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- First evaluation of the efficacy and operational cost of acaricidal bath
combining different droplet sizes, pressures and spray patterns in dairy
cows naturally infested with Rhipicephalus microplus
Abstract: Rhipicephalus microplus poses a significant challenge to animal health. This study evaluated efficacy and the effective operational cost (EOC) of different acaricidal treatments varying droplet size, pressure and spray pattern using a power sprayer. Three experiments were conducted on dairy cows, with each experiment involving three groups of 10 animals: two treated groups and one untreated control group. In the first experiment, acaricide treatments with the same droplet size (medium) were compared at different pressures (50 and 100 psi) using a full cone spray pattern: E1-M50 and E1-M100. In the second experiment, different droplet sizes (fine and medium) were compared at the same pressure (100 psi) using a full cone spray pattern: E2-F100 and E2-M100. The third experiment compared droplet sizes and spray patterns (fine at full cone and ultra coarse at flat fan) at the same pressure (100 psi): E3-F100 and E3-UC100. All animals received acaricide treatment on day 0 with a product based on organophosphate and pyrethroid. Tick counts were performed on days + 7, + 14, and + 21 to determine treatment effectiveness. Data on bath time were collected to determine the EOC, besides cost with acaricide, labor, water and electricity. No statistical differences (p > 0.05) regarding the mean tick count were observed between treated groups in all experiments. However, the highest efficacy values were found in treatments with larger droplets (medium and ultra coarse) and higher pressure (100 psi). In experiment 1, the efficacy varied from 70.6 to 88.9% and 75.2 to 93.7% for the treated groups E1-M50 and E1-M100, respectively. In experiment 2, efficacy varied from 48.7 to 86.2% for E2-F100 and from 68 to 94.7% for E2-M100. In experiment 3, efficacy ranged from 62.9 to 76.9% for E3-F100 and from 73.4 to 86.5% for E3-UC100. The EOC of the acaricide bath varied between 0.42 and 0.46 USD per animal. The findings show that treatment efficacy and EOC vary depending on the spray parameters used for the control of R. microplus, but further studies should be conducted to determine better combinations of pressure, droplet size and spray pattern.
PubDate: 2025-03-21
- Pre and post weaning performance of Columbia sheep under an intensive
system of the central Mexico: an alternative to enhance meat production
Abstract: The aim of this study was to evaluate the pre and post-weaning performance of Columbia lambs under an intensive system in central Mexico. Productive data of 657 Columbia lambs (346 males and 5.3 kg at birth; 311 Females and 4.9 kg at birth) in the period from 2017 to 2020 were considered. Live weight data were collected by sex, birth weight (BW), pre-weaning average daily gain (preADG) and post-weaning average daily gain (postADG), weaning weight (WW), final weight (FW), final age (FA) and mortality percentage data. No significant interactions between year, sex and litter size were found (p > 0.05). Differences were detected among years for all variables (p
PubDate: 2025-03-21
- Effect of heat stress on pig production and its mitigation strategies: a
review
Abstract: Heat stress (HS) poses a significant challenge to pig production worldwide, with far-reaching consequences for productivity, reproduction, and overall animal welfare. Stress, broadly defined as the nonspecific physiological response to environmental demands, disrupts homeostasis, leading to health imbalances, behavioral changes, and reduced productive efficiency. Pigs are particularly susceptible to HS due to their limited thermoregulatory capacity, influenced by a low density of functional sweat glands and a thick subcutaneous fat layer. Rising global temperatures have exacerbated HS-induced economic losses in the swine industry, manifesting as decreased growth rates, poor reproductive performance, reduced feed efficiency, increased morbidity, and mortality. HS impairs pig production by diminishing feed intake and nutrient availability, which leads to reduced growth, suboptimal carcass quality, and compromised reproduction. Sows experience increased anestrus, extended weaning-to-estrus intervals, and smaller litter sizes, while boars exhibit reduced semen quality and fertility. The genetic selection for higher productivity has inadvertently lowered heat tolerance, as metabolic heat production increases with improved production traits. Furthermore, inadequate environmental management in pig housing exacerbates the impact of HS. Variations in heat tolerance among pigs underscore the importance of understanding genetic, physiological, and environmental factors influencing their response to HS. Research reveals genetic differences in thermotolerance, offering potential avenues for selective breeding to improve resilience. Effective management strategies, including nutritional adjustments, environmental modifications, and genetic selection, are crucial for mitigating the negative effects of HS and enhancing pig productivity. This review highlights the multifaceted impacts of HS on swine production, explores the physiological and reproductive consequences, and discusses adaptive and ameliorative measures to address these challenges, with a focus on maintaining sustainable pig production in the face of climatic changes. Graphical Abstract
PubDate: 2025-03-21
- Effects of replacing barley grain with corn grain on performance, rumen
and blood parameters in dairy cows fed alfalfa hay or corn silage
Abstract: Different grain sources in the diet have shown varying effects on performance of dairy cows. Also, the variability in response to different starch sources is influenced by the type of forage used. This study investigates the combined effects of two forage (alfalfa hay vs. corn silage) and grain (barley vs. corn) sources on dry matter intake (DMI), feed efficiency, milk production and composition, apparent nutrient digestibility, blood metabolites, and ruminal metabolism of dairy cows. Eight second-parity early lactation Holstein cows (63 ± 5 d in milk) were used in a replicated 4 × 4 Latin square with a 2 × 2 factorial design. Diets were iso-energetic and iso-nitrogenous and were based on either corn (CG) or barley (BG) grains, and corn silage (CS) or alfalfa hay (AH). Diets with CS had more long (108 vs. 68 g/kg DM) and medium particles (369 vs. 331 g/kg DM), and thus, longer mean particle size (5.4 vs. 4.6 mm) compared to diets with AH. Cows fed BG had less DMI and lower actual and energy-corrected milk (ECM) yield than CG-fed cows. The total tract digestibility of starch (952 vs. 987 g/kg) and crude protein (CP) (687 vs. 743 g/kg) were lower in CG cows than cows fed BG. Additionally, cows fed CG tended to have lower ruminal propionate concentrations than those fed BG, suggesting differences in ruminal fermentability between BG and CG. Milk fat content (30.6 vs. 29.2 g/kg) and ECM production (42.6 vs. 40.7 kg/d) tended to be greater in cows fed diets containing AH rather than CS. Furthermore, despite similar nutrient digestibility and total volatile fatty acid production, AH-fed cows had a higher ruminal acetate-to-propionate ratio compared to those fed CS. Replacement of BG with CG improved performance by increasing DMI; however, the expected positive effects of substituting CS with AH in BG-based diets may be obscured by the impact of differences in forage particle size (PS). These results indicated that inclusion of CG might be an optimum choice for modulating ruminal condition and enhancing performance compared to BG during early lactation.
PubDate: 2025-03-20
- Identification of polymorphisms and genetic diversity studies of
interferon regulatory factor 3(IRF3) gene in Muturu,White Fulani and
N’Dama cattle
Abstract: Interferon regulatory factor 3 (IRF3) is one of the strongest positional candidate genes implicated in a host of health-related phenotypes such as general disease resistance. The study was carried out to genetically characterize IRF3 gene in, N’Dama, Muturu and White Fulani cattle. DNA was extracted from the blood samples using the Zymo-spin extraction kit. ARLEQUIN 2.0001 software was used to estimate the basic population genetic statistics while DnaSP version 5.10.01 was used to estimate genetic diversity indices and test for deviation from neutrality. A total of 18 and 29 Single nucleotide polymorphisms (SNPs) were observed using codon code aligner in exons 1–2 and 5–6 of the IRF3 gene respectively in the three cattle breeds after polymerase chain reaction and sequencing. In exons 1–2, the Muturu (MU) possessed the highest value of SNPs (16) and genetic diversity indices, while the N’Dama (ND) possessed the least (1). In exons 5–6, the highest value of SNPs (14) was observed in the White Fulani and the genetic diversity indices was also high while the Muturu had the least. Analysis of molecular variation (AMOVA) carried out for the loci under consideration revealed a higher level of variation among populations than within populations. It was therefore concluded that the IRF3 gene had many polymorphisms and was highly diversified in Nigerian cattle breeds.
PubDate: 2025-03-19
- Creatine kinase levels, carcass, and physicochemical properties of breast
meat from traditionally slaughtered village chickens
Abstract: The objective of the study was to determine the effect of sex, season, and breed on creatine kinase (CK) levels, carcass, and the physicochemical properties of village chickens slaughtered using the transverse neck incision (TNI). One hundred chickens were stratified based on sex, breed, and season and were randomly assigned to different treatment groups to assess their live weight, carcass weight, meat quality, and CK levels. Results indicated that sex influenced live and carcass weights, with cocks (P
PubDate: 2025-03-19
- Prevalence and treatment of camel mastitis in Afar, Ethiopia
Abstract: Subclinical mastitis is a significant health concern in lactating camels, impacting milk production and pastoral livelihoods. This cross-sectional study aimed to determine the prevalence of subclinical mastitis and document traditional treatment practices among pastoralists in the Afar region, Ethiopia. A total of 384 purposively selected lactating camels were screened using the California Mastitis Test (CMT), and structured interviews were conducted with camel owners. The overall prevalence of subclinical mastitis was 60.2% (231/384), with a quarter-level prevalence of 27.6%. The right hind quarter was the most affected (40.4%). Pastoralists identified various clinical signs of udder infection, locally known as Samoboda, including udder swelling, changes in milk color, teat wounds, and reduced appetite. Traditional treatment practices involved the use of medicinal plants (Moyayto, Abar-haba, and Mus-uurruga), as well as methods such as cleaning with soap and salt, smearing with Darrita (soil), burning, hot metal branding, and manual drainage of swellings. The high prevalence of subclinical mastitis highlights the need for targeted interventions, including improved milking hygiene, routine health screenings, and effective tick control programs to enhance camel health and productivity in pastoral systems.
PubDate: 2025-03-19
- Forecasting reproductive performance in Holstein heifers and cows in a hot
environment: a time-series analysis
Abstract: This study aimed to predict the pregnancy rate (PR) and number of services per pregnancy (SP) in a large high-input dairy herd in a prolonged high ambient temperature zone. Also, the impact of climatic conditions on reproductive performance was assessed. An autoregressive integrated moving average (ARIMA) model was used in data fitting to predict future monthly PR and SP using data from 2014 to 2020. The highest predicted PR for cows was in January (35.3%; 95% CI = 30.5–40.1), and the lowest was in August (12.5%; 95% CI = 7.5–17.6). Temperature-humidity index (THI) and PR were significantly negatively correlated in the same month (r = 0.7) and 2.5 months earlier and 2.5, 5, and 7.5 months later. The predicted highest SP for cows was in September (6.2; 95% CI = 4.8–7.7) and the lowest for March (2.8; 95% CI = 1.3–4.2). The predicted highest PR in heifers was in January (62.2%; CI = 51.6–72.9) and the lowest in May (52.3%; 37.9–66.7). The cross-correlation between THI and PR in heifers was not significantly correlated in the same month, but significantly negative correlations occurred 5, 7.5, and 10 months earlier. SP in heifers were related to seasonality, with the predicted maximum SP occurring in May (1.9; CI = 1.2–2.6) and the minimum in February (1.6; CI = 1.0–2.2). It was concluded that weather strongly influenced the monthly reproductive performance rhythms of Holstein cows and heifers. Also, ARIMA models robustly forecasted reproductive outcomes of dairy cows and heifers in a hot desert climate.
PubDate: 2025-03-19
- Unconventional plant sources as alternative feedstuffs in broiler rabbit
nutrition: a scoping review
Abstract: Rabbit meat production offers a sustainable solution to meet the rising demand for protein, particularly in regions abundant in plant biomass. This review explores the potential of forages (legumes and non-legumes), medicinal, herbal, and aquatic plants as alternative rabbit feed sources. These alternatives boost protein, fiber, and bioactive compound content, enhancing productive performance, gut health, immunity, and meat characteristics. Challenges such as nutritional variations due to geographic location, seasonal changes, and processing methods, alongside nutrient-hostile factors and high fiber content, must be addressed. Nonetheless, these plants can be integrated into rabbit diets at levels of up to 10% without compromising animal health, performance, or digestibility. The study emphasizes the feasibility of incorporating alternative forages into rabbit feed, improving resource efficiency and sustainability in rabbit meat production. Notably, research indicates comparable growth performance between rabbits fed unconventional plants and those on conventional diets. Aquatic plants and aromatic herbs emerge as promising alternatives, enhancing growth, nutrient utilization, and carcass characteristics in rabbits. Despite challenges, careful dietary formulation can mitigate risks associated with certain unconventional feedstuffs. This review provides insights into formulating balanced, sustainable rabbit diets, highlighting the need for further research to optimize inclusion levels and mitigate anti-nutritive substances. Exploring unconventional plants as viable alternatives holds promise for enhancing both animal welfare and economic efficiency in the rabbit farming industry.
PubDate: 2025-03-19
- Estimation and geographical mapping of enteric methane emission from large
ruminants under different production systems in Pakistan
Abstract: Methane (CH₄) emission estimation from large ruminants reared in different production systems in Pakistan shows that milk producing animals majorly receive forage-based diet that is high in cellulose fiber along with concentrates to meet the nutritional requirement. The variability in diet is linked with different production systems in which animals are reared. The objective of this study was to estimate enteric methane emission (EME) of large ruminants reared in different production systems in Pakistan using IPCC Tier 2 guidelines and statistical models separately for cattle and buffalo. For 90.8 million population of large ruminants, cumulative CH₄ emission was 126.49 CO₂-Eq. (13.86 Gg per day and 5058.9 Gg in 365 days). Cattle shared a percentage of 48.4% with 40.66 CO₂-eq from Punjab and 20.73 CO₂-eq form Sindh province while buffalo shared a percentage of 51.6% with 45.41 CO₂-eq from Punjab and19.69 CO₂-eq from Sindh province. The percent difference in CH₄ production is assumed to be due to a greater number of animals being shifted from rural production system to commercial production system (population) and type of feeding strategies being implemented on these production systems (nutrition). To give mitigation strategies for EME in Pakistan, an accurate large dataset of EME estimates from whole country specifically from smallholder subsistence is required.
PubDate: 2025-03-18
- Critical thresholds of BHBA and NEFA for subclinical ketosis and its
prevalence prediction in Indian mithun (Bos frontalis) cows demonstrated
by ROC analyses
Abstract: Indian mithun (Bos frontalis), a rare ruminant species, is exclusively found in northeastern hill region of India and reared under semi-intensive system. Subclinical ketosis (SCK) is caused by an imbalance between energy supply and the needs of cows during lactation. To date, SCK prevalence is not known in mithun and biomarkers for its prediction have not been standardized. The study aimed to establish critical thresholds for serum beta-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA) for diagnosis and prevalence prediction of SCK in early-lactation mithun cows. Thirty apparently healthy multiparous (second to sixth lactation) mithun cows (average body weight of 342 ± 45.5 kg) with confirmed pregnancy were selected from two semi-intensive farms. None of the early-lactation mithuns with average milk yield of 1.2 kg/day exhibited signs of any metabolic disease during monitoring period (1, 2, 4 weeks post-partum). Using receiver operating characteristic (ROC) curve analyses, the optimal cut-off point was selected to be ≥ 1.10 mmol/L for BHBA (80% sensitivity, 80% specificity, AUC = 0.9) and ≥ 0.26 mmol/L for NEFA (88.20% sensitivity, 72% specificity, AUC = 0.9). In accordance with cut-off points, mithuns were classified as having SCK and healthy. At 1, 2 and 4 weeks post-partum, 55%, 82% and 64% of the mithun cows had SCK, respectively. There was a significant positive correlation between BHBA and NEFA concentrations (r = 0.78). A rise in serum NEFA and SGOT activity with a concomitant decline in total cholesterol and triglycerides may predict the risk of liver dysfunction associated with SCK. This study is of value in addressing future research on the development of fresh mithun cow programs to prevent SCK and associated liver dysfunction in first 4 weeks post-partum.
PubDate: 2025-03-18
- Multivariate analysis of morphometric traits of Malkangiri pony – a
heritage germplasm of Odisha
Abstract: The present study aimed to identify significant morphometric traits in Malkangiri ponies of Odisha through principal component analysis. The data were collected randomly from 200 ponies aged more than five years and 13 morphometric traits alongwith three indices were recorded. The mean height at wither, height at croup, body length, chest girth, punch girth, height at forearm, height at hock, fetlock to coronet, chest width, neck circumference, poll to wither, wither to croup and croup to head of the tail were 126.7 ± 0.39, 122.6 ± 0.29, 107.9 ± 0.2, 122 ± 0.31, 118.6 ± 0.46, 32.15 ± 0.33, 29.12 ± 0.45, 11.61 ± 0.04, 24.43 ± 0.2, 60.4 ± 0.18, 57.4 ± 0.19, 67.54 ± 0.25 and 28.56 ± 0.13 cm, respectively. The mean values for three indices, i.e., body index, length index and body ratio, were 88.49, 85.29 and 1.03, respectively. Phenotypic correlations among most of the morphometric traits were positive and significant. The correlation coefficient ranges from 0.9 to a minimum of − 0.26. Principal component analysis with varimax rotation extracted three principal components, collectively explaining 70.41% of the total variance. The first principal component accounted for the largest proportion of variance (50.57%), characterized by high loadings on height at wither (0.963), body length (0.917), chest girth (0.930), height at forearm (0.930), height at hock (0.885) and height at croup (0.766). The second principal component explained 10.71% of the variance and displayed a high loading on the distance between the croup to head of tail (0.828). Moreover, the third principal component accounted for 9.134% of the variance, represented by the distance from poll to wither (0.787). High communalities for traits in the first principal component underscored their significance in characterizing Malkangiri ponies.
PubDate: 2025-03-18
- Factors affecting Nile crocodile (Crocodylus niloticus) leather
quality: a systematic review
Abstract: Leather from the Nile crocodile (Crocodylus niloticus) is highly valued in global markets due to its durability, distinct texture, and aesthetic appeal. Despite its economic importance, the crocodile industry faces substantial challenges in maintaining the leather quality due to a variety of influencing factors. This study systematically reviews the literature that investigated the genetic, environmental, and management factors that influence the leather quality of Nile crocodiles. A comprehensive search on Google Scholar, ResearchGate, PubMed, and ScienceDirect databases yielded twenty-four studies published between 1960 and 2023. The analysis shows that genetic diversity and selective breeding programs play an important role in improving skin quality by promoting desirable traits and disease resistance. Environmental factors such as water quality, temperature, and habitat conditions have a substantial impact on skin health, with poor water quality and extreme temperatures contributing to skin diseases and defects. Management practices in crocodile farms should emphasize ideal stocking densities, balanced diets, and regular health screenings, which are essential for minimizing stress, injuries, and infections that degrade leather quality. Comparative studies with other crocodilian species, such as saltwater crocodiles, caimans, and American alligators, revealed both similarities and differences in the factors that influence leather quality, providing useful insights for improving techniques across species. This review adds to the body of knowledge by integrating current studies and providing actionable recommendations for improving Nile crocodile leather quality through improved genetic, environmental, and management practices. Scarcity of studies on crocodile leather remain a challenge. However, future research are needed that will explore longitudinal studies and the establishment of advanced practices to promote sustainable crocodile farming and assure the improved leather quality and industry's profitability.
PubDate: 2025-03-18
- Introducing alternative nonlinear models to characterize growth curves in
goats
Abstract: By applying some alternative nonlinear functions (such as the sinusoidal, Canter, and Lomolino), this study aimed to introduce these functions in research on the weight development of goats using goat growth data from the literature and their comparison with some routinely used growth models such as Monomolecular, Bridges, Janoschek, Von Bertalanffy, Richards, Schumacher, Morgan, and weibull. During the fitting of nonlinear regression curves, model performance was evaluated and model behavior was examined. The data used in this study came from two published articles reporting (i) body weight records on 120 male Beetal goats recorded at monthly intervals from birth to one year of age, and (ii) body weight records of 50 male South African non-descript indigenous goats. The adjusted coefficient of determination, root mean square error, Akaike's information criterion, and Bayesian information criterion were used to evaluate each model's overall goodness-of-fit to different data profiles. The models typically provided a good fit to the data, as evidenced by the generally high adjusted coefficient of determination values for each model. The selected sinusoidal equation accurately describes the dynamics of goat growth. Among the most effective functions for describing age-related fluctuations in goat body weight was the sinusoidal equation, which was found when comparing growth functions using the fitting criteria. Overall, this study offers implications for advancing research on goat production systems and provides insightful information on the application of alternative nonlinear models, particularly the sinusoidal equation, in modeling goat growth.
PubDate: 2025-03-18
- Retinol and cholecalciferol affect buserelin-induced estrous in anestrous
mares
Abstract: In winter anestrous, prolonged melatonin secretion inhibits gonadotropin-releasing hormone (GnRH). However, synthetic GnRH analogues such as buserelin can stimulate follicular development. We aimed to investigate clinical relationship between retinol, cholecalciferol, and buserelin for inducing estrous in anestrous mares (Equus caballus). We used a total of twenty-one anestrous mares, randomly divided into three groups of seven animals. Group A received retinol, cholecalciferol, and buserelin; group B received buserelin; and group C was control. Groups A, B, and C had 71.42% (n = 5; 95% CI: 26.30%-96.56%), 28.57% (n = 2; 95% CI: 16.56%-73.70%), and 0% mares in estrous, respectively. A significantly greater number of group A mares exhibited estrous (P = 0.005) and higher ovarian follicular size (P = 0.001) compared to group C. Serum estrogen was significantly higher in group A compared to Group B (P = 0.03) and C mares (P = 0.001). In multiple correspondence analysis (MCA) factor map, treatment with retinol, cholecalciferol, and buserelin was clustered with estrous mares having serum estrogen levels > 40 pg/ml and follicular size > 30 mm. The variance explained by the first two dimensions of MCA was 87.83%. Supplementing with retinol and cholecalciferol improved the rate of buserelin-induced estrous in anestrous mares. Further research is necessary to determine underlying mechanisms.
PubDate: 2025-03-17
- Effect of additional intracervical prostaglandin administration on
cervical dilatation during incomplete cervical dilatation in uterine
torsion corrected buffaloes
Abstract: Present study investigated the efficacy of additional intracervical (IC) prostaglandin (PG; cloprostenol sodium-500 μg) administration in buffaloes experiencing incomplete cervical dilatation (ICD) after uterine torsion correction. Twenty-two buffaloes in first stage of labor with soft to partially lobulated external-os post-torsion correction, with mean age: 7.0 ± 0.54 years, parity: 3.6 ± 0.47 (no.) and gestation length: 311.5 ± 1.12 days, were randomly divided into two groups viz. IC-group (n = 14) and intramuscular (IM) group (n = 8). In addition to conventional induction protocol, IC-group received an additional IC injection of PG at the start of experiment, whereas IM-group received an extra IM dose of PG after either 24 h or when no cervical dilatation progress was noticed. Surprisingly, mean cervical dilatation in terms of external-os and internal-os diameter after 12 h was 2.05 times and 3.38 times, and after 24 h, 2.03 times and 3.33 times higher (P
PubDate: 2025-03-17
- Ruminal fermentation kinetics and in vitro gas production of
yeast-enriched agro-industrial by-products as alternatives to soybean meal
in ruminant diets
Abstract: This study aimed to evaluate the impact of replacing soybean meal with yeast-enriched acerola, pineapple, and orange agro-industrial residues on ruminal fermentation kinetics and in vitro gas production. Using a 3 × 5 factorial design in a completely randomized design with three replicates, the study tested three agro-industrial residues (acerola, orange, and pineapple) at five replacement levels (0, 25, 50, 75, and 100% on a dry matter basis). Cumulative gas production was measured over time and analyzed using the Gompertz model. Linear and quadratic polynomial contrasts were used to examine the responses of feeds to increasing addition levels of the residues. The inclusion of pineapple residue linearly increased total gas production (P = 0.038), while acerola residue resulted in a linear decrease (P = 0.004) and orange residue had no significant effect on gas production (P > 0.05). Orange residue linearly reduced the lag phase (P = 0.048), acerola showed a quadratic effect with an increase of up to 75% inclusion, followed by a decrease (P = 0.009), while pineapple had no significant effect on the lag phase (P > 0.05). Digestibility of organic matter increased with the inclusion of orange and pineapple residues (P
PubDate: 2025-03-17
- Effects of breed, diet and sex on expression of growth-related genes in
Nigerian goats
Abstract: This experiment was conducted to study the effects of breed, diet and sex on expression of growth-related genes in Nigerian goats. A total of 36 weaner goats of two breeds (West African dwarf, n = 18; 9 males + 9 females) and Red Sokoto goats, n = 18; 9 males + 9 females) of about 3–4 months of age were used for the experiment. A 2 × 3 × 2 factorial experiment comprising 2 breeds, 3 diets groups and 2 sexes in a Completely Randomized Design was used. The data for gene expression and their interaction effects were all analysed using Statistix Analytical software, file version 8.0. Results showed that breed, diet and breed × diet interaction had significant (P 0.05) effect on the level of IGF-1 expression in the tissue of goats but had significant (P
PubDate: 2025-03-15
- Random regression in comparison with finite-dimensional models for
estimation of genetic parameters for growth traits in goats
Abstract: The application of the random regression model in comparison with finite-dimensional models (univariate and multivariate animal models) for genetic parameter estimation of growth traits in goats was evaluated in this study. A total of 2888 body weight records from 875 animals, recorded from birth to yearling age were used. All models included direct additive genetic and maternal genetic effects as a random effect in addition to fixed effects. Random regression model (RRM) was fitted with different orders (1st – 3rd) of Legendre polynomials and accounted for both homogeneous and heterogeneous residual variance. The best-fitting RRM had a polynomial of three orders for both random effects. The direct heritability estimate obtained via RRM was moderate to high, while it varied from 0.00 ± 0.08 to 0.36 ± 0.10 in finite dimensional models. A lower standard error of heritability and genetic correlation estimates was observed with RRM compared to multivariate (MUV) and univariate (UNI) analysis. Likewise, high accuracy and reliability of breeding value estimates are obtained via RRM, whereas the accuracy for MUV and UNI animal models were moderate and low to moderate, respectively. Based on standard errors, accuracy, and reliability of estimates, RRM seems versatile for genetic evaluation of growth traits of goats. However, the MUV animal model is the best-fitting model, according to the information criteria values. Thus, for small and less frequently measured data set, multivariate animal model seems good. Further studies with large and frequently measured body weight data sets may help ensure random regression’s applicability and differentiate it from finite-dimensional models.
PubDate: 2025-03-15
- Inclusion of yeast and saccharides based-product to replace monensin in
the diet of confined steers: performance, rumen environment, metabolism,
animal health, and meat quality
Abstract: The present study aimed to evaluate a blend of yeast and saccharides based-product fed via diet to feedlot cattle on performance, health, meat quality, and rumen metabolism when compared to monensin. Twenty-four non-castrated crossbred male steers (Charolais x Nellore) were divided into control (n = 12), receiving the basal diet with monensin (215 mg/animal/day) and treatment (n = 12) receiving the basal diet with the blend of yeast and saccharides based-product (17.2 g/animal/day). Animals were weighed on days 1, 20, and 113, and on days 20, 70, and 113, blood and rumen fluid were collected, which was also used to determine the genera of bacteria present in the rumen and to quantify protozoa. Total feces were collected to determine apparent total tract digestibility from days 108 to 112 of the experiment. There was no treatment effect for weight gain, feed intake, or feed efficiency. There was a gain in the loin eye area in the control group (P = 0.05) and greater subcutaneous fat thickness in the loin and rump cap control group (P = 0.01). In the ruminal fluid, there was higher protozoa count in the treatment group on day 113 (P = 0.03) and a higher proportion of propionic acid in the treatment group on day 70 (P = 0.03). Total short-chain fatty acids were lower in steers in the treatment group. There was no treatment effect on the ruminal microbiota. There were lower counts of lymphocytes and granulocytes in the blood of steer in the treatment group (P
PubDate: 2025-03-15
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