinc Nanoparticles

Simple Summary

Nanomaterials can contribute to the sustainability of the livestock sector through improving the quantitative and qualitative production of safe, healthy, and functional animal products. Given the diverse nanotechnology applications in the animal nutrition field, the administration of nanominerals can substantially enhance the bioavailability of respective minerals by increasing cellular uptake and avoiding mineral antagonism. Nanominerals are also helpful for improving reproductive performance and assisted reproductive technologies outcomes of animals. Despite the promising positive effects of nanominerals on animal performance (growth, feed utilization, nutrient bioavailability, antioxidant status, and immune response), there are various challenges related to nanominerals, including their metabolism and fate in the animal’s body. Thus, the economic, legal, and ethical implications of nanomaterials must also be considered by the authority.

Abstract

Nanotechnology is one of the major advanced technologies applied in different fields, including agriculture, livestock, medicine, and food sectors. Nanomaterials can help maintain the sustainability of the livestock sector through improving quantitative and qualitative production of safe, healthy, and functional animal products. Given the diverse nanotechnology applications in the animal nutrition field, the use of nanomaterials opens the horizon of opportunities for enhancing feed utilization and efficiency in animal production. Nanotechnology facilitates the development of nano vehicles for nutrients (including trace minerals), allowing efficient delivery to improve digestion and absorption for better nutrient metabolism and physiology. Nanominerals are interesting alternatives for inorganic and organic minerals for animals that can substantially enhance the bioavailability and reduce pollution. Nanominerals promote antioxidant activity, and improve growth performance, reproductive performance, immune response, intestinal health, and the nutritional value of animal products. Nanominerals are also helpful for improving assisted reproductive technologies (ART) outcomes by enriching media for cryopreservation of spermatozoa, oocytes, and embryos with antioxidant nanominerals. Despite the promising positive effects of nanominerals on animal performance and health, there are various challenges related to nanominerals, including their metabolism and fate in the animal’s body. Thus, the economic, legal, and ethical implications of nanomaterials must also be considered by the authority. This review highlights the benefits of including nanominerals (particularly nano-selenium and nano-zinc) in animal diets and/or cryopreservation media, focusing on modes of action, physiological effects, and the potential toxicity of their impact on human health.

Impact of specific essential oils blend on milk production, serum biochemical parameters and kid performance of goats

Effects of cinnamon, thyme, and peppermint essential oils blend (EOB) on milk production, serum constituents, and energy balance of early lactating does and performance of their kids were investigated. Twenty-seven late pregnant Damascus goats were grouped into two treatments: EOB (n = 14) received orally 1.5 ml EOB/d and control (n = 13) received orally 1.5 ml water/d. The trail started 15 days before the expected kidding date and lasted for 30 days postpartum while sample collection continued until the eighth week of lactation. Milk yield and composition, maternal metabolic profile, immunoglobulin (IgG), and weights of kids were monitored throughout 8 consecutive weeks postpartum. Energy corrected milk (ECM), milk energy value (MEV), net energy for lactation (NEL), and energy balance were estimated. Does treated with EOB had higher (p < 0.05) milk yield, ECM, and NEL than control. Treated does had higher (p = 0.02) energy balance than control does. The EOB increased (p < 0.05) concentrations of serum albumin, cholesterol, triglycerides, and IgG. Treatment with EOB improved (p < 0.05) weaning weight and total weight gain of single kids. Administration of EOB for 45 days during the transition period could improve milk production, metabolic status and energy balance of goats and performance of kids.

Potential impacts of COVID-19 on reproductive health: Scientific findings and social dimension

COVID-19 virus is classified as a respiratory disease that can be mainly transmitted via respiratory droplets, however, there are recently published reports suggested its ability to transmit via sexual intercourse, assisted reproductive technology (ART) treatments, pregnancy, and nursing. Although SARS-CoV-2 mainly attacks respiratory systems, manifestations of multiple organs have been detected. A significant concern was raised about whether COVID-19 may affect female and male reproductive functions. These findings imposed more restrictions on social relationships between individuals even if inside the family, adding more physiologic load. In this context, there is a crucial need to identify the biological and behavioral reproductive risk factors associated with COVID-19 disease. Questions regarding the potential risks of sexual transmission during intercourse and/or application of ART, vertical transmission (throughout pregnancy, delivery, and breastfeeding), the health of pregnant and postpartum women, and fetal or postnatal health problems of neonates/children remain largely unanswered. The contribution of individuals to different social and economic activities depends on the maintenance of good quality life and health. The ongoing COVID-19 pandemic raised on the end of December 2019 has drastically affected different aspects of human wellbeing. The pandemic not only affected the health of individuals, but also negatively affected mental health and social interaction. This review illustrates: a) scientific findings related to the impact of the COVID-19 pandemic on the reproductive process, considering gender, hormonal balance, gonad functions, pregnancy, and ART, b) the sociosexual dimension of COVID-19 disease and precautions that should be taken to avoid infection via sexual transmission or vertical transmission, which may alleviate the fear associated with continuing normal social relationships and economic activities.

Improving Reproductive Performance and Health of Mammals Using Honeybee Products

Honeybee products have positive effects on the reproductive performance of mammals. Many honeybee product constituents are biologically active, with antioxidant, antimicrobial, antiviral, anti-inflammatory, immunomodulatory, antifungal, wound-healing, and cardio-protective properties. Honeybee products also improve male and female fertility rates by enhancing gamete cryopreservation, in vitro maturation and fertilization, and embryo development. Previously published studies confirmed their efficacy for alleviating reproductive toxicity caused by contaminants and lifestyle habits that impair overall health and well-being. However, high-dose oral administration of honeybee products may adversely affect the reproductive system, and unfavorable effects were alleviated by treatment cessation. For this reason, this review proposes that bioactive components from bee products can be used as a strategy for improving the reproductive performance and health of mammals.

Efficiency of GnRH-Loaded Chitosan Nanoparticles for Inducing LH Secretion and Fertile Ovulations in Protocols for Artificial Insemination in Rabbit Does

Simple Summary

Nano-drug delivery systems can be employed for improving ovulation induction prior to artificial insemination (AI) in rabbits. In this study, different routes of administration and different doses of GnRH–loaded chitosan nanoparticles (GnRH–ChNPs) were assessed for inducing ovulation in rabbits, proving their usefulness to reduce the GnRH dose and animal handling and improving AI outcomes. The use of GnRH–ChNPs allows for the reduction of the conventional intramuscular GnRH dose to half without compromising fertility. However, the addition of GnRH–ChNPs to semen extenders, although successfully inducing ovulation, has negative impacts on fertility. Thus, more studies are needed to allow further adjustments.

Abstract

Gonadotropin-releasing hormone (GnRH)–loaded chitosan nanoparticles (GnRH–ChNPs) were used at different doses and routes of administration to induce ovulation in rabbits as an attempt to improve artificial insemination (AI) procedures and outcomes. In this study, the characteristics (size, polydispersity, loading efficiency, and zeta-potential) of GnRH–ChNPs and the GnRH release pattern were determined in an in vitro study. A first in vivo study assessed the pituitary and ovarian response to different GnRH–ChNPs doses and routes of administration (two i.m. doses, Group HM = 0.4 µg and Group QM = 0.2 µg, and two intravaginal doses, Group HV = 4 µg and Group QV = 2 µg) against a control group (C) receiving bare GnRH (0.8 µg). The HM, QM, and HV treatments induced an earlier LH-surge (90 min) than that observed in group C (120 min), whilst the QV treatment failed to induce such LH surge. The number of ovulation points was similar among treatments, except for the QV treatment (no ovulation points). A second in vivo study was consequently developed to determine the hormonal (progesterone, P₄, and estradiol, E₂) profile and pregnancy outcomes of both HM and HV treatments against group C. The treatment HM, but not the treatment HV, showed adequate P₄ and E₂ concentrations, conception and parturition rates, litter size, litter weight, and viability rate at birth. Overall, the use of GnRH–ChNPs allows for a reduction in the conventional intramuscular GnRH dose to half without compromising fertility. However, the addition of GnRH–ChNPs to semen extenders, although successfully inducing ovulation, has negative impacts on fertility. Thus, more studies are needed to explore this point and allow further adjustments.

Polyphenols in Farm Animals: Source of Reproductive Gain or Waste?

Reproduction is a complex process that is substantially affected by environmental cues, specifically feed/diet and its components. Farm animals as herbivorous animals are exposed to a large amount of polyphenols present in their natural feeding system, in alternative feed resources (shrubs, trees, and agro-industrial byproducts), and in polyphenol-enriched additives. Such exposure has increased because of the well-known antioxidant properties of polyphenols. However, to date, the argumentation around the impacts of polyphenols on reproductive events is debatable. Accordingly, the intensive inclusion of polyphenols in the diets of breeding animals and in media for assisted reproductive techniques needs further investigation, avoiding any source of reproductive waste and achieving maximum benefits. This review illustrates recent findings connecting dietary polyphenols consumption from different sources (conventional and unconventional feeds) with the reproductive performance of farm animals, underpinned by the findings of in vitro studies in this field. This update will help in formulating proper diets, optimizing the introduction of new plant species, and feed additives for improving reproductive function, avoiding possible reproductive wastes and maximizing possible benefits.

Animal Welfare and Livestock Supply Chain Sustainability Under the COVID-19 Outbreak: An Overview

The COVID-19 pandemic, caused by the emergence of a new strain of coronavirus (SARS-CoV-2) around the end of December 2019, has caused a worldwide public health emergency and a socioeconomic crisis during 2020. The lockdown imposed to cope with the health issues caused by the outbreak of the disease has dramatically challenged and negatively affected all the economic sectors of the modern global economy. Specifically, the livestock sector and its related industries are among the most impacted sectors. This is mainly ascribed to the limitations of animal movement and the decrease of production inputs' availability. Other factors negatively affecting the sustainability of the livestock sector have been the shortage of workers due to the lockdown/curfew, the strong decrease in the purchasing power of the consumer, and the intensification of health care tasks. Such an impact is not only highly relevant because of their economic consequences, but also because of the effects of the lockdown and sanitary rules on animal care and welfare. The current review aims to offer: (a) a comprehensive overview of the impact of COVID-19 on the welfare of farm animals and on the performance of livestock farming systems, on food chain sustainability, and finally, on the global economy and food security; and (b) a prospective outline of alleviation actions.

Housing Management of Male Dromedaries during the Rut Season: Effects of Social Contact between Males and Movement Control on Sexual Behavior, Blood Metabolites and Hormonal Balance

Simple Summary

The effect of different housing management systems on the behavior, metabolites and hormonal balance in male dromedaries during the rutting season was evaluated. Male dromedaries that were housed in groups and allowed to walk around had significantly higher frequencies of ruminating, standing, walking and sexual-related behaviors than those housed individually or tied. Movement control had significant effects on blood serum metabolites and hormone concentrations. Fenced and exercised male dromedaries had higher (p < 0.05) concentrations of blood serum transaminases, free radicals, glucose, cholesterol and testosterone and lower (p < 0.05) concentrations of cortisol and triiodothyronine (T3) than tied male dromedaries. Animal social interaction is of particular importance for maintaining physical; psychological and sexual behaviors. Allowing walking-around exercise for captive animals improves their metabolic status and decreases captive stress effects. Housing systems that guarantee social interaction and physical activity are being the most suitable housing management systems for male dromedaries during the rutting season.

Abstract

The current study aimed to evaluate the effect of different housing management systems on behavior, blood metabolites and hormonal balance in male dromedaries during the rutting season. Forty-eight adult male dromedaries were stratified in a two by three factorial experiment design, testing effects of social contact (single and group) and movement control (tied, fenced and exercise). During a ten-week experimental period, male dromedaries were filmed weekly for 20 min three times per day to evaluate their behaviors. Blood samples were collected and analyzed for serum metabolites and hormones. Both animal social contact and movement control significantly affected maintenance, posture and sexual behaviors. Male dromedaries housed in groups expressed higher frequencies of sexual desire-related behaviors (teeth grinding, open legs, tail flapping, dulla “soft palate exteriorization”, blathering and urination) than those individually housed. Animal movement control significantly affected sexual behavior; fenced and exercised male dromedaries expressed higher frequencies of sexual desire-related behaviors than tied ones. Male dromedaries housed in groups and allowed to walk around had significantly higher frequencies of ruminating, standing, walking and sexual-related behaviors than those housed individually or tied. Movement control had significant effects on blood serum metabolites and hormone concentrations. Fenced and exercised male dromedaries had higher (p < 0.05) concentrations of blood serum transaminases, free radicals, glucose, cholesterol and testosterone (2.91 and 2.09 ng/mL, respectively) and lower (p < 0.05) concentrations of cortisol (44.12 and 53.52 nmol/L, respectively) and triiodothyronine (1.68 and 1.91 ng/mL, respectively) than tied male dromedaries. In conclusion, animal social interaction is of particular importance for maintaining physical, psychological and sexual behaviors. Allowing walking-around exercise for captive animals improves their metabolic status and decreases captive stress effects. Housing systems that guarantee social interaction and physical activity are the most suitable housing management systems for captive male dromedaries during the rutting season.

Effects of Organic Selenium on the Physiological Response, Blood Metabolites, Redox Status, Semen Quality, and Fertility of Rabbit Bucks Kept Under Natural Heat Stress Conditions

Heat stress can impair the general health of rabbit bucks by disturbing physiological homeostasis with negative consequences in animal welfare and remarkable decline in reproductive performance. Selenium (Se) can control a number of vital biological processes. Thus, the effects of organic selenium (OSe) supplementation on the blood metabolites, redox status, semen quality, testicular histology, seminal plasma protein profile, and fertility of rabbit bucks kept under natural heat stress conditions were studied. Adult V-line male rabbits were fed a basal diet supplemented with 0.3 mg OSe/kg dry matter (DM) diet (OSe, n = 9) or not (control, CON, n = 9) for 12 weeks. The results showed that rabbits fed the OSe diet had 73.68 and 68.75% higher (P < 0.05) OSe concentrations in the blood serum and seminal plasma, respectively, than rabbits fed the CON diet. The OSe diet significantly decreased the rectal temperature and respiration rate and significantly increased the blood serum concentrations of total protein, albumin, glucose, and glutathione peroxidase compared to the CON diet. Rabbits fed the OSe diet had lower reaction times (12.53 vs. 5.84 s, ± 0.79, P < 0.01) and higher total functional sperm counts (116.74 vs. 335.23 × 10⁶/ml, ± 24.68, P < 0.001) and percentages of integrated sperm membranes (60.38 vs. 79.19%, ± 1.69, P < 0.01) than rabbits fed the CON diet. Rabbits fed the OSe diet had higher (P < 0.01) contents of seminal plasma total protein, albumin, alanine transaminase, fructose, and total antioxidant capacity and lower (P < 0.001) malondialdehyde (MDA) levels than those fed the CON diet. Rabbits fed the OSe diet had sperm cells with higher levels of integrated DNA than those fed the CON diet. The seminal plasma of rabbits fed the OSe diet contained four new proteins, with molecular weights of 19.0, 21.5, 30.0, and 44.0 kDa. The kindling rates, litter size, and weight at birth of females mated with males fed the OSe diet were significantly higher than those of females mated with males fed the CON diet. In summary, the inclusion of 0.3 mg OSe/kg DM diet of naturally heat-stressed rabbit bucks countered the negative impacts of elevated environmental temperature on physiological homeostasis, semen quality, and fertility.

Reproductive performance of goats treated with free gonadorelin or nanoconjugated gonadorelin at estrus

The reproductive performance of goats that received a GnRH analog (gonadorelin) fabricated with or without chitosan-sodium tripolyphosphate (TPP) nanoparticles on the day of estrus (day 0) was evaluated. The chitosan-TPP polymer was conjugated with gonadorelin using an ionic gelation method. Thirty-three multiparous Zaraiebi goats were synchronized for estrus with 2 intramuscular (im) injections of 125 μg prostaglandin F_2α 14 d apart. Goats showing signs of estrus were divided equally into 3 experimental groups and received a single im injection of 1 mL physiological saline (placebo; control), 50 μg/mL gonadorelin (GnRH), or 12.5 μg (quarter of GnRH dose)/mL chitosan-TPP-conjugated gonadorelin nanoparticles (NGnRH). Each goat underwent ultrasound imaging of their ovaries at day 0 and at day 10 after mating, and pregnancy was diagnosed 28 and 45 d after mating. The concentrations of estradiol (E₂) and progesterone (P₄) were determined at day 0 and at days 7, 14, 21, and 42 after mating. NGnRH size, polydispersity, and zeta potential were 93.91 nm, 0.302, and 11.6 mV, respectively. Chitosan-TPP nanoparticles showed 91.2% entrapment efficiency for GnRH. No differences in estrus rate, interval to estrus, or ovarian structure at day 0 were observed among the experimental groups, but the GnRH and NGnRH treatments significantly decreased the duration of estrus compared with the control. At day 10 after mating, both GnRH and NGnRH increased (P = 0.011) the number of corpora lutea compared with the control. Treatment with GnRH increased (P = 0.023) serum E₂ concentrations from day 7 to 42 after mating compared with NGnRH and control treatments. The highest (P = 0.043) serum P₄ concentration was observed in the GnRH group, followed by the NGnRH and control groups. The increase in serum P₄ concentration started earlier a on day 7 in the GnRH group but later on day 14 in the NGnRH group. Compared with the control, GnRH resulted in a higher (P = 0.041) P₄-to-E₂ ratio, followed by NGnRH. Both gonadorelin treatments significantly increased the twinning rate, the number of embryos at days 28 and 42, and prolificacy and decreased pregnancy losses compared with the control. In conclusion, the administration of GnRH at the time of estrus improved the prolificacy of goats by increasing both the ovulation rate and the number of embryos. In addition, the nanoformulation developed in this study allowed a 75% reduction in the conventional dose of gonadorelin without affecting the fertility and prolificacy of goats, indicating the bioavailability of the reduced GnRH dose after conjugation with developed nanoformula.

Soybean isoflavone affects in rabbits: Effects on metabolism, antioxidant capacity, hormonal balance and reproductive performance

Though soybean isoflavones (SBI) have pharmaceutical properties, the compounds also have endocrine disrupting activities that may adversely affect fertility of mammals. The effects of SBI on metabolism, antioxidant capacity, hormonal balance and reproductive performance of male rabbits were investigated. Adult male rabbits (n = 21) fed an isoflavone-free diet were orally treated with 0 (control; CON), 5 (small; LSBI) or 20 (large; HSBI) mg of SBI/kg body weight/day for 12 weeks. Both SBI doses resulted in lesser blood plasma total protein concentrations, while there were no effects on glucose and cholesterol concentrations compared to CON. The HSBI-treated males had the greatest (P <  0.05) blood plasma total antioxidant capacity and least malondialdehyde. Treatment with both SBI doses induced a 43% increase in triiodothyronine concentrations (P < 0.05) and 82% in reaction times (P <  0.001), while decreased sperm concentrations (P =  0.01) and blood plasma testosterone concentrations (P =  0.017) 26% and 19%, respectively. The total functional sperm fraction was less (P <  0.05) in the HSBI group; however, there was no effect of the LSBI treatment as compared to values for the CON group. The kindling rates of females mated to HSBI-treated males tended to be less (P =  0.081) than those of does mated with LSBI or CON males. In conclusion, only the HSBI treatment improved antioxidant status; whereas, treatment with both LSBI and HSBI doses induced a hormonal imbalance which led to an impaired testis function indicating the sensitivity of the adult male reproductive system to SBI actions.

Prolonged exposure of dietary phytoestrogens on semen characteristics and reproductive performance of rabbit bucks

The effects of inclusion of different sources of dietary phytoestrogens on antioxidant capacity, hormonal balance, libido, semen quality, and fertility of rabbit bucks were studied. Twenty-one, adult, fertile, V-line bucks were randomly allocated into 3 homogenous groups (n = 7/treatment) and received control diet (phytoestrogens-free diet, CON) or soybean meal isoflavones-containing diet (SMI) or linseed meal lignans-containing diet (LML) for 12 wk. The diets were formulated to be isocaloric and isonitrogenous. The concentrations of isoflavones in the SMI diet were 24.04 mg/100 g dry matter (DM) daidzein and 13.10 mg/100 g DM genistein. The major phytoestrogen detected in the LML diet was secoisolariciresinol (36.80 mg/100 g DM). Treatment had no effects on body weight, feed intake and rectal temperature of bucks. Compared with control, bucks fed the SMI and LML diets had higher (P < 0.001) blood plasma total antioxidant capacity (0.98 ± 0.12, 1.50 ± 0.13, and 2.29 ± 0.17 mM/L for CON, SMI, and LML, respectively), and lower (P < 0.01) blood plasma malondialdehyde (2.76 ± 0.23, 1.76 ± 0.16, and 1.70 ± 0.18 nmol/mL for CON, SMI, and LML, respectively), whereas activities of reduced glutathione and superoxide dismutase (SOD) enzymes were not affected. Bucks fed the SMI and LML diets had greater (P < 0.001) concentrations of blood plasma triiodothyronine. Feeding the SMI and LML diets decreased (P < 0.01) libido (8.26 ± 0.71, 12.18 ± 0.97, and 14.12 ± 1.12 s for CON, SMI, and LML, respectively), sperm concentration (327.7 ± 21.6, 265.8 ± 36.8, and 226.5 ± 20.1 × 106/mL for CON, SMI, and LML, respectively), testosterone (5.16 ± 0.95, 3.91 ± 0.63, and 3.04 ± 0.92 ng/mL for CON, SMI, and LML, respectively), and seminal plasma fructose compared with the CON diet. The percentage of progressive motile sperm was improved (P < 0.001) by both phytoestrogen-containing diets. Feeding the SMI diet increased (P = 0.02) the percentage of live sperm compared with CON, whereas LML resulted in an intermediate value. Dietary treatment of bucks did not affect kindling rates or litter sizes of does, and did not affect birth weights or viabilities of kits. In conclusion, prolonged consumption of dietary isoflavones or lignans did not impair semen fertilizability. This may be due to the benefits of antioxidant activity or due to the benefits of other components in the diet. Dietary phytoestrogens did evoke obvious decreases in libido and steroidogenesis with altered semen parameters.

Effects of Trifolium alexandrinum phytoestrogens on oestrous behaviour, ovarian activity and reproductive performance of ewes during the non-breeding season

Phytoestrogens are classified as naturally occurring endocrine disrupting chemicals that may affect reproductive performance of farm animals. To investigate the effects of Berseem clover phytoestrogens on reproductive performance of seasonal anoestrus ewes, twenty four late pregnant Rahmani ewes were fed either Berseem clover or maize silage (n = 12/treatment). Treatment started 2 months prepartum and continued until oestrous induction (week 8 postpartum), using the CIDR-eCG based protocol, and early pregnancy. Throughout the 2-8 weeks postpartum, oestrous rate and ovarian activity were not affected by treatment. After oestrous induction, ewes in both groups expressed comparable oestrous rates; however feeding Berseem clover extended (P < 0.05) interval to oestrus (57.00 compared with 42.54 h) and shortened (P < 0.05) oestrous duration (20.0 compared with 34.90 h). Feeding Berseem clover did not affect follicular activity except the number of medium follicles, which was less (P < 0.05) on day of oestrus (Day 0). Feeding maize silage increased (P < 0.05) the total number of follicles and number of small and medium follicles the day before oestrus (Day -1). On Day 0, the greater total number of follicles was due to the greater (P < 0.05) number of medium follicles that was associated with less number of small follicles. Although, the number and diameter of corpora lutea (CLs) were not affected by treatment, serum P₄ concentration was greater (P < 0.05) for ewes fed maize silage than for those fed Berseem clover. Fecundity and litter size tended to be greater (about 35%; P = 0.132 and 0.085, respectively) in the maize silage fed ewes. In conclusion, feeding Berseem clover throughout seasonal anoestrus disrupted aspects of behavioural oestrus and there was less luteal P₄ synthesis and fecundity of ewes.

Effects of a single administration of different gonadotropins on day 7 post-insemination on pregnancy outcomes of rabbit does

This study aimed to investigate the effects of a single administration of one of three different gonadotropins on Day 7 post-insemination on ovarian activity, progesterone (P₄) concentration and pregnancy outcomes of rabbit does. Multiparous, non-lactating, V-line does were artificially inseminated after synchronization and ovulation induction with equine chorionic gonadotropin (eCG; 25 IU im) and gonadotropin releasing hormone (GnRH; 0.8  μg buserelin im) 48 h later. On Day 7 post-inseminarion, does were randomly allocated into four groups (n = 40/group). Does of each group were intramuscularly injected with a single dose of one of physiological saline (placebo; control), GnRH (0.8  μg buserelin), human chorionic gonadotropin (hCG; 25 IU) or eCG (25 IU). Concentration of serum P₄ was determined on Days 6, 9, 11 and 18 post-insemination. On Day 14 post-insemination, the ovaries and reproductive tracts of pregnant does were removed and weighed. Also, numbers of visible follicles, hemorrhagic follicles, corpora lutea of pregnancy (pCLs), new CLs (nCLs; formed after Day 7 post-insemination) and implantation sites were recorded. Conception rate, parturition rate, abortion rate, litter size/weight and litter viability were recorded. The highest (P < 0.05) reproductive tract and ovary weights were for eCG. The highest (P < 0.05) number of visible ovarian follicles was for eCG, whereas the lowest (P < 0.05) was for GnRH. Treatment with eCG increased (P < 0.05) numbers of pCLs and total implantation sites compared to the other groups. Treatment with GnRH or hCG increased (P < 0.05) number of nCLs compared to control and eCG. The highest rate of fetal loss was in does treated with GnRH. The concentration of serum P₄ decreased (P < 0.05) following the treatment with GnRH and continued low until Day 18. However, it remained in line for control, hCG and eCG groups up to Day 11, then decreased (P < 0.05) for control and hCG on Day 18, being lower for hCG than control, while continued to increase for eCG up to Day 18. Compared to control, treatment with eCG improved (P < 0.05) conception and parturition rates by 24 and 22%; respectively, while GnRH and hCG treatments decreased (P < 0.05) them by 57 and 47.6%; respectively. Litter size and litter weight at birth were improved by eCG, but were adversely affectd by GnRH and hCG. In conclusion, a single administration of eCG 7 Days post-insemination could be recommended for improving pregnancy outcomes in rabbits.

Genetic screening of FecB, FecXG and FecXI mutations and their linkage with litter size in Barki and Rahmani sheep breeds

Characterization of fecundity genes offers the opportunity to improve production efficiency, and the consequent increase in litter size in livestock industry, through utilizing them in breeding programs. The main objective of this study was to detect the BMPR-IB, BMP15 and GDF9 gene mutations and to investigate whether these mutations are associated with litter size in Egyptian sheep breeds. To achieve this goal, 73 adult ewes representing Barki (n = 33) and Rahmani (n = 40) breeds were used. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) screening approach was used to detect the presence of FecB, FecX^G and FecX^I mutations in the two selected breeds. Results of this study showed that the three different candidate gene mutations, namely FecB, FecX^G and FecX^I are not present among these selected populations of the Egyptian breeds. Further studies regarding other mutations and/or other genes, which may influence ovulation rate, should be carried out to determine the type and mode of inheritance of such genes in Egyptian sheep breeds.

Metabolic Attributes, Milk Production and Ovarian Activity of Ewes Supplemented with a Soluble Sugar or a Protected-Fat as Different Energy Sources During Postpartum Period

The effects of two dietary supplemental energy sources on metabolic attributes, milk production and ovarian activity of ewes during early to mid-postpartum period were studied using thirty multiparous lactating ewes (Rahmani × Barki) weighing 43.10±1.22 kg and 3-6 years old. The ewes were assigned to three groups (n=10 per group). All ewes received the same diet supplemented with isocaloric and isonitrogenous protected-palm oil (50 g/ewe/d, F-group) or a sugar cane molasses (140 g/ewe/d, M-group) or without supplementation (control, C-group), for 60 days starting 2 weeks postpartum. Results showed that, during the experimental period, both energy sources reduced (P<0.05) body weight loss of ewes compared with the control (2.57 kg in F-group, 0.911 kg in M-group and 4.71 kg in C-group). The metabolic profiles of ewes were affected by the sources of energy, the highest (P<0.05) concentration of serum triglycerides was in the F-group, whereas the highest (P<0.05) concentration of serum insulin was in the M-group. The lowest serum glucose concentration was (P<0.05) in the F-group (73.20 mg/dL) and the highest in the C-group (76.85 mg/dL), whereas it was intermediate in the M-group (74.69 mg/dL). Ewes in the F-group had (P<0.05) the highest milk yield and energy-corrected milk (531.72 g/d and 554.40 g/d, respectively) compared with those in the M-group (491.76 g/d and 525.12 g/d, respectively) and C-group (429.96 g/d and 462.00 g/d, respectively). The highest (P<0.05) number of corpora lutea (CL; ovulation activity) was in the F-group (0.45), whereas it was not different between the M-group (0.25) and the C-group (0.15). In conclusion, during early to mid-postpartum period, protected-fat supplementation increased serum triglycerides concentration which was effectively used as an energyyielding nutrient for improving milk production. It could also be suggested that specific fatty acid in protected-fat improved quality of the ovulatory follicle and thus occurrence of ovulation.

Evaluation of the Effects of Cypermethrin on Female Reproductive Function by Using Rabbit Model and of the Protective Role of Chinese Propolis

The prophylactic effects of Chinese propolis against cypermethrin toxicity were evaluated by performing ovary and uterus histopathology, as well as by characterizing ovarian function, embryos, and litters. Cypermethrin induced atypia in the ovary and uterus, and decreased the ovulation sites and the number of embryos. Cypermethrin-induced oxidative stress during pregnancy, decreased the parturition rate as well as the number and weight of offspring and increased the incidence of morphological malformations in the offspring. Administration of propolis to cypermethrin-treated animals mitigated cypermethrin-induced reproductive toxicity.

Effect of GnRH treatment on ovarian activity and reproductive performance of low-prolific Rahmani ewes

This study was designed to evaluate the effect of GnRH treatment during different times of the reproductive cycle on ovarian activity, progesterone (P4) concentration, and subsequent fertility of low-prolific, subtropical, Rahmani ewes during breeding season. Forty-five ewes were synchronized for estrus using a double injection of 0.5 mL of PGF2α agonist (125-μg cloprostenol), 11 days apart. Ewes showing estrus (Day 0) were treated with 1 mL of GnRH agonist (4-μg buserelin) on the day of estrus (GnRH0, n = 12) or 7 days post-mating (GnRH7, n = 10) or on both days (GnRH0+7, n = 11) or not (control, n = 12). Ovarian response to the treatment and diagnosis of pregnancy were ultrasonographically monitored. Also, serum P4 concentration was determined weekly throughout 28 days post-mating. Results showed that neither total number of follicles nor their populations were changed on Day 0 or 7 days post-mating by the GnRH treatment. GnRH treatment on Day 0 or Day 7 post-mating or both days did not enhance ovulation rate compared with the control. The mean numbers of accessory CL increased (P < 0.05) in the GnRH7 group than those in the control and GnRH0 groups, whereas it was intermediate in the GnRH0+7 group. The greatest (P < 0.05) overall mean of serum P4 concentration was for the GnRH7 and GnRH0+7 groups, followed by the GnRH0 and control groups. Serum P4 concentration increased (P < 0.05) on Day 14 post-mating and continued higher (P < 0.05) until Day 28 post-mating in the GnRH7 and GnRH0+7 groups compared with the control. Regardless of the time of GnRH administration, GnRH treatment reduced (P < 0.05) pregnancy loss from Day 40 post-mating to parturition and tended to enhance (P < 0.20) lambing rate compared with the control. In conclusion, a single dose of GnRH at the time of estrus or 7 days post-mating could be used as an effective protocol to decrease pregnancy loss from Day 40 after mating to parturition in low-prolific Rahmani ewes.

Effect of short-term supplementation with rumen-protected fat during the late luteal phase on reproduction and metabolism of ewes

This study was designed to study the effect of short-term supplementation with rumen-protected fat during the late luteal phase on reproduction and metabolism of sheep during breeding season. Seventy-six ewes (Rahmani, Barki and Awassi × Barki) were allocated to two groups considering genotype: the control ewes (C-group) received a maintenance diet, and the fat-supplemented ewes (F-group) received the maintenance diet plus 50 g/head/day of rumen- protected fat (Megalac) for 9 days during which oestrus was synchronized. The latter had been accomplished using double intramuscular injection of prostaglandin F2α (PGF2α ) 11 days apart. Ovarian activity, serum concentration of cholesterol, glucose, insulin and reproductive performance variables were recorded. Data were analysed considering treatment (group) and genotype. Supplementation had positive effects on the overall mean serum concentrations of cholesterol (p < 0.05), glucose (p < 0.05) on day 6 of nutritional treatment and insulin (p = 0.07) on day 8. Fat supplementation did not affect the total number of follicles, follicle populations and ovulation rate. However, fat-supplemented Rahmani ewes tended to have higher ovulation rate compared with other breeds (treatment × breed interaction, p = 0.06). Treatment also did not affect the mean concentration of serum estradiol or progesterone. Supplemented ewes had higher conception (p = 0.06) and lambing rates (p < 0.05) compared with control. In conclusion, short-term supplementation with rumen-protected fat as a source of energy around breeding time improved metabolism, conception and lambing rates of ewes without effects on steroidogenic capacity and ovarian activity being apparent.

Effect of season, month of parturition and lactation on estrus behavior and ovarian activity in Barki x Rahmani crossbred ewes under subtropical conditions

The correlations between some meteorological parameters and fertility data were evaluated in Barki x Rahmani crossbred ewes using the records of five consecutive years (2003-2007). Additionally, estrus detection and ultrasonic evaluation were applied on eighteen mature dry ewes during breeding and non-breeding seasons. The effect of lactation was evaluated by monitoring estrus behavior in ninety four lactating ewes from 40 to 120 d after parturition. Moreover, ultrasonography was used to identify ovarian activity in six cyclic and six acyclic non-lactating ewes. Results revealed that relative estrus occurrence and fertile mating were positively correlated (P <0.05) with high temperature and long photoperiod (conditions of summer season), and were negatively correlated (P < 0.01) with rainfall (condition of winter season). During breeding season, estrus rate, serum progesterone concentration, and diameter of largest follicle were significantly (P < 0.05) higher than those observed during the non-breeding season. Furthermore, month of parturition had a significant effect (P < 0.05) on estrus rate of lactating ewes where ewes that lambed in August, September, and October recorded higher estrus rate than those lambed in November and December. However, the lactational strength did not exert any deleterious effect on the reproductive performance of lactating ewes. In conclusion, in Egypt under subtropical conditions, Barki x Rahmani crossbred ewes exerted optimum estrus behavior and fertile mating during summer season. The reduction in estrus activity during lactation was due to the seasonal effect rather than lactational stress.