Shahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Risk factors associated with stillbirth and dystocia in the Murciano-Granadina goat breed16495110.22103/jlst.2025.25466.1640ENMohammadMohseni TakaluDepartment of Animal Science, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, IranMasoodAsadi FoziDepartment of Animal Science, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, IranMortezaMokhtariDepartment of Animal Science, Faculty of Agriculture, University of Jiroft, Jiroft, IranJournal Article20250626Perinatal kid loss in the early and later stages of production is a major problem in goat breeding. This study investigates the associated risk factors of stillbirth and dystocia in the Murciano-Granadina goat breed under an intensive production system in the semi-arid tropical region of southern Iran. Data were collected from 2017 to 2024 on a private dairy farm in Ghale-Ganj city, the southern area of Kerman Province, Iran. Data included information from 8,349 kidding records across the first three parities. A multivariate logistic regression model was used to evaluate the influences of independent variables, including kidding year, kidding season, parity, birth type of kid born, sex of kid born, birth weight of kid born, gestation length of doe, and age of doe at kidding. The average incidence rates of stillbirth and dystocia across the first three parities were 2.73% and 3.90%, respectively. The obtained results revealed that stillbirth was significantly influenced by kidding year, sex of the kid born, gestation length of doe, and age of doe at kidding, whereas dystocia was significantly associated with kidding year and sex of the kid born. These findings can inform better management and breeding strategies to reduce perinatal losses and improve reproductive performance in Murciano-Granadina goats raised under intensive conditions.https://lst.uk.ac.ir/article_4951_06ef278774336f5e9aed89895186c0fa.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Using modelling to enhance zootechnical and economic performance in drylands goat meat production715495410.22103/jlst.2025.24775.1602ENJoão Paulo De FariasRamosFederal Rural University of Rio de Janeiro, Department of Animal Production, Institute of Zootechnic, BrazilWandrick Hauss DeSousaResearch, Rural Extension and Land Regulation Company of Paraíba, BrazilThiago De SousaMeloResearch, Rural Extension and Land Regulation Company of Paraíba, BrazilRodrigo Vasconcelos DeOliveiraFederal Rural University of Rio de Janeiro, Department of Animal Production, Institute of Zootechnic, BrazilFelipe QueirogaCartaxoFederal University of Paraíba, Center for Agricultural Sciences, Brazil0000-0002-2378-0420Flávio Gomes DeOliveiraResearch, Rural Extension and Land Regulation Company of Paraíba, BrazilLarissa Kellen Da CunhaMoraisResearch, Rural Extension and Land Regulation Company of Paraíba, BrazilThais Thatiane Dos SantosSouzaResearch, Rural Extension and Land Regulation Company of Paraíba, BrazilDanillo MartePereiraFederal University of Paraíba, Center for Agricultural Sciences, BrazilThamires Da CunhaLealFederal Rural University of Rio de Janeiro, Department of Animal Production, Institute of Zootechnics, BrazilJournal Article20250219This study aimed to develop a mathematical function for the performance of a goat production system for meat production, based on zootechnical and economic indicators. Data on the technical and economic parameters used in the models were obtained from the goat herd control file database, which covered the years 2013 to 2017. Descriptive statistics were performed using PROC UNIVARIATE, while multiple linear regression models were developed using PROC GLMSELECT. Multiple linear regression analysis showed an adjusted coefficient of determination, indicating that the variables mortality rate, calving interval, weaning rate, and reproductive efficiency explained 95 percent of the variations in total goat weight at weaning. The results indicated that total weight of offspring at birth and weaning, mortality rate, reproductive efficiency, and gross income affect the system's profitability and can be used as decision-making criteria in meat goat farming. Furthermore, feed costs and rainfall also influenced the predicted variables, highlighting the importance of integrating climatic and economic factors in herd management. The multiple linear regression equations developed in this study are a useful and accessible tool for ruminant technicians and producers, allowing simulations and analyses of different production and economic scenarios, contributing to strategic planning and the development of the meat goat production system.https://lst.uk.ac.ir/article_4954_4b3de37fc172a0e4b3fde6ae7b4d9d94.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Polymorphism of pyruvate carboxylase gene and its relation with productive and reproductive performance of dairy cows1723495610.22103/jlst.2025.25042.1616ENWaleedMohammedDepartment of Animal Production, College of Agriculture, Al-Qasim Green University, Al-Qasim, Babil, IraqHaithamHusseinDepartment of Animal Production, College of Agriculture, Al-Qasim Green University, Al-Qasim, Babil, IraqTahreerAl-ThuwainiDepartment of Animal Production, College of Agriculture, Al-Qasim Green University, Al-Qasim, Babil, IraqJournal Article20250401Genetic selection in dairy cattle can be enhanced by identifying the candidate genes and variants associated with economic traits. This study examined the productive and reproductive characteristics of Holstein cattle based on the genotypes of the pyruvate carboxylase (<em>PC</em>) gene. A total of 50 cows, aged three to five years, was included in the study, with identical feeding and maintenance protocols applied to all animals. All cows completed a lactation period of 305 days. The genotype and allele frequencies were determined through genotyping. Sequencing analysis of 816 bp amplicons detected two single-nucleotide polymorphisms (SNPs), rs42195003 and rs110476776. The association analysis of the two SNPs was not significantly associated with lactation period, dry period, milk composition<strong>, </strong>and reproductive performance (<em>P</em>>0.05). In contrast, the highest milk production (4305.63±222.01 kg), was associated with the CT genotype of the <em>PC</em> (rs110476776) polymorphism. The results revealed that the SNP rs110476776 in the <em>PC</em> gene was associated with total milk production in Holstein cows. This study may provide valuable insights into the role of the analyzed gene in the functional traits of dairy cattle; however, it is essential to validate the results by researching larger populations and different breeds of cattle.https://lst.uk.ac.ir/article_4956_ba00f6fd1171d731d1f8301a56df7a1e.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Monitoring changes in genetic parameters for growth traits over generations of selection in local chickens in Egypt2530499210.22103/jlst.2025.25494.1644ENEllhamAbbasDepartment of Animal Production, National Research Center, Giza, EgyptEssamEl-GendyDepartment of Animal Production, Faculty of Agriculture, Cairo University, Giza, EgyptAmaniYoussefDepartment of Animal Production, National Research Center, Giza, EgyptManalZaki El-DeenDepartment of Animal Production, National Research Center, Giza, EgyptShoukryEl-TantawyDepartment of Animal Production, Faculty of Agriculture, Cairo University, Giza, EgyptMarwaAhmedDepartment of Animal Production, National Research Center, Giza, EgyptMostafaHelalDepartment of Animal Production, Faculty of Agriculture, Cairo University, Giza, EgyptJournal Article20250702Estimating the genetic parameters for growth traits is a crucial step before designing breeding programs to enhance the productivity in local chicken breeds. The current study estimated the genetic parameters of two local chicken lines selected for meat production (Normally Feathered, CE1, and naked-neck, CE3) and tracked the changes in these parameters over three generations of selection. Heritability estimates for the hatch weight were moderate, ranging between 0.30 and 0.31. Lower estimates ranged from 0.28 to 0.33, and were obtained for BW2 and BW4, respectively. The genetic correlations were moderate to high, and varied from 0.43 (BW12 and BW18) to 0.88 (initial BW and BW2) in the seventh generation of selection. The values in the eighth generation had the same trend and varied from 0.41 (initial BW and BW18) to 0.86 (BW2 and BW4). Similar values were obtained for body weight gain (BWG) and growth rate (GR) traits, where the highest genetic correlation (0.86) was between BWG (0-6) and GR (0-6) in the seventh and ninth generations, respectively, and the lowest was 0.62 that found between BWG (6-12) and GR (12-18) in the eighth generation. However, the highest phenotypic correlation (0.71) was also obtained between BWG (0-6) and GR (0-6) in the eighth generation, and the lowest value (0.42) was obtained between BWG (6-12) and GR (12-18) in the ninth generation of selection. The results suggested that there is enough genetic variation for further improvement in body weight at the juvenile stage.https://lst.uk.ac.ir/article_4992_586514acae94abb29296ba6e57f3f8a2.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Effects of lysophospholipids on performance, blood lipid parameters, milk composition, and the expression of lipogenic genes in early lactating Holstein dairy cows3139501510.22103/jlst.2025.25503.1646ENMatinMovagharnezhadAnimal Nutrition, Faculty of Animal and Fishery Sciences, Sari University of Agriculture and Natural Resources, Sari, Mazandaran, IranYadollahChashnidelAnimal Nutrition, Faculty of Animal and Fishery Sciences, Sari University of Agriculture and Natural Resources, Sari, Mazandaran, IranAsadollahTeymouri YansariAnimal Nutrition, Faculty of Animal and Fishery Sciences, Sari University of Agriculture and Natural Resources, Sari, Mazandaran, IranMohsenGholizadehGenetics and Animal Breeding, Faculty of Animal and Fishery Sciences, Sari University of Agriculture and Natural Resources, Sari, Mazandaran, IranJournal Article20250704This study investigated the effects of lysophospholipid (LPL) supplementation at varying inclusion levels on blood parameters, milk production, milk fatty acid composition, and the expression of fat synthesis-related genes in Holstein dairy cows. A total of fifteen cows was randomly assigned to three dietary treatment groups: 1) a control diet with no LPL, 2) the control diet supplemented with 0.1% LPL based on dry matter, and 3) the control diet supplemented with 0.15% LPL based on dry matter. The experimental period consisted of a 14-day adaptation phase, followed by a 21-day data collection phase. The results indicated that the addition of LPL to the diet significantly enhanced the net lactation energy. Furthermore, blood lipid profiles improved with increasing LPL levels, suggesting enhanced lipid metabolism. The fatty acid composition of milk was significantly enriched in the 0.15% LPL group, particularly in terms of beneficial fatty acids. Moreover, the group receiving the higher LPL level showed upregulated expression of key lipogenic genes, including stearoyl-CoA desaturase (SCD) and fatty acid binding protein (FABP). Notably, daily feed intake and milk yield remained unaffected by LPL supplementation. Overall, the findings suggested that LPL inclusion, especially at 0.15% of dry matter, may improve metabolic efficiency and milk quality in early-lactation dairy cows. Further research is recommended to examine the long-term outcomes and economic benefits of LPL supplementation in dairy cows.https://lst.uk.ac.ir/article_5015_377c89533518e965fc2ee55d14c735a2.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Accuracy of non-linear kinetic models for predicting ruminal fermentation of agro-industrial by-products4148504710.22103/jlst.2025.25479.1642ENKhalilZaboliDepartment of Animal Science, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, IranSaeedMoradiDepartment of Animal Science, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, IranMostafaMaleckyDepartment of Animal Science, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, IranJournal Article20250630Gas production kinetics is considered as one of the key indicators for assessing the nutritional value of feeds; therefore, precise prediction of kinetic parameters can provide reliable estimates of the nutritive value of feedstuffs. The objective of this study was to assess the accuracy of various nonlinear models in predicting ruminal fermentation parameters using the <em>in vitro</em> gas production (IVGP) technique. The fermentation substrates used in this study were agro-industrial by-products, including sugar beet pulp, lemon pulp, tomato pomace, grape pomace, sesame meal, rapeseed meal, bakery waste, and saffron flower waste. Rumen fluid was collected from three adult ruminally-fistulated Mehraban rams, then filtered and buffered. Each of the feed samples (in 3 replicates and 3 separate runs) was incubated with buffered rumen fluid for 144 hours. The gas production data were fitted to five nonlinear models, including Exponential (EXP), Gompertz (GOM), Logistic (LOG), Mitscherling (MCH), and Weibull (WEB). The goodness of fit of these models was evaluated using metrics such as mean square error (MSE), coefficient of determination (R<sup>2</sup>), residual mean absolute deviation (RMAD), and mean percentage error (MPE). Additionally, the Akaike's information criterion (AIC), Bayesian information criterion (BIC), accuracy factor (AF), run test, and linear regression analysis were employed to assess the accuracy of the models. Based on MSE and R<sup>2</sup> statistics, the EXP model demonstrated the lowest accuracy (37.30 and 0.958, respectively), while the MCH (8.15 and 0.991, respectively) and WEB (4.02 and 0.996, respectively) models exhibited the highest accuracy (P<0.05). Additionally, the AIC, BIC, and AF statistics were lowest for the WEB and MCH models, and highest for the EXP model. The results of the run test and linear regression analysis corroborated these findings. Overall, these findings indicated that the WEB model was the most accurate among the evaluated models for predicting the rumen fermentation kinetics, offering a reliable estimate of the nutritional value of new feedstuffs, such as agro-industrial by-products.https://lst.uk.ac.ir/article_5047_e5538ede7e5ca3c6d3445ab41f062d12.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201The effect of fennel (Foeniculum vulgare) on MYOD1 gene expression in the muscle tissues of the thigh, shoulder, and loin in Kermani lambs4956504810.22103/jlst.2025.25689.1658ENNarjisAlhasoonDepartment of Animal Science, Faculty of Agriculture, Yasouj University, Yasouj, IranMohammad RezaBahreini BehzadiDepartment of Animal Science, Faculty of Agriculture, Yasouj University, Yasouj, IranMohammadrezaMohammadabadiDepartment of Animal Science, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, IranJournal Article20250812Medicinal plants have gained attention as natural alternatives to antibiotic growth promoters in livestock nutrition due to their bioactive compounds. Among these, fennel (<em>Foeniculum vulgare</em>) shows promise, though its role in muscle development remains underexplored. The MYOD1 gene, a key member of the myogenic regulatory factors (MRFs) family, regulates muscle cell differentiation and growth. Increased expression of this gene is associated with enhanced muscle performance. This study examined the impact of fennel supplementation on MYOD1 gene expression in selected muscle tissues. A total of 48 muscle samples were collected from 16 lambs, with 8 animals assigned to each of two experimental groups. From each lamb, three muscle types (shoulder, thigh, and loin) were sampled, resulting in 24 samples per group. Fennel supplementation significantly increased MYOD1 expression in all muscle types (P<0.05), with the highest expression in thigh and the lowest one in shoulder tissue. The results suggested that fennel may positively influence muscle development at the molecular level by upregulating the MYOD1 gene expression although its potential as a natural feed additive to support muscle growth and meat quality in livestock warrants further investigation. Given the MYOD1’s central role in muscle growth regulation, exploring how medicinal plants affect its expression could advance functional livestock nutrition and genetic improvement strategies. Future studies should examine the underlying molecular mechanisms and interactions with other growth-related genes.<br /><strong>Keywords:</strong> functional nutrition, fennel, muscle development, MYOD1 gene, medicinal plantshttps://lst.uk.ac.ir/article_5048_e43e90231fa97fa6a75e200e28dd6eae.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Effects of different copper supplement sources on growth performance, nutrient digestibility, and blood parameters in Holstein suckling calves5765505510.22103/jlst.2025.25468.1641ENYadollahChashnidelDepartment of Animal Nutrition, Faculty of Animal Sciences and Fisheries, Sari University of Agricultural Sciences and Natural Resources, Sari, IranRadmanBakhtiariDepartment of Animal Nutrition, Faculty of Animal Sciences and Fisheries, Sari University of Agricultural Sciences and Natural Resources, Sari, IranHamid RezaMardaniDepartment of Chemistry, Payame Noor University (PNU), PO BOX 19395‑3697 Tehran, IranJournal Article20250626To evaluate the effects of copper (Cu) supplement source on Holstein suckling calves, 40 newborn male calves (mean birth weight: 39.6±2.4 kg) were randomly assigned to a completely randomized design for 70 days. The four experimental treatments consisted of the basal diet (7.89 mg Cu/kg dry matter) supplemented with 10 mg Cu/kg dry matter from different copper sources: Cu-acetate (27% purity), Cu-chloride (36% purity), Cu-sulfate (23% purity), and Cu-tribasic (58% purity). Calf body weight (BW) was measured weekly, while starter intake was recorded daily. Apparent digestibility was assessed using acid-insoluble ash as an internal marker. Blood samples were drawn from the jugular vein at the end of the trial. Final BW, total weight gain, and average daily gain were significantly greater in calves fed Cu-acetate and Cu-sulfate compared to those receiving Cu-chloride and Cu-tribasic (P<0.01). Dry matter digestibility was significantly enhanced in calves fed Cu-acetate compared to the other experimental treatments (P<0.01). Apparent digestibility of ether extract (P<0.01) and acid detergent fiber (P<0.05) was greater in calves fed Cu-acetate than in those fed Cu-chloride or Cu-tribasic. Plasma globulin concentration was significantly greater in calves fed Cu-tribasic compared to those receiving Cu-acetate and Cu-chloride (P<0.05). Plasma cholesterol levels were significantly higher in the Cu-sulfate group than in the other treatments (P<0.05). The concentration of low-density lipoprotein was significantly lower in the Cu-acetate group compared to other treatments (P<0.05). Plasma zinc levels were significantly increased in calves receiving Cu-chloride compared to other groups (P<0.01). Plasma aspartate aminotransferase activity was significantly greater in calves fed Cu-acetate compared to those receiving Cu-chloride or Cu-tribasic (P<0.01). It was concluded that adding 10 mg Cu/kg dry matter to the basal diet through Cu-acetate and Cu-sulfate supplements had a more favorable effect on the growth performance in Holstein suckling calves compared to Cu-chloride and Cu-tribasic salts.https://lst.uk.ac.ir/article_5055_069cf420e523a7f3a547bbea13929ce4.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201Technical Note: In vitro evaluation of the slow-release properties of two commercial hindgut buffers for equines6772507710.22103/jlst.2025.25517.1647ENFoadHosseinzadehDepartment of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, IranSeyed HadiEbrahimiDepartment of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, IranAbdol MansourTahmasbiDepartment of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, IranVahideh HeidarianMiriScience and Technology Park, Ferdowsi University of Mashhad, Mashhad, IranAmin DarziLemraskiScience and Technology Park, Ferdowsi University of Mashhad, Mashhad, IranJournal Article20250724This study aimed to quantitatively evaluate the acid resistance and slow-release properties of two commercial lipid-coated sodium bicarbonate buffers (buffer I and II) designed for equine hindgut supplementation using validated <em>in vitro</em> models. The ability of buffers to resist reacting with acid was evaluated by measuring the gas produced from the incubation of buffers with an acid. Furthermore, the disappearance of the fat coat and the release of sodium bicarbonate were assessed using an <em>in vitro</em> enzymatic digestion method to simulate small intestine digestibility. The results showed that gas production from buffers I and II followed a linear manner. After 30 minutes of incubation in acid, gas production was approximately 16% of that observed in the uncoated. The lipid coating of buffer II was digested to a significantly greater extent than that of buffer I (P<0.001). This consequently led to a significantly greater release of sodium bicarbonate from buffer II (P<0.001). Accordingly, the final buffering capacity of the digesta was significantly higher in the bottle containing buffer II compared to the bottle containing buffer I (P<0.001). <em>In vivo</em> studies involving animals challenged with hindgut acidosis demonstrate the efficacy of equine buffers in supporting gut health.https://lst.uk.ac.ir/article_5077_2eb0d875ab68b2d0f5ada5a2fcdf40ce.pdfShahid Bahonar University of Kerman and Iranian Society of Animal ScienceJournal of Livestock Science and Technologies2322-355314220260201From rumen fermentation to productivity: a bibliometric synthesis of nanotechnology in small ruminant nutrition7388517410.22103/jlst.2025.26067.1683ENEliasIbrahimi Khoram AbadiDepartment of Animal Sciences, Faculty of Agriculture and Animal Science, University of Torbat-e Jam, Torbat-e Jam, IranJournal Article20251015Conventional dietary supplements in livestock often face challenges of poor bioavailability and environmental impact, limiting their sustainable use. Nanotechnology-based approaches present innovative solutions by improving nutrient efficiency and enhancing productivity in small ruminant. The present investigation offers a rigorous bibliometric examination of the worldwide scholarly discourse surrounding nanoparticle-mediated nutritional interventions in small ruminant species, particularly sheep and goats.<strong> </strong>Leveraging a structured analytic framework, this study scrutinized publication data amassed between 2010 and 2025 from the databases Science Direct, Google Scholar, and Dimensions. Data curation and refinement, performed via Publish or Perish and standardized into CSV format, enabled a robust keyword co-occurrence analysis using VOSviewer, thereby ensuring methodological rigor and reproducibility, with acknowledgment that results may be shaped by database scope, English-language bias, and keyword-selection thresholds inherent to co-occurrence mapping. Findings disclose an appreciable escalation in the volume of pertinent literature since 2017, with discernible spikes in scientific productivity concentrated in 2021 and 2023. The bibliometric mapping identified pivotal thematic nodes, namely nanotechnology, nanoparticles, livestock, sheep, digestibility, and bioavailability. Concurrently, emerging research frontiers such as selenium and zinc nanoparticles, rumen physiology, heat stress responses, toxicity, and nano-enabled drug delivery have gained greater visibility in recent scholarly output. Temporal analyses of keyword co-occurrence patterns demonstrated a field-wide evolution, transitioning from foundational inquiries into ruminal fermentation and in vitro digestibility toward sophisticated applications aimed at enhancing feed efficiency, safety, and overall efficacy. Notably, highly cited studies have consistently highlighted the superior bioavailability of nano-form selenium and zinc, which may serve as benchmarks for innovation in the domain. Parallel to these advancements, there is increasing scholarly attention on the assessment of biological safety, metabolic fate, and the ecological ramifications of nanoparticle use in animal nutrition. In summary, emerging evidence highlights that low-dose nano-selenium and nano-zinc can improve rumen function, antioxidant status, and growth in small ruminant, while reducing mineral excretion, when implemented through extension-guided dosing, verified suppliers, and phased farm-scale trials providing practical guidance for farmers and feed producers.https://lst.uk.ac.ir/article_5174_cdee67931bf4807a0ad61587274056d9.pdf