https://ijas.ut.ac.ir/ Iranian Journal of animal Science en daily 1 Wed, 23 Sep 2026 00:00:00 +0330 Wed, 23 Sep 2026 00:00:00 +0330 https://ijas.ut.ac.ir/article_108939.html The aim of this study was to investigate the effect of trehalose on semen quality of Ross-308 roosters during 24 hours of storage at 5°C. Semen samples were collected from 10 adult roosters and diluted with Ringer’s solution containing different concentrations of trehalose (0, 50, and 100 mM). The experiment was conducted in a completely randomized design with three treatments and four replicates. Semen quality was assessed at 0, 6, 12, and 24 hours of storage. Evaluated parameters included total and progressive motility, viability, plasma membrane integrity, and morphological abnormalities. Data were analyzed using SAS software. The results indicated that addition of 50 mM trehalose significantly improved sperm quality at all storage times compared with both the control and the 100 mM treatment. In this group, total and progressive motility, viability, and membrane integrity were increased, while morphological abnormalities were reduced. On the other hand, the use of a higher concentration of trehalose (100 mM) not only did not improve sperm quality parameters, but also showed a negative effect on certain indices, including sperm morphology. In conclusion, supplementation of rooster semen diluent with 50 mM trehalose exerts a protective effect and is recommended for short-term storage at low temperature (5 °C). However, higher concentrations are not advisable due to their detrimental impact on sperm quality. https://ijas.ut.ac.ir/article_108940.html This study aimed to evaluate the effects of combining pomegranate pomace as a natural source of tannins with black soldier fly larvae as an emerging protein source on rumen fermentation kinetics under in vitro conditions. The potential synergistic interaction between tannins and insect-derived protein in improving rumen fermentation efficiency was also examined. The research was conducted in two separate experiments using a completely randomized design. In the first experiment, different levels of the larvae–pomace mixture were assessed using the in vitro gas production technique, and parameters including pH, dry matter digestibility, protein digestibility, and ammonia nitrogen were measured at various incubation times. In the second experiment, the optimal level identified in the first experiment was selected as a protein supplement and compared with different replacement levels of soybean meal (0, 10, 20, and 30%).The results indicated that the combination of pomegranate pomace and black soldier fly larvae positively influenced rumen fermentation. In the first experiment, Treatment 6 improved dry matter digestibility(78/7) and reduced pH (6/51)and ammonia nitrogen(10/7). In the second experiment, Treatment 2 showed the highest gas production, favorable digestibility, and the lowest ammonia nitrogen concentration(6/40). Overall, this mixture can serve as a sustainable protein source and a suitable partial replacement for soybean meal in ruminant diets. Moderate levels of tannins enhanced fermentation and digestion, whereas higher levels exhibited inhibitory effects. These findings suggest that this innovative combination can improve protein utilization efficiency while contributing to the environmental sustainability of ruminant feeding systems. https://ijas.ut.ac.ir/article_108942.html This experiment was conducted to investigate the effect of different levels of commercial anti-stress additive on performance traits, carcass composition and blood parameters of broiler chickens. The experiment was carried out in a 2×4 factorial arrangement with 240 male Ross broiler chickens for 42 days. Treatments included: 1- control treatment, 2- treatment containing 1.5 g/kg anti-stress additive, 3- treatment containing 3 g/kg anti-stress additive, 4- treatment containing 5 g/kg anti-stress additive. Each of the treatments was in two environments with and without heat stress and with six replications. The results showed that the average daily weight gain, average live weight at the end of the period and production efficiency index in birds receiving different levels of anti-stress were higher than in the control treatment (P<0.05). Birds receiving anti-stress at levels of 1.5 and 5 g/kg had lower feed conversion ratio than in the control treatment (P<0.05). The average daily weight gain and the average live weight at the end of the period were significantly higher in the non-stressed environment (P<0.05). Treatments containing different levels of anti-stress additive had higher carcass weight than the control treatment (P<0.05). The hormone triiodothyronine in birds receiving different levels of anti-stress additive was significantly higher than the control treatment (P<0.05). Economically, the treatment containing 1.5 g/kg anti-stress additive accounted for a higher percentage of profit than other treatments. In general, supplementation with the anti stress additive at different levels improved growth performance indices and feed conversion ratio compared with the control treatment. https://ijas.ut.ac.ir/article_109101.html Twenty-four dry Holstein cows were used in a 2×2 factorial arrangement with four dietary treatments during the transition period (21 days before calving and 21 days after calving). The two factors were grain type (barley vs. corn) and the inclusion of a glucogenic additive. The treatments were as follows: 1) Barley-based diet without glucogenic additive, 2) Barley-based diet with glucogenic additive, 3) Corn-based diet without glucogenic additive, 4) Corn-based diet with glucogenic additive. The prepartum and postpartum diets differed in composition. Milk yield was not affected by dietary treatments, nor were milk composition parameters (protein and fat content). However, dry matter intake (DMI) postpartum tended to increase in cows fed the barley-based diet without the glucogenic additive. Nutrient digestibility (dry matter, organic matter, crude protein, non-fibrous carbohydrates, neutral detergent fiber, and fat) did not differ significantly among treatments. Similarly, ruminal parameters postpartum were not significantly influenced by dietary treatments, except for ruminal pH, which was lower in cows fed barley-based diets compared to those fed corn-based diets (p < 0.05). Ruminal ammonia nitrogen (NH₃-N) concentration was not affected by the treatments. https://ijas.ut.ac.ir/article_109029.html Mastitis is one of the most serious challenges confronting the dairy industry, yet gene regulatory mechanisms underlying the host response to Prototheca spp., which are emerging pathogens of mastitis, remain poorly understood. This study aimed to apply an integrative bioinformatics framework—including comparative transcriptome analysis, weighted gene co-expression network analysis, and bipartite regulatory network—to identify key co-expression modules with increased or decreased expression that are involved in gene regulatory mechanisms in the somatic milk cells of two groups of Holstein dairy cattle: mastitis-affected (n=8) and healthy (n=7). Genes exhibiting increased or decreased expression were analyzed separately (FC≥2and≤−2, FDR<0.05), and bipartite regulatory networks were reconstructed independently for each group. The upregulated hub co-expression module comprised 13 hub genes (POU2AF1, FCRL5, JCHAIN, CD19, MS4A1, CD79A, IL17A, IFNG, PAX5, CXCR5, TNFRSF13C, CD79B, and CD22) and two hub miRNAs (bta-miR-2404 and bta-miR-2887). These genes and miRNAs were predominantly associated with host defense mechanisms, immune system activation through inflammatory regulation, adaptive immunity, B- and T-cell responses, and the IL-17 signaling pathway. In contrast, the downregulated hub co-expression module consisted of six hub genes (CSN1S1, CSN1S2, CSN2, BTN1A1, LALBA, and PLIN2) and six hub miRNAs (bta-miR-2462, bta-miR-34a, bta-miR-1434, bta-miR-12001, bta-miR-11981, and bta-miR-1835). These elements were primarily involved in the regulation of milk synthesis and its components, physiological processes, and the glucagon signaling pathway. Overall, these findings provide a valuable foundation for identifying regulatory mechanisms associated with susceptibility or resistance to bovine mastitis caused by Prototheca spp., with potential applications in genetic improvement and breeding strategies. https://ijas.ut.ac.ir/article_109102.html Processing of lignocellulosic feeds with electron beam irradiation and fungal fermentation can improve fiber availability. This study examined the synergistic effects of electron beam irradiation and an Aspergillus oryzae liquid culture extract on wheat straw. Treatments included irradiation at 200, 300, or 400 kGy before (first set) or after (second set) fungal extract application. The chemical composition of the control treatment (unprocessed) and the six other treatments was determined according to standard methods, and the contents of neutral detergent fiber (NDF), acid detergent fiber (ADF) and indigestible NDF after 240 h of incubation (iNDF240) were measured using an ANKOM system and the filter bag technique. Gas production and ruminal degradability of dry matter and NDF were determined. A completely randomized design was used for statistical analysis, and data were analyzed using SAS 9.4. As irradiation dose increased, the contents of DM recovery, NDF, and ADF in all treatments decreased significantly compared to the control (P < 0.05), and this reduction was greater in the pre irradiated treatments. With increasing incubation time, cumulative gas production and ruminal degradability of DM and NDF increased markedly (P < 0.05). For all treatments, a very strong correlation was observed between gas production and ruminal degradability. Overall, the combination of 400 kGy electron beam irradiation prior to fungal processing showed the best performance, and its application could be a promising approach to improving the nutritional value of wheat straw. https://ijas.ut.ac.ir/article_109108.html Cryopreservation imposes physical and chemical stress on sperm, resulting in decreased motility, viability, and overall quality. This study aimed to investigate the effect of different concentrations of soy lecithin nanoliposomes (1, 2, and 3%) on the quality of sperm from Sarabi dogs after freezing-thawing. Sperm collection was performed manually from three Sarabi dogs using hand stimulation and a suitable collection device in the presence of a female dog in heat to stimulate sexual desire. The evaluation parameters included sperm motility, abnormalities (Hancock), sperm membrane integrity (eosin-nigrosin), acrosome membrane integrity (PSA), and membrane activity (HAST) after the freezing-thawing process. The results of this study showed that the extender containing 2% lecithin nanoliposomes exhibited higher total motility (65.5±1.8) compared to other nanoliposomal treatments, although this difference was not statistically significant compared to the control group (66.7±1.8) (P<0.05). The progressive motility results showed that the L2 group (55.5±1.5) was significantly higher than the other groups, although it did not differ significantly from the control treatment (52.3±1.5) (P<0.05). Similarly, the highest percentage of integrity, membrane activity, and acrosome integrity was related to the 2% lecithin nanoliposomes treatment, which did not differ significantly from the control treatment (P<0.05). Sperm abnormalities in this experiment were not significantly affected by the type of extender. Therefore, it seems that the use of the extender containing 2% lecithin Soy lecithin nanoliposomes can improve the properties of dog sperm after freeze-thaw. https://ijas.ut.ac.ir/article_109109.html This study aimed to evaluate the effect of different levels of alpha-lipoic acid (ALA) (1, 2, and 4 μM; AL1, AL2, and AL4, respectively) on the quality of ram sperm after freezing and thawing. Ejaculates were collected weekly from four adult rams using an artificial vagina for six weeks. Semen was mixed and diluted with egg yolk extenders containing 1, 2, and 4 μM ALA, as well as egg yolk extender without ALA (control group). Motility, viability, and membrane functionality of sperm were evaluated after freezing. The results of this paper showed that the AL4 group showed significantly higher total motility (69.2±2.3) than the other groups. Also, AL4 had higher progressive motility (46.6±3.7) than the other treatments. Compared with the control group, the AL4 group showed significantly higher plasma membrane integrity (72.6±1.9 vs. 51.4±1.9) and plasma membrane activity (75.2±1.3 vs. 52.4±3.1). AL4 showed the highest percentage of live sperm (68.2±2.5) and the lowest percentage of dead sperm (22.3±1.9) (P<0.05). Therefore, it seems that the addition of 4 μM to the egg yolk-based extender can increase the quality and viability of ram sperm after cryopreservation. https://ijas.ut.ac.ir/article_109179.html The present study was conducted to investigate the effects of using different levels of vitamins and trace minerals in diets on performance, immunity, hatchability, and vitamin and mineral adequacy indices in broiler breeders. For this purpose, 520 broiler breeders aged 50 weeks were used for 12 weeks in a completely randomized design with 13 treatments and 4 replications, and 10 breeders in each replication, and one rooster for every 10 hens. The experimental treatments included two dietary nutrient recommendation based on Ross 308 parent stock and 4th Brazilian tables for poultry, three levels of 100, 80, and 60 percent vitamins and trace minerals based on Ross recommendation, and two levels of 100, 80 vitamins and trace minerals based on Brazilian table recommendations'. Experimental treatments included T1(RM100, RV100), T2(RM80, RV100), T3(RM60, RV100), T4(RM100, RV80), T5(RM80, RV80), T6(RM60, RV80), T7(RM100, RV60), T8(RM80, RV60), T9(RM60, RV60), T10(BM100, BV100), T11(BM80, BV100), T12(BM100, BV80), T13(BM80, BV80). The results showed that the experimental diets had a significant effect on egg mass, egg production percentage, number of chicks per hen in 12 weeks and feed consumption per chick produced (P<0.05). Similarly, the results showed that the percentage of first-grade chicks, the percentage of second-grade chicks and the energy consumed to produce one chick were significantly affected by the experimental diets (P<0.05). The results also showed that the experimental diets had a significant effect on the immunoglobulin M titer (P<0.05). The effects of experimental diets on serum levels of glutathione peroxidase (GPX), alanine amino transferase (ALT), and alkaline phosphatase (ALP) as indicators of vitamin and mineral adequacy had a significant effect (P<0.05). Overall, the results of the present experiment showed that based on hatchability percentage, treatment 4 (RM100, RV80), based on energy consumption for production of each chick, treatment 5 (RM80, RV80), and based on immunity, treatment 6 (RM60, RV80) were the most suitable options. However, considering that the need for hatchability percentage covers most of the needs of broiler breeders, based on hatchability percentage, treatment 4 (RM100, RV80) is the best option for providing vitamin and mineral supplements for broiler breeders. https://ijas.ut.ac.ir/article_109200.html The use of agricultural by-products in livestock feed is a sustainable strategy to reduce feed costs and environmental impacts. This study evaluated the effects of multinutrient blocks containing molasses and vinasses on growth performance, blood metabolites, rumen parameters, and environmental sustainability in pregnant Mehraban ewes. Sixty ewes were divided to three groups: a control group grazing without supplementation, groups supplemented with molasse-based multi-nutrient blocks (MMNB) or vinasse-based multi-nutrient blocks (VMNB) at 300 g/day. Over a 30-day period, body weight, blood parameters, and rumen fermentation characteristics were assessed. The results indicated no significant effect of MMNB or VMNB supplementation on body weight (P > 0.05). However, blood glucose decreased on day 15 in the supplemented groups (P<0.05), suggesting improved insulin sensitivity, while urea levels increased (P < 0.05), likely due to higher nitrogen intake. Ruminal ammonia nitrogen levels were elevated in both the treatment groups, reflecting enhanced protein degradation. From an environmental perspective, MMNB and VMNB reduced the water footprint by 53% and 56%, carbon emissions by 50% and 53%, and land use by 63% and 66%, respectively, compared with conventional concentrate feed. The observed changes in blood metabolites, including improved antioxidant status, indicate enhanced resilience to metabolic stresses that are common in tropical environments, such as heat and poor forage availability. These findings highlight the potential of molasse- and vinasse-based feed supplements in improving livestock sustainability without compromising animal performance. By repurposing agro-industrial waste into nutrient-rich feed, this strategy addresses critical challenges in livestock production, reducing reliance on resource-intensive crops, curbing emissions, and promoting circular agriculture. Farmers and policymakers can adopt these blocks to enhance food system resilience amid climate change. https://ijas.ut.ac.ir/article_93063.html Bovine leukemia virus infection is more prevalent in dairy herds and so far there is no known cure or vaccine for this disease. This research aimed to conduct a genome-wide scanning (GWAS) study to identify genomic regions and candidate genes associated with BLV infection. This study was conducted using Iranian Holstein cows that were naturally infected with BLV. For this purpose, blood samples were collected from 150 Holstein cows in an industrial cattle farm in Isfahan, and DNA and serum were extracted from them. Then the prepared DNA samples were genotyped using k30 chips (SNPchip30k). Quality control of genotyped markers based on rare allele frequency indices (PMAF < 0.05), missing genotype (PMIND > 0.05), genotyping rate (PGENO > 0.05) and Hardy-Weinberg balance (PH-W <1×10-6) was performed by PLINK software. After the quality control analysis, 140 cows (77 patients and 68 controls) and 22868 markers remained for further analysis. After performing the genome scan analysis in the PLINK program, eight markers above the significance threshold were finally identified. Then, by bioinformatic analysis of significant genomic regions using online ensemble databases and genecards, genes associated with significant markers were identified, the most important of which include GRK4, TP53BP1, SCAPER, GLRB, PDGFC, TNIP2, PSTPIP1, CEP350, MR1, TOM1L2, SREBF1, COPS and TNFRS13B. Gene Ontology (GO) analysis showed that these genes are mostly involved in regulating enzyme activity, DNA stability, lipid activity, antiviral response, innate immune response, and disease resistance. https://ijas.ut.ac.ir/article_109028.html Domestication and selection pressures have left specific genomic footprints known as selective sweeps, reflecting livestock adaptation to specialized production goals and diverse environments. This study aimed to conduct a comprehensive high-resolution genome-wide scan to identify genomic regions distinguishing dairy-type from beef-type native Iranian cattle. Genomic information from 90 native Iranian cattle across eight breeds (Sarabi, Kurdi, Mazani, Taleshi, Sistani, Kermani, Najdi, and Farsi), genotyped using the Illumina BovineHD BeadChip, was analyzed. Animals were categorized into dairy type and beef/dual-purpose type groups. After quality control, 278,667 SNP markers were retained for final analysis. Selection signatures were detected using pairwise Fst comparisons with theta (θ) method and a 5-SNP sliding window (Win5) approach. The comparative genomic scan for selection sweep identified 23 significant genomic regions, with the highest concentration of signatures on chromosomes 12 (five regions), 8 (five regions), and 13 (four regions). Win5 FST values ranged from 0 to 0.21. Functional analysis revealed 29 candidate genes including PLIN2 (lipid metabolism), RIMS1 (fertility), SLC24A2 (stress response), and GLP2R (energy metabolism). The identified regions showed significant overlap with documented QTLs for muscle growth, fertility traits, and milk composition. The results showed that despite the absence of industrial breeding programs in Iran's traditional livestock systems, centuries of human and environmental selection pressures have left deep genomic footprints in the genome of Iranian native breeds.