Studies on the growth performance of different broiler strains at high altitude and evaluation of probiotic effect on their survivability

Gut bacteriome dynamics in high altitude-adapted chicken lines: a key to future poultry therapeutics

High-altitude-adapted chickens harbor a unique gut bacteriome essential for their survival under extremely cold and hypoxic environment, however, little is known about their population and functional dynamics, limiting their application in poultry production. Hence, this study employed amplicon-based metagenomics to examine the gut bacterial diversity and their functional profile in two high-altitude-adapted chicken lines, e.g. LEHBRO-1 and LEHBRO-3. The results revealed significant variations in taxonomic abundance at the phylum level, with Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria predominating in LEHBRO-1, whereas Firmicutes, Proteobacteria, Bacteroidetes, Planctomycetes, and Actinobacteria predominated in LEHBRO-3. Genus-level diversity and Linear Discriminant Analysis Effect Size (LEfSe) biomarker analysis also substantiated the differences in the gut bacterial communities between the two chicken lines. Furthermore, functional profiling revealed enrichment of carbohydrate, nucleotide, lipid, amino acid, fatty acid, energy, and glycan metabolic pathways in the gut bacteriomes of these high-altitude chicken lines. The Statistical Analysis of Metagenomic Profiles (STAMP) for metabolic profiling identified a significant difference in purine and protein metabolism between these two chicken lines. These findings indicate the unique gut bacteriome and their functional diversity in high-altitude-adapted chickens, which would provide a foundation for future research on gut therapeutics to improve chicken health and productivity in high-altitude areas.

Stachyose in combination with L. rhamnosus GG ameliorates acute hypobaric hypoxia-induced intestinal barrier dysfunction through alleviating inflammatory response and oxidative stress

High altitude is closely related to intestinal mucosal damage and intestinal microbiota imbalance, and there is currently no effective prevention and treatment measures. In this study, the effects of stachyose (STA), L. rhamnosus GG (LGG) and their combination on inflammatory response, oxidatve stress and intestinal barrier function in mice exposed to acute hypobaric hypoxia were investigated. Our results indicated the combination of STA and LGG could more effectively regulate intestinal microbiota disorders caused by hypobaric hypoxia than STA or LGG alone. When mice were administered with STA + LGG, the content of short chain fatty acids (SCFAs) especially butyric acid significantly increased, which helped intestinal cells to form tight connections, improve the level of anti-inflammatory cytokine (TGF-β) and antioxidant enzymes (SOD, CAT, GSH-Px), and decrease the expression of pro-inlammatory cytokines and hypoxia-inducing factors (IFN-γ, IL-1β, IL-6, TNF-α and HIF-1α), thereby enhance the strong intestinal barrier function. Furthermore, the synbiotics significantly reduced the ratio of Firmicutes to Bacteroidetes, while significantly increased the relative abundance of Rikenella, Bacteroides, Odoribacter, Ruminiclostridium_5 and Gordonibacter, which were correlated with production of SCFAs and anti-inflammatory role. Correlation analysis showed that the protective effect of synbiotics on intestinal barrier function was associated with its anti-inflammatory activity and antioxidant capacity. It provided a strong foundation for further research on the role of STA and LGG in maintaining normal intestinal function at high altitude. Our study has identified and demonstrated a new synbiotic that may be one of the ideal intervention measures for preventing and treating intestinal dysfunction at high altitude.

Selection and evaluation of lactic acid bacteria from chicken feces in Thailand as potential probiotics

Background

Lactic acid bacteria (LAB) are widely used as probiotics in poultry production due to their resilience to low pH and high bile salt concentrations, as well as their beneficial effects on growth performance and antagonistic activity against enteric pathogens. However, the efficacy of probiotics depends on strain selection and their ability to colonize the host's intestine. This study aimed to select, identify, and evaluate LAB strains isolated from chicken feces in Thailand for potential use as probiotics in the chicken industry.

Methods

LAB strains were isolated from 58 pooled fresh fecal samples collected from chicken farms in various regions of Thailand, including commercial and backyard farms. Gram-positive rods or cocci with catalase-negative characteristics from colonies showing a clear zone on MRS agar supplemented with 0.5% CaCO3 were identified using MALDI-TOF mass spectrometry. The LAB isolates were evaluated for acid (pH 2.5 and pH 4.5) and bile salt (0.3% and 0.7%) tolerance. Additionally, their cell surface properties, resistance to phenol, antimicrobial activity, hemolytic activity, and presence of antimicrobial resistance genes were determined.

Results

A total of 91 LAB isolates belonging to the Pediococcus, Ligilactobacillus, Limosilactobacillus, and Lactobacillus genera were obtained from chicken feces samples. Backyard farm feces exhibited a greater LAB diversity compared to commercial chickens. Five strains, including Ligilactobacillus salivarius BF12 and Pediococcus acidilactici BF9, BF14, BYF20, and BYF26, were selected based on their high tolerance to acid, bile salts, and phenol. L. salivarius BF12 and P. acidilactici BF14 demonstrated strong adhesion ability. The five LAB isolates exhibited significant cell-cell interactions (auto-aggregation) and co-aggregation with Salmonella. All five LAB isolates showed varying degrees of antimicrobial activity against Salmonella strains, with P. acidilactici BYF20 displaying the highest activity. None of the LAB isolates exhibited beta-hemolytic activity. Whole genome analysis showed that L. salivarius BF12 contained ermC, tetL, and tetM, whereas P. acidilactici strains BF9 and BF14 carried ermB, lnuA, and tetM.

Conclusion

The selected LAB isolates exhibited basic probiotic characteristics, although some limitations were observed in terms of adhesion ability and the presence of antibiotic resistance genes, requiring further investigation into their genetic location. Future studies will focus on developing a probiotic prototype encapsulation for application in the chicken industry, followed by in vivo evaluations of probiotic efficacy.

Growth performance, survivability and profitability of improved smallholder chicken genetics in Nigeria: A COVID-19 intervention study

The impact of COVID-19 pandemic on smallholder farming households (SFH) includes increased poverty, and loss of livelihoods. Provision of livestock to SFH is a helpful intervention to mitigate this impact. This study provided a total of 150 smallholder poultry farmers, randomly selected from three states (Kebbi, Nasarawa, and Imo) in Nigeria, with ten 5-week-old chickens (mixed sexes) each, of either FUNAAB Alpha or Noiler chicken genetics. The improved, dual-purpose chickens were evaluated for growth performance (GP), survivability and profitability. The birds were managed under semi-scavenging production system. Body weight, mortality, and cost of production (COP) were recorded every 4 weeks until 21 weeks of age. Profitability was a function of the COP, and the selling price for live-birds (cocks). Body weight of Noiler (1,927 g) birds was not significantly (p > .05) higher than FUNAAB Alpha (1,792 g) at 21 weeks. Agroecology and genetics had significant (p < .05) effects on GP and survivability. Survivability of FUNAAB Alpha was higher (p < .05) than Noiler, with Nasarawa (81%-96%), having the highest (p < .0001) survival rate compared to Imo (62%-81%), and Kebbi (58%-75%). At 21 weeks, the number of cocks and hens differed significantly (p < .05) within the states (Imo: 2.4 ± .2 and 5.4 ± .3; Kebbi: 2.6 ± .2 and 5.5 ± .3; and Nasarawa: 2.9 ± .2 and 5.8 ± .3). Nasarawa (NGN 7,808; USD 19) ranked best for profitability, followed by Kebbi (NGN 6,545; USD 16) and Imo (NGN 5,875; USD 14). Overall, this study demonstrates that provision of improved chickens to vulnerable SFH in Nigeria holds great potential for economic growth, and resilience during emergencies, such as the COVID-19 pandemic.

A survey on backyard poultry farming in Leh-Ladakh region

Leh-Ladakh, India is situated at 3000-3500 m above mean sea level, where harsh climatic environment is characterized by hypobaric-hypoxia, low humidity, high UV radiation and extreme variation in ambient temperature (-20 to +30ºC), which causes high-altitude stress to poultry. Hence, not much progress has been made in poultry rearing in this region, as high altitude causes high mortality and poor growth resulting in heavy loss of farm economy. The present field survey was conducted to study the farmer’s choice, existing farm resources, market opportunity, and social awareness on modern poultry rearing. Hence, many villages, viz. Chuchot, Shey, Phyang, Thicksey, Basgo, Skurbuchan, Skara, Ranbirpura of Leh-Ladakh were surveyed. The survey findings indicated that few progressive farmers are practicing backyard poultry rearing which plays an important role in the rural economy and women empowerment. It was found that the average flock size reared per family was small and farmers preferred colour plumage birds. The coops for chicken are mainly made up of double walled under or semi-underground mud houses for better insulation and heat retention during winter. Shelters are provided during night, whereas pasture or open field gazing is practiced during day time even in winters. Farmers rear birds throughout summers and self-consume or even sell them in three to four times higher price during winters when the demand is very high. Poultry farming among more farmers in more villages with help from state departments and different NGO will definitely strengthen poultry farming in this region. DIHAR (Defence Institute of High Altitude Research) a premium institute, also working in poultry science can further help these farmers in providing a complete package of basic training on management practices and even in distribution of high altitude adapted chicks to uplift farmer’s interest and promote poultry farming in this region.

Effect of Novel Lactobacillus paracaesi microcapsule on growth performance, gut health and microbiome community of broiler chickens

The beneficial action of probiotics is questioned time and again due to the loss of their survivability under gastrointestinal conditions, particularly gastric acid. In this experiment, a probiotic species was encapsulated to improve its delivery to the distal parts, and its effects on production performance, gut health, and microbial profile in broilers were investigated. A total of 240 Arbor acres (AA) broilers were randomly allotted into 3 treatments with 8 replicate pens per treatment and 10 broilers in each pen for 42 d. Dietary treatments were 1) basal feed without any additives (CON), 2) CON+15 ppm Virginiamycin (ANT), and 3) CON+500 ppm encapsulated Lactobacillus paracaesi (ELP). The result showed that the addition of ELP to the feed did not affect growth performance and carcass characteristics significantly. However, ELP increased the ratio of villus height to crypt depth (P < 0.05) and mRNA expression of ZO-1 (P < 0.05) relative to the CON or ANT group. Similarly, qPCR showed that dietary supplementation of ELP raised gene expression of the anti-inflammatory cytokine and tended to decrease proinflammatory cytokines resulting improve in immunity. Moreover, chicks fed with ELP had lower malondialdehyde (MDA) (P < 0.05) than CON and lower reactive oxygen species (ROS) (P < 0.05) level than ANT in serum. In contrast, the total antioxidant capacity (TAOC) level was tended to increase. The ammonia level of ileum and cecum chyme was decreased (P < 0.05) in the ELP group than CON while the level of propionic acid of cecal content was increased (P < 0.05). 16S rRNA sequencing revealed the dietary treatment modulated the diversity and composition of cecal microflora. At the phylum level, Bacteroidetes was enriched, and Proteobacteria was depleted in the ELP group. At the genus level, ELP increased Bacteroides (P < 0.05) compared to control. The results indicate that oral delivery of probiotics via microcapsule could impart beneficial effects on birds and be used as an alternative to antibiotics.

Managing broiler production challenges at high altitude

This review covers the challenges of broiler chickens at high altitude, with the focus on growth performance and physiological response. The review also sheds light on nutritional and management interventions that help overcome the challenges raised at high altitude. Reduced concentration of atmospheric oxygen is by far the biggest challenge that remarkably affect growth performance and livability of broiler chickens reared in high altitude area. Broiler chickens have endured intensive genetic selection, which potentially predispose them to several metabolic disorders. Hypoxia is an overriding factor that may increase the incidence of metabolic disorders, mainly ascites syndrome at high altitude. Commercial broiler strains cannot fully achieve their genetic potential when raising at highland regions. Careful nutrition and management considerations are required to prevent metabolic disorders when raising broilers at high altitude. In ovo or in‐feed nutraceuticals such as l‐carnitine and guanidinoacetic acid as well as pharmaceuticals, texture of feed and the use of proper sources and levels of dietary energy and protein are important factors that need to be carefully considered for rearing broiler chickens at high altitude. Management strategies such as lighting programs have been shown to be effective to circumvent ascites prevalence. Special breeding programs may also be considered to develop strains with resistance to ascites.

Meta-Analysis and Systematic Review of the Thermal Stress Response: Gallus gallus domesticus Show Low Immune Responses During Heat Stress

Heat stress, which affects broiler growth performance and immunity, is a major concern in the poultry industry. This meta-analysis aimed to demonstrate the significant effect of heat stress on broiler mass gain and immunoglobulin levels, which regulates the mortality rate of broilers. A total of 2,585 studies were downloaded from PubMed, Web of Science, and Google Scholar from January 1, 2015, to September 1, 2021. Eventually, 28 studies were selected based on specific criteria. The results for body mass gain, total mass of immune organs (thymus, spleen, and bursa of Fabricius), immunoglobulin (IgA, IgG, and IgM) levels, and mortality rate were analyzed using odds ratio or the random-effects model (REM) at a confidence interval (CI) of 95%. Compared to the control, heat stress significantly decreased body mass gain (10 trials: REM = 1.35, 95% CI: 1.21, 1.50). Compared to that in the control, heat stress significantly increased immunoglobulin levels: IgA (7 trials: REM = 1.69, 95% CI: 0.90, 3.16), IgG (6 trials: REM = 1.24, 95% CI: 0.85, 1.81), IgM (8 trials: REM = 0.69, 95% CI: 0.44, 1.08), and heat stress also increased the broiler mortality rate (6 trials: REM = 0.06, 95% CI: 0.01, 0.27). However, there were no significant changes in the immune organs between the control and heat-stressed groups. In conclusion, heat stress remarkably alters the mass gain and immunoglobulin levels of broilers, which may be a cause of the high mortality rate.

Evaluation of metabolic syndromes and parasitic infection in Muscovy ducks under different management conditions

Proper health management is essential for productivity in duck farming. However, there is limited information on the effect of management conditions on rates of metabolic problems and parasitic infections in anatids. We evaluated the rates of metabolic syndromes and gastrointestinal parasite involvement in Muscovy ducks up to 12 weeks of age, under 3 management conditions: backyard, organized, and organized with probiotics. Individuals under organized management developed 2 metabolic problems: ascites, which was rare (3.5%), fatal, and affected both males and females, and angel wing syndrome, which was more frequent (10.6%), has low impact on general health, and only affected males. The treatments do not have a significant effect on the development of ascites, but only individuals in controlled conditions presented this syndrome, and due to its low prevalence, further studies with a larger sample size are required. The risk of angel wing syndrome increased significantly with probiotic supplementation. Regarding to parasitic infection, the improvement of sanitary management and the use of probiotics supplementation reduced the occurrence of coccidiosis. Similarly organized management with probiotic supplementation showed a protective effect on helminthiasis by reducing the frequency of Heterakis gallinarum and greatly reducing the helminth egg load. Coccidiosis and helminthiasis infections were not significantly correlated with the final weight of the ducks. Therefore, organized management and the use of probiotics seems to reduce the impact of parasitic infection, although it increases the risk of developing metabolic syndrome.

Dietary Supplementation of Potential Probiotics Bacillus subtilis, Bacillus licheniformis, and Saccharomyces cerevisiae and Synbiotic Improves Growth Performance and Immune Responses by Modulation in Intestinal System in Broiler Chicks Challenged with Salmonella Typhimurium

This study evaluates the effects of probiotics and synbiotics on the performance, immune responses, and intestinal morphology, and the expression of immunity-related genes of broiler chicks challenged with Salmonella typhimurium. Three hundred and sixty broiler chicks were divided into six groups, including broiler chicks challenged and non-challenged with S. typhimurium and fed with probiotic, synbiotic, and basal diet without additive. Growth performance (food intake, daily gain, feed conversion ratio, and mortality), immune responses (antibody titer against sheep red blood cells, immunoglobulins G and M), intestinal morphology, lactic acid bacteria population, and the expression of immunity-related genes (interferon-γ, interleukins 6 and 12, and tumor necrosis factor-α) were investigated. The administration of S. typhimurium decreased growth performance (P = 0.0001), immune responses (P = 0.0001), intestinal morphology (P = 0.0001), lactic acid bacteria population (P = 0.0001), and the expression of immunity-related genes (P = 0.0001) of broiler chickens. However, broiler chicks fed with probiotic (P = 0.001) and synbiotic (P = 0.0001) showed better growth performance, immune responses, intestinal morphology, lactic acid bacteria population, and the expression of immunity-related genes in comparison with infected broiler chicks fed with basal diet lack of probiotic and synbiotic. Feeding probiotics (P = 0.001) and synbiotics (P = 0.0001) showed positive effects for challenged and non-challenged broiler chicks. In sum, feeding synbiotic and probiotic alleviated the negative effects of S. typhimurium on growth and immunity of broiler chicks. It can be suggested to apply synbiotic and probiotics as benefit additive against infectious challenges, such as S. typhimurium.

Evaluation of light colour manipulation on physiological response and growth performance of broiler chickens

Artificial illumination, including light quality, is crucial in modern broiler management. The aim of this study was to examine the effect of a switch in light colour on the performance of broiler chickens in tropical environments. A total of 280 1-day-old Arbor acre male chicks were used for this study and were weighed and assigned to different light environments viz. white (WH), green (GR), blue (BL), GR switched to BL at 14 days (GB), BL switched to GR at 14 days (BG), BL switched to GR at 28 days (BGG) and GR switched to BL at 28 days (GBB) having four replicates of ten birds each. Body weight, weight gain, feed intake and feed conversion ratio were recorded weekly. Blood samples were collected from 2 birds per replicate weekly for the determination of plasma triiodothyronine (T₃), haematology and serum biochemical parameters. The experiment was laid out in a completely randomised design. Results showed that the final body weights of the birds in GBB and GB were comparable but higher than those of the other treatment groups. Feed intake of the chickens in WH was similar to that of BG but higher than those of the other treatment groups, while FCR of the birds in WH was higher (P < 0.05) than the other treatment groups. Plasma T₃ of the birds in GR was comparable to that of birds in BL but significantly higher than those of the birds in WH and a similar trend was also observed at weeks 1 and 2. Heterophil/lymphocyte ratio (H/L) of the birds in WH was significantly higher than those of BL and GR whose values were similar to those in GB and BG. Heterophil/lymphocytes of the birds in WH was higher than those of BG, GR, BGG, GB and GBB but similar to those of BL. The breast muscle of the birds in GBB and GB was similar to those of BGG and GR and significantly higher than those of WH, BL and BG. Based on the results obtained in this study, it was concluded that the use of green light up to 28 days in combination with blue light stimulated the growth of broiler chickens and manipulation of light colours can be used to improve the welfare and performance of chickens.

Evaluation of cardiac status, ascites related factors and growth performance of five commercial strains of broiler chickens

The aim of the current study was to evaluate cardiac status, ascites susceptibility, thyroid hormones, some hematological parameters and performance of five commercial broiler strains. Chicks were selected from strains of Cobb, Hubbard, Ross 308, Arbor Acres, and Arian (Iranian commercial broiler strain). Management and nutritional conditions were the same for all strains. Ascites related factors, and growth performance were measured. The highest and lowest, RV weight/live weight at 21 day of age were related to Arian and Ross 308 strains, respectively (p < 0.05). The TV weight, TV weight/live weight and the RV weight/live weight were significantly different between various strains at 49 and 54 days of age (p < 0.05). Strain had no effect on RV/TV. Performance, T3 and T4 hormones, hematological parameters, and mortalities were not significantly different among the strains (p > 0.05). Ascites mortalities in the Ross 308 was zero; however, it had no significant difference with other strains (p > 0.05). It was concluded that, based on performance and physiological status, even though considered broiler strains did not differ significantly because of the same genetic programs probably, but according to the prices and market conditions each can be selected for breeding.

Morphometric, haematological and physio-biochemical characterization of Bactrian (Camelus bactrianus) camel at high altitude

BACKGROUND

Biochemical and haematological parameters have not been determined in Bactrian camels kept at high altitude. Therefore, this study was undertaken to characterise different physiological, haematological, biochemical, and morphometric parameters of Bactrian camels of high altitude. For this, total fourteen high altitude healthy Bactrian camels were selected from Leh-Ladakh, India, a high altitude area, and thereafter divided into three age groups (N = 3 young; N = 6 adult; N = 5 old camels) to characterise for above parameters. All the results were compared with Lowlander Bactrian camels.

RESULTS

Morphometric measurement showed significant difference in body height, body length, front-hump height and girth, back-hump height and girth, abdomen girth, neck length, and circumference of the shank in the young age group camels as compared to other age groups of Bactrian camels (p < 0.05). Furthermore, all the physiological and haematological parameters were similar in all the age groups of camels (p < 0.05). However, the leukocyte, erythrocyte, Hb, platelets, monocyte, and ESR level were towards the higher side of the normal reference range of Lowlander Bactrian camels. Whereas, the biochemical analysis revealed a significant increase in triglycerides and decrease in protein levels in the younger age group as compared to other age groups (p < 0.05). Although, albumin, aspartate aminotransferase, iron, magnesium, urea, and creatinine levels were insignificant among the different groups, but observed towards the higher side of the low altitude reference range. Interestingly, the glucose levels in all the groups were observed towards the lower side of the range, which showed metabolic adaptation to high altitude.

CONCLUSION

These findings suggested there is morphometric and biochemical variation in Bactrian camel of high altitude. The results further helped in establishing novel reference ranges for these parameters in Highlander Bactrian camel. Hence, this study will be the basis of future research on a Bactrian camel from high-altitude cold desert and helpful for better camel husbandry and health management in high altitude.

Effects of Probiotics as Antibiotics Substitutes on Growth Performance, Serum Biochemical Parameters, Intestinal Morphology, and Barrier Function of Broilers

The aim of this study was to investigate the effects of the combination of probiotics replacing antibiotics on growth performance, serum biochemical parameters, intestinal morphology, and expression of tight junction proteins in intestinal mucosa of broilers. A total of 168 Arbor Acres broilers (45.04 ± 0.92 g) were randomly divided into three treatments, with seven replicates per treatment, and eight broilers per replicate. The experiment included phases 1 (d 0 to 21) and 2 (d 21 to 42). The dietary treatments contained a corn soybean meal-based diet (control group; CON); an antibiotic group (basal diet + 75 mg/kg chlortetracycline; CTC), and a probiotics group (basal diet + probiotics (500 mg/kg in phase 1 and 300 mg/kg in phase 2; Bacillus subtilis 5 × 109 CFU/g, Bacillus licheniformis 2.5 × 1010 CFU/g and Saccharomyces cerevisiae 1 × 109 CFU/g; PB). The results showed broilers fed PB had improved (p < 0.05) feed conversion ratio (FCR) in phase 1 and increased (p < 0.05) average daily gain (ADG) in phase 2, as well as improved (p < 0.05) ADG and FCR overall (d 0 to 42). The apparent total tract digestibility (ATTD) of dry matter, organic matter, gross energy, and crude protein was increased (p < 0.05) in broilers fed PB, while the ATTD of dry matter and organic matter was enhanced in broilers fed CTC compared with CON. Broilers fed PB showed increased (p < 0.05) serum total antioxidant capacity concentrations and tended to have higher (p = 0.06) level of serum immunoglobulin M in phase 1 compared with CON. These broilers also had increased (p < 0.05) level of serum immunoglobulin A in phase 2 in comparison with CON and CTC. Moreover, broilers fed CTC and PB showed increased (p = 0.05) villus height to crypt depth ratio in duodenum, as well as higher (p < 0.05) mRNA expression of zonula occludens-1 in jejunum compared with CON. In conclusion, dietary supplementation with PB as chlortetracycline substitute could improve the growth performance, nutrient digestibility, serum antioxidant capacity, jejunal mucosal barrier function, and intestinal morphology of broilers.

Protective effects of melatonin against fluoride-induced oxidative stress in rats at high altitude

This study was conducted to evaluate the protective effects of melatonin against fluoride-induced oxidative stress-mediated haematological and biochemical changes in rat at high altitude. Adult male Wistar rats (6) were given the basal diet and drinking water ad lib. for first 7-days which was considered as the control period. Thereafter, they were exposed to NaF (@ 50 ppm) per-oral through drinking water for the next 14 days followed by melatonin treatment (@ 15 mg/kg BW, p.o.) for the next 14 days. The result showed induction of oxidative stress during NaF treatment alone, which caused significant increase in alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity, and % inhibition of DPPH, MDA, and water intake. Whereas, total antioxidant capacity (FRAP) and body weight gain were significantly reduced during NaF exposure. Haemogram analysis indicated significant decrease in haemoglobin, packed cell volume, erythrocytes, lymphocytes, platelets count, whereas increase in MCH, monocytes, neutrophil, and eosinophil during NaF exposure. However, melatonin administration after 14 days of fluoride treatment resulted in significant amelioration of adverse changes occurred in different blood-biochemical parameters and also increased the total antioxidant status. Notably, the body weight gain improved during melatonin administration. These findings indicated induction of oxidative stress-mediated adverse change in haematology and biochemical parameters, and amelioration effect of oral dose of melatonin in rats under high altitude stress condition. Hence it can be concluded that melatonin acts as a potent antioxidant agent, which may be orally supplemented for amelioration of fluoride-mediated oxidative stress even under prevalent high altitude stress.

Strategies to modulate the intestinal microbiota and their effects on nutrient utilization, performance, and health of poultry

Poultry is widely produced and consumed meat globally. Its demand is expected to continue increasing to meet the animal protein requirement for ever-increasing human population. Thus, the challenge that poultry scientists and industry face are to produce sufficient amount of poultry meat in the most efficient way. In the past, using antibiotics to promote the growth of poultry and manage gut microbiota was a norm. However, due to concerns over potential fatalistic impacts on food animals and indirectly to humans, their use as feed additives are banned or regulated in several jurisdictions. In this changed context, several alternative strategies have been proposed with some success that mimics the functions of antibiotics as growth promoters and modulate gut microbiota for their beneficial roles. These include the use of probiotics, prebiotics, organic acids, and exogenous enzyme, among others. Gut microbiota and their metabolic products improve nutrient digestion, absorption, metabolism, and overall health and growth performance of poultry. This paper reviews the available information on the effect of feed additives used to modulate intestinal microbiota of poultry and their effects on overall health and growth performance. Understanding these functions and interactions will help to develop new dietary and managerial strategies that will ultimately lead to enhanced feed utilization and improved growth performance of poultry. This review will help future researchers and industry to identify alternative feed ingredients having properties like prebiotics, probiotics, organic acids, and exogenous enzymes.

Hippophae rhamnoides as novel phytogenic feed additive for broiler chickens at high altitude cold desert

Extremes of climate and hypobaric hypoxia cause poor growth performance in broiler chickens at high altitude. The present study examined the potential of Hippophae rhamnoides extract as phytogenic feed additive for broilers reared at 3500 m above mean sea level (MSL). Higher content of phytomolecules were recorded during characterization of the extract. Immunomodulatory activity of extract was observed in chicken lymphocytes through in-vitro studies. Thereafter, for in vivo study, 105 day old Rhode Island Red (RIR) Cross-bred chicks were randomly distributed in to control and treatments T1, T2, T3, T4, T5, and T6 which were supplemented with H. rhamnoides aqueous extract along with basal diet, at level of 100, 150, 200, 300, 400, and 800 mg/kg body weight of chicken, respectively. Among the experimental groups, birds in the T3 group represent the highest body weight. Furthermore, treatment group birds had shown better physio-biochemical indices as compared to control group birds. Interestingly, lower mortality rate due to ascites and coccidiosis was recorded in treatment groups and therefore, higher net return was observed. Hence, present investigation demonstrated the beneficial effect of H. rhamnoides extract (@200 mg/kg) at high altitude and therefore, may be used in formulation of feed additive for poultry ration.

Effect of hydro-alcoholic extract of Rhodiola imbricata on growth performance, immunomodulation, antioxidant level and blood biochemical parameters in broiler chickens at high altitude cold desert

Extremes of climate and hypobaric hypoxia cause poor growth performance in broiler chickens at high altitude.The current study was designed to investigate the effect of hydro-alcoholic extract of Rhodiola imbricata onantioxidant, cytokines, blood biochemical and growth performance of broilers at high altitude (3500 m). For invivostudy, one day-old broiler chicks of average initial body weight 36.40±0.42 g were randomly assigned to seven groups in three replicates (10 chicks in each replicate) as per completely randomized design. Experimental groups included control (fed basal diet), and treatment T1, T2, T3, T4, T5, and T6 which received hydro-alcoholic extract of Rhodiola imbricata in drinking water @ 100, 150, 200, 300, 400, and 800 mg/kg body weight of chicken respectively, along with basal diet. Blood samples were collected at 0, 21st, and 42nd day. HPLC analysis of extract revealed the presence of salidroside and p-tyrosol. As a result of this study, birds in T5 group had significantly higher body weight as compared to other groups. Furthermore, they had significantly higher total antioxidant capacity, free radical scavenging activity, interleukin-2, total protein, globulin, HDL level and lower malondialdehyde, interleukin-6, cholesterol, triglyceride, LDL, glucose, A/G, ALT, AST level as compared to control group. Our results suggest that, Rhodiola imbricata extract @ 400 mg/kg body weight of chicken, exhibited beneficial effect on growth performance and therefore, can be used as a phytogenic feed additive for broiler chickens.

Effect of Prunus armeniaca seed extract on health, survivability, antioxidant, blood biochemical and immune status of broiler chickens at high altitude cold desert

Extreme climatic conditions and hypobaric hypoxia at high altitude hinders the growth and productivity of chickens. The present study was carried out to examine the effect of aqueous extract of Prunus armeniaca seeds on health, survivability, antioxidants, plasma biochemical parameters, and immune status of broiler chickens at high altitude. Phytochemical analysis of extract revealed the presence of high phenolics, flavonoids, and carotenoids contents. Before the in vivo study, in vitro efficacy evaluation indicated a significant protective effect of the extract in chicken peripheral blood lymphocytes. For in vivo study, experimental groups include control (fed the basal diet), and treatment T1, T2, T3, T4, T5, and T6 which received an aqueous extract of P. armeniaca in drinking water at concentrations of 100, 150, 200, 300, 400, and 800 mg/kg body weight of chicken respectively, along with basal diet for 42 days. Body weight was significantly increased in all treatment groups as compared to control group and the highest body weight was recorded in T3 group. Higher profit was gained in treatment groups due to lesser mortality in chickens. Moreover, chicken in the treatment groups had significantly higher total antioxidant capacity, free radical scavenging activity, interleukin-2, total protein, albumin, globulin level and lower malondialdehyde, interleukin-6, glucose, cholesterol, triglyceride, ALT and AST level as compared to control group. Results suggest that, P. armeniaca extract at 200 mg/kg body weight of chicken, exhibited the beneficial effect on growth performance and survivability rate of broilers and therefore, could be useful as phytogenic feed additive for broiler chickens at high altitude cold desert.