Metabolic and immunological changes in transition dairy cows: A review

Smooth transition from pregnancy to lactation is important for high productive and reproductive performance during later postpartum period in dairy animals. On the other hand, the poor transition often leads to huge economic loss to dairy farmers due to compromised production and reproduction. Therefore, understanding the causes and consequence of metabolic changes during the transition period is very important for postpartum health management. In this review, metabolic changes with reference to negative energy balance in transition cow and its effect on health and reproduction during the later postpartum period in dairy animals are discussed besides the role of metabolic inflammation in postpartum performance in dairy animals.

Effect of recombinant and native buffalo OVGP1 on sperm functions and in vitro embryo development: a comparative study

Background

An oviduct- specific glycoprotein, OVGP1, is synthesized and secreted by non-ciliated epithelial cells of the mammalian oviduct which provides an essential milieu for reproductive functions. The present study reports the effects of recombinant buffalo OVGP1 that lacks post-translational modifications, and native Buffalo OVGP1 isolated from oviductal tissue, on frozen- thawed sperm functions and in vitro embryo development.

Results

The proportion of viable sperms was greater (P < 0.05) in the recombinant OVGP1-treated group compared to the native OVGP1-treated group at 2 h, 3 h, and 4 h of incubation. The proportion of motile sperms at 3 h and 4 h of incubation; and membrane- intact sperms at 4 h was greater (P < 0.05) in the native OVGP1-treated group compared to the control and recombinant OVGP1-treated groups. The proportion of capacitated and acrosome- reacted sperms was greater (P < 0.05) in the native OVGP1-treated group compared to the recombinant OVGP1 group at 4 h. The rates of cleavage of embryos and their development to the blastocyst stage were greater (P < 0.05) in the presence of either native or recombinant OVGP1 in comparison to control at 10 μg/mL concentration as compared to 5 or 20 μg/mL.

Conclusions

The study suggests that both native and recombinant OVGP1 impart a positive effect on various sperm features and in vitro embryo development. However, native OVGP1 was found to have a more pronounced effect in comparison to recombinant non-glycosylated OVGP1 on various sperm functions except viability. Hence, our current findings infer that glycosylation of OVGP1 might be essential in sustaining the sperm functions but not the in vitro embryo development.

Electronic supplementary material

The online version of this article (doi:10.1186/s40104-017-0201-5) contains supplementary material, which is available to authorized users.

Influence of clinical mastitis and its treatment outcome on reproductive performance in crossbred cows: A retrospective study

Aim:

Evaluation of the effect of clinical mastitis (CM) and its treatment outcome on the reproductive performance in crossbred cows retrospectively.

Materials and Methods:

Datasets of 835 lactating cows affected with CM during a period of 12 years (2001-2012) were considered for this study. Mastitis treatment related data and reproductive parameters such as days to first detected heat (DTFDH), days to first insemination (DTFI), days open (DO), and number of services per conception (SC) were collected from mastitis treatment and artificial insemination registers, respectively. Data were analyzed by ANOVA using SPSS 20 software. The means were compared with the Duncan’s multiple comparison post-hoc test.

Results:

CM affected cows had significantly (p<0.05) higher DTFDH, DTFI, DO and SC compared to clinically healthy cows. Cows diagnosed with a single episode of CM had significantly (p<0.05) delayed DTFDH while, DO and SC were significantly higher (p<0.05) in cows diagnosed by multiple episodes of CM. SC was significantly (p<0.05) higher in cows diagnosed with both relapse and recurrence. Severe CM affected cows had significantly (p<0.05) altered reproductive parameters. The reproductive parameters were altered to high extent when CM occurred during the breeding period.

Conclusion:

CM-affected cows had higher DTFDH, DTFI, DO and SC compared to clinically healthy cows. The negative effects of CM on reproduction parameters were higher when CM occurred during the breeding period.

198 SUCCESSFUL TRANSPLANTATION OF BUFFALO (Bubalus bubalis) GERM CELLS TO HOMOLOGOUS RECIPIENTS

Transplantation of isolated germ cells from a fertile donor male into the seminiferous tubules of infertile recipients can result in donor germ cells-derived sperm production. This technique has the potential to be used as an alternative strategy for producing transgenic livestock with higher efficiency and less time and capital requirement than the current methods. The objective of the present study was to investigate whether the homologous transplantation of isolated buffalo germ cells could result in colonization of recipient testes. Germ cells were isolated from prepubertal buffalo testes (4–6 months of age) by using double enzymatic digestion method and filtration through 80- and 60-µm nylon mesh filters. Further enrichment was achieved by differential plating on Datura stramonium agglutinin lectin-coated dishes and after that Percoll density gradient centrifugation as descrived by van Pelt et al. (1996) with minor modifications. A discontinuous density gradient was prepared with 60, 50, 40, 36, 34, 32, 30, 28, and 20% Percoll in a 15-mL centrifuge tube. The enriched germ cells were then labelled with red fluorescent linker dye PKH26 (Sigma, St. Louis, MO, USA) as per the manufacturer’s instructions, and ~10 million cells/testis were transferred into the rete testis of 3 recipients (16–18 months of age) under ultrasonographic guidance. After 45 days, testes were surgically removed and samples were prepared for analysis of labelled cells via wet mount of seminiferous tubules and individual cells isolation. When wet mount specimen were observed under a fluorescence microscope, PKH26-positive cells were identified on the seminiferous tubule basement membrane in all 3 recipients, which indicated that these cells had successfully migrated from the tubule lumen and were likely to be donor germ cells. In freshly isolated cells, clumps of PKH26-positive cells were observed, which indicated either cell division or extensive local colonization of specific areas of the seminiferous tubules. In conclusion, we report successful homologous transplantation of germ cells in prepubertal buffalo testes. Further studies will investigate functionality of transferred testicular cells.

Efficiency of uterine fluid cytology in the diagnosis of subclinical endometritis in the water buffalo (Bubalus bubalis)

This study compared endometrial cytology vis-a-vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)-affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE-affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.

Evaluation of salivary electrolytes during estrous cycle in Murrah buffaloes with reference to estrus detection

Aim:

Timely estrus detection is one of the critical factors for increasing reproductive efficiency in buffaloes. In recent decades, saliva has become a more popular as a noninvasive source for determining physiological status of animals by various biochemical electrolytes. This study was designed to assess and correlate changes in different salivary minerals concentration (calcium, inorganic phosphorus, magnesium, sodium, potassium, and chloride) during different stages of the estrous cycle in Murrah buffaloes.

Materials and Methods:

The saliva samples were collected during the different phases of the estrous cycle from 20 Murrah buffaloes in early morning hours and were assayed using respective minerals assay kits.

Results:

The concentrations of calcium (8.76±0.08-12.11±0.11 mg/dl), inorganic phosphorus (6.56±0.13-14.72±4.50 mg/dl), magnesium (2.27±0.14-5.79±0.15 mg/dl), sodium (139.47±0.31-159.62±1.22 mmol/L), potassium (12.40±0.22-26.85±1.22 mmol/L), and chloride (109.28±0.41-137.07±0.68 mmol/L) varied during the different phases of estrous cycle. The concentration of calcium, inorganic phosphorus, magnesium, sodium, potassium, and chloride in saliva were significantly (p<0.01) higher during estrus phase compared to other phases of the estrous cycle. All these minerals were positively and significantly (p<0.0001) related to estrogen concentration while salivary concentrations of calcium, magnesium, sodium, and chloride showed a significant (p<0.0001) negative correlation with progesterone level in blood plasma.

Conclusion:

These preliminary findings indicate that there are definite variations in salivary mineral and electrolyte concentrations during different phases of the estrous cycle. These results may be used as an aid for estrus detection/confirmation in buffaloes although validation of the results using a large number of animals is required.

Cryopreservation of bull semen: Evolution from egg yolk based to soybean based extenders

Since the inception of bovine semen cryopreservation, egg yolk and milk based extenders have been used to protect sperm from the detrimental effects of cooling and freezing. In recent years, demand for alternatives to conventional commercial extenders has arisen as the risk of introducing exotic diseases through transporting egg yolk based products has been recognized. Egg yolk can also interfere with sperm evaluation and the presence of particulate material in the extender may reduce fertility. Soybeans contain lecithin, a phospholipid fraction that can substitute for high molecular weight lipoprotein and phospholipids from egg yolk and prevent or ameliorate damage to the sperm plasma membrane that occurs during extension, cooling, and cryopreservation. Soy lecithin based extenders have been evaluated for processing and freezing bovine semen, although extender from soybean milk has not been studied as extensively. Commercially available soy lecithin based extenders are used increasingly but remain under scrutiny and are not universally accepted. With these observations in mind, this review is intended to examine effects of conventional cryopreservation procedures, methods of assessment, and potential for developing soybean extract as an acceptable alternative to traditional egg yolk and milk based extenders for bull sperm cryopreservation.

Identification of suitable combinations of in vitro sperm-function test for the prediction of fertility in buffalo bull

The present study assessed sperm functional characteristics in the frozen-thawed semen of buffalo bulls and estimated their relationship with field fertility. Frozen semen samples from three different freezing operations each from nine Murrah buffalo bulls were used for the assessment of different sperm functions related to fertilizing potential. Bulls were classified into high (n = 2), medium (n = 5), and low (n = 2) fertile based on adjusted field fertility. The sperm functions estimated included membrane integrity using carboxyfluorescein diacetate-propidium iodide, acrosome reaction status using fluorescein isothiocyanate peanut agglutinine, status of apoptosis using Annexin-V, protamine deficiency using Chromomycin A₃, membrane stability using Merocyanine 540 and lipid peroxidation status using 4, 4-difluoro-4-bora-3a, 4a-diaza-s-indacene. The relationship between the proportion of live acrosome-intact spermatozoa and fertility was positive and significant (r = 0.59; P = 0.001). The proportion of moribund spermatozoa showed a significantly negative correlation with fertility (r = -0.50; P = 0.008). Similarly, the relationship of spermatozoa with unstable membrane (r = -0.51; P = 0.007), necrotic (r = - 0.42; P = 0.028), early necrotic (r = -0.42; P = 0.031), and apoptotic spermatozoa (r = -0.39; P = 0.046) with bull fertility was negative and significant. The correlation between the protamine-deficient spermatozoa and fertility was negative, but not significant. Among different combinations of tests, live acrosome-intact spermatozoa and lipid peroxidation status of spermatozoa revealed high positive correlation with buffalo bull fertility (adjusted R² = 0.73, C[p] = 0.80). These preliminary findings may help in developing tools for assessing fertility of buffalo bulls, once validated in more animals.

Cellular and molecular mechanisms involved in placental separation in the bovine: A review

Retention of fetal membranes (RFM), where the fetal placenta is not expelled within 8-12 hr after calving, lowers bovine productivity and fertility, resulting in significant economic loss to the dairy industry. Several risk factors that predispose an individual to RFM are known, but a unifying pathogenesis remains elusive due to its multifactorial etiology. Fetal membrane separation and expulsion after parturition involves structural and immunological changes of the bovine placentome that are governed predominantly by steroid hormones and the prostaglandin milieu of late pregnancy and parturition. Maturation of the placentome, a gradual and concerted event of late gestation, is likely initiated by the up-regulation of fetal major histocompatibility complex class I in the interplacentomal region-which increases the apoptosis of binucleate and other trophoblastic cells, the degradation of collagen in the extracellular matrix by matrix metalloproteinases, and an influx of phagocytic leukocytes. Shear force further distorts the crypt architecture of the mature placentomes when they are forced against the fetus during the second stage of labor. Cotyledon dehiscence from the caruncular crypts is completed following fetal expulsion as a result of acute shrinkage of the cotelydonary villi as well as reduced perfusion to the caruncle; the secundinae is expelled by uterine contractions. A better understanding of placentomal maturation, intra-partum, and immediate postpartum changes of the placentome should help develop strategies for the treatment and prevention of RFM. The present review proposes a model of placentome maturation and separation of fetal membranes in the dairy cow.

Potential of acute phase proteins as predictor of postpartum uterine infections during transition period and its regulatory mechanism in dairy cattle

Among the various systemic reactions against infection or injury, the acute phase response is the cascade of reaction and mostly coordinated by cytokines-mediated acute phase proteins (APPs) production. Since APPs are sensitive innate immune molecules, they are useful for early detection of inflammation in bovines and believed to be better discriminators than routine hematological parameters. Therefore, the possibility of using APPs as a diagnostic and prognostic marker of inflammation in major bovine health disorders including postpartum uterine infection has been explored by many workers. In this review, we discussed specifically importance of postpartum uterine infection, the role of energy balance in uterine infections and potential of APPs as a predictor of postpartum uterine infections during the transition period and its regulatory mechanism in dairy cattle.

Episodes of clinical mastitis and its relationship with duration of treatment and seasonality in crossbred cows maintained in organized dairy farm

Aim:

Present study aimed to evaluate the different episodes of clinical mastitis (CM) and influence of duration of treatment and seasonality on the occurrence of different episodes of CM in crossbred cows.

Materials and Methods:

A total of 1194 lactation data of crossbred CM cows were collected from mastitis treatment record from 2002 to 2012. Data of CM cows were classified into types of episodes (pattern of repeated or multiple episodes occurrence) and number of episodes (magnitude of multiple cases). Types of episodes were divided as single (clinical cure by a single episode of treatment), relapse (retreatment of the same cow within 21 days), recurrence (new CM at least 21 days after treatment), and both (relapse and recurrence). The season was classified as winter (December to March), summer (April to June), rainy (July to September), and autumn (October to November). The difference between incidences of different types of CM episodes and the association between number or type of CM episodes with duration of treatment and seasons of CM occurrence were analyzed by Chi-square test.

Results:

Among 1194 animals suffered with CM, 53, 16, and 18% had the single episode, relapse, and recurrence, respectively; while 13% suffered by both relapse and recurrence. We estimated the duration of treatment and found 80% of the cows treated 1-8 days, in which 65% treated for 1-4 days, while 35% cows were treated for 5-8 days. Further, 12% cows treated for 9-15 days and 7.5% cows treated >15 days. The relationship between duration of treatment and different episodes of CM revealed that 1-8 days treated cows were mostly cured by the single episode with less relapse and recurrence. In contrast, the incidences of recurrence and relapse episodes were higher in cows treated for more than 9 days. The highest incidence of relapse was noticed in winter (36%) than other seasons (10-28%), while the recurrence was less during autumn (9%) compared to other seasons (20-40%).

Conclusion:

Cows those suffered by both relapse and recurrence were more susceptible to CM, and they need to be culled from farm to control the transmission of infections. Although the influence of seasonality was difficult to understand, the higher magnitude of relapse and recurrence during winter suggested the adverse effects of cold stress on treatment outcome.

Metabolic indicators for retention of fetal membranes in Zebu and crossbred dairy cattle

The present study assessed the peripartum metabolic profile of Karan Fries crossbred (Holstein Friesian × Tharparkar) and Zebu (Sahiwal) cows in relation to expulsion of fetal membranes. Peripheral blood concentrations of glucose, total protein, total cholesterol, blood urea nitrogen, non-esterified fatty acid (NEFA) and β-hydroxy butyric acid (BHBA) were determined (from 30 days before and 2 days after calving) in cows that expelled fetal membranes normally (n = 13; 7 crossbred and 6 Zebu cows) and in cows that developed retention of fetal membranes (RFM; n = 13; 7 crossbred and 6 Zebu cows). In both breeds, the cows that developed RFM had significantly lower concentrations of cholesterol, glucose and total protein, while the concentrations of NEFA, BHBA and blood urea nitrogen were significantly (P < 0.05) higher than those in cows that normally expelled the fetal membranes. In crossbred cows affected with RFM, the concentrations of NEFA increased significantly (P < 0.05) from Day 14 prepartum to Day 2 postpartum and the concentrations of BHBA increased from Day 7 prepartum to Day 2 after calving. Similarly, in Zebu cows, NEFA and BHBA concentrations increased significantly (P < 0.05) between Day 5 prepartum and Day 2 postpartum in RFM cows. Using receiver operator characteristic analysis, we observed that the concentrations of NEFA and BHBA before calving were highly related to the RFM. It may be inferred that monitoring the levels of NEFA and BHBA during prepartum period would help in identifying the cows at the risk of developing RFM.

Morphometric evaluation of seminiferous tubule and proportionate numerical analysis of Sertoli and spermatogenic cells indicate differences between crossbred and purebred bulls

Aim:

The present study compared the testicular cytology and histology between crossbred (Holstein–Friesian [HF] × Tharparkar) and purebred (HF and Tharparkar) bulls to find out differences if any.

Materials and Methods:

Four peripubertal bulls from each breed were utilized for the study. Through percutaneous needle aspiration biopsy, Sertoli and spermatogenic cells were extracted, and morphometry was studied. For histological studies, testicular tissues obtained through unilateral castration were utilized. Sertoli cells specific GATA4 antibody was used to study the population of Sertoli cells in the seminiferous tubule through immunofluorescence.

Results:

The testicular weight, volume, and scrotal circumference differed significantly among the breeds. The diameter and area of the seminiferous tubule was high in HF, followed by Karan Fries (KF), and Tharparkar bulls. However, the degree of compactness, based on qualitative evaluation, was high in Tharparkar followed by KF and HF bulls. The intensity of Leydig cells was higher in Tharparkar bulls followed by KF and HF. The proportion of Sertoli cells was higher (p<0.05) in HF and Tharparkar bulls compared to KF bulls.

Conclusion:

It may be concluded that variations exist in testicular components of the breeds studied and the proportion of Sertoli cells in relation to spermatogenic cells was significantly lower in crossbred bulls compared to purebred bulls.

Modulation of post-partum reproductive performance in dairy cows through supplementation of long- or short-chain fatty acids during transition period

Thirty-six cross-bred cows were used to study the effect of long-chain (flaxseed) or short-chain (butyric acid) fatty acid supplementation on metabolic status, ovarian function and reproduction performance during transition period. Control cows received a routine feed of transition diet, while the cows in two treatment groups were supplemented with either 750-g crushed flaxseed or 250 g butyric acid per cow per day. Ovarian activity was monitored by transrectal ultrasonography on 10th, 20th and 30th days post-partum. Blood samples were collected by jugular venipuncture into heparinized polystyrene tubes; plasma was prepared and stored under -20 °C until analysis. Results indicated that cows in flaxseed group were in positive energy balance as indicated by lower NEFA and Beta hydroxy Butyrate and higher glucose concentrations. Uterine involution was completed well within 30 days post-partum in all the cows in flaxseed fed group compared to 76.9% in butyric acid supplemented and 61.5% in control groups. The size of dominant follicle and corpus luteum was significantly higher (p < 0.05) for flaxseed group compared to control group, which in turn resulted in higher concentrations of plasma progesterone. Cows fed on diets supplemented with flaxseed exhibited post-partum heat earlier and bred sooner (p < 0.05) than control cows. It has been noticed that supplementation of flaxseed and butyric acid enhanced involution of uterus, early resumption of cyclicity and thereby early breeding. However, in view of the encouraging results obtained for flaxseed supplemented group, its organic nature and easier availability at farmer's gate, we concluded that flaxseed can be safely included in transition diet to modulate reproductive performance of dairy cattle.

Relationship of conventional and fluorescent microscopic technique to assess in vitro semen quality status of Murrah buffalo males

In vitro fertility assessment using fluorescent technique is a better predictor of fertility status of bulls as compared to traditional semen quality assessment techniques, therefore, the study was planned to assess in vitro fertility status of bulls based on conventional and fluorescent techniques. Seventy-three ejaculates were collected from 12 Murrah buffalo bulls maintained at Artificial Breeding Research Centre, NDRI, Karnal, India for the experiment and subjected to statistical analysis using SYSTAT. The mean values of ejaculate volume (ml), mass activity, individual motility (%), sperm concentration (millions/ml), live sperm (%), total abnormalities (%), HOST (%) and acrosomal integrity (%) were 2.70 ± 0.28, 2.8 ± 0.14, 63.8 ± 2.16, 1749.7 ± 122.24, 77.3 ± 2.48, 6.2 ± 0.51, 75.1 ± 1.81 and 84.5 ± 2.26, respectively. The repeatability estimates were significant (P<0.05) for ejaculate volume (0.34 ± 0.137), acrosomal integrity (0.29 ± 0.134) and live percentage (0.28 ± 0.133), indicating sufficient bull to bull variation for the parameters. The mean values of seminal attributes of fluorescent based criteria of CMA3 (Chromomycin A3), SYBR-PI and FITC-PNA (fluorescent isothiocynate-conjugated peanut agglutinin) were 5.25 ± 0.41, 67.91 ± 1.24 and 82.00 ± 1.25 percent, respectively. Bulls were ranked on the basis of expected producing ability (EPA) for semen characteristics assessed by conventional and fluorescent criteria. Rank correlations were found to be significant for FITC with most of the parameters evaluated by conventional methods. In conclusion, among the conventional criteria, individual motility (%) revealed ranking of bulls almost similar to that of fluorescent criteria.