Gastrointestinal parasites affect the health and productivity of guinea pigs. This study aimed to determine the frequency of gastrointestinal parasite infection among naturally dead guinea pig carcasses collected from family-commercial farms in two high-Andean communities in southern Peru, to explore associated risk factors, and to quantify the parasite burden. A total of 223 rectal samples obtained from guinea pig carcasses that had died naturally were analyzed by flotation and McMaster techniques. The study used convenience sampling of carcasses from farms with at least 200 animals. Therefore, the frequency of infection estimated in the examined carcasses should not be extrapolated to the living guinea pig population. The overall infection frequency was 80.27% (95% CI 75.05-85.49). Paraspidodera uncinata (53.81%), Eimeria spp (34.98%), Capillaria spp (24.66%), Trichuris spp (13.90%), and strongylid-type nematodes (4.48%) predominated. Among infected carcasses (n = 179), 49.16% had mono-infection, 38.55% had bi-infection, 11.17% had tri-infection, and 1.12% had four parasites. In univariate analyses, the stage increased the probability of P. uncinata (OR = 2.33, p = 0.036), the rainy season increased the odds of P. uncinata (OR = 1.75, p = 0.038), and Eimeria spp (OR = 3.09, p < 0.001), and the Ccuyo community showed higher odds for Eimeria spp infection than Mamuera (OR = 2.48, p = 0.002), whereas the adult stage was protective (OR = 0.16, p < 0.001). Parasite burden varied widely, with Eimeria spp reaching extreme values (≈ 1.06 × 10[7] OPG). These findings support strengthened surveillance and integrated parasite control in young guinea pigs and during rainy season in the evaluated farms, while highlighting the need for future multivariate analyses that account for clustering by farm and include live-animal populations.

This study investigated the effects of replacing soybean meal (SBM) with black soldier fly larvae meal (BSFL) on the performance, carcass yield, blood biochemistry, hematology, and organ histology of broiler chickens. A total of 250 one-day-old Ross chicks were randomly allocated into five dietary treatments, with 5 replicates of 10 birds each, according to the following experimental design: a control group fed a basal diet (T1), and four groups with dietary replacement of SBM by 25% BSFL (T2), 50% BSFL (T3), 75% BSFL (T4), and 100% BSFL (T5). All groups were maintained under identical management and environmental conditions. At the end of the 35-day experimental period, the broilers were slaughtered, dressed, and weighed. The results showed that the 25% substitution level (T2) gave the best results, significantly improving body weight, weight gain, and the feed conversion ratio (FCR) with normal feed intake. The 50% group (T3) maintained a stable carcass weight similar to the control but showed lower feed intake. In contrast, higher levels (75% and 100%) decreased growth performance and carcass quality due to the high chitin content in the insect exoskeleton. Blood profiles and liver enzymes (ALT and AST) remained normal in most groups, confirming that the diet was safe. However, the 100% group (T5) showed higher cholesterol and HDL levels, and a lower albumin-to-globulin (A/G) ratio. Tissue analysis revealed only mild, non-pathogenic immune responses in the liver and lymphoid organs. Furthermore, BSFL did not alter the cecal microbial balance, maintaining normal Lactobacillus spp. and coliform counts, and all groups remained Salmonella-free. In conclusion, these findings indicate that BSFL can safely replace up to 50% of dietary SBM without compromising broiler health, development, or physiological status. This establishes BSFL as a viable, sustainable alternative protein source capable of reducing reliance on traditional soybean meal in poultry production, provided inclusion rates are optimized to prevent nutritional imbalances at higher substitution levels.

The use of agro-industrial by-products in ruminant diets has increased as a strategy to improve the sustainability of livestock production systems. This study evaluated the biological feasibility of replacing soybean meal with dried distillers' grains with solubles (DDGS) at a practical dietary inclusion level in feedlot lamb diets. Twenty-four Santa Inês ewe lambs (27.08 ± 2.89 kg initial body weight) were assigned to a completely randomized design with two dietary treatments: a control diet without DDGS and a diet containing 6.27% DDGS (dry matter basis). The experimental period consisted of 21 days of dietary adaptation followed by 52 days of evaluation. Productive performance, feed intake, feed efficiency, in vivo carcass traits, parasitological indicators, hematological variables, and serum biochemical parameters were evaluated. Dietary inclusion of DDGS did not affect average daily gain, final body weight, body condition score, Longissimus muscle area, backfat thickness, dry matter intake, feed conversion ratio, or feed efficiency (p > 0.05). However, lambs fed the DDGS diet showed lower dry matter intake relative to body weight (p = 0.021). Parasitological indicators, including eggs per gram of feces, Famacha© score, and packed cell volume, were not affected by dietary treatment. Most hematological and serum biochemical variables were also unaffected. Lambs fed the DDGS diet exhibited lower leukocyte and neutrophil counts (p < 0.05), whereas serum urea concentration was higher (p = 0.035), likely reflecting the higher dietary crude protein content. Overall, replacing soybean meal with DDGS at a commercially relevant inclusion level maintained productive performance, carcass characteristics, and the evaluated hematological and serum biochemical indicators in feedlot lambs under intensive tropical production conditions.

The impact of preincubation time/ duration (PI) and incubation temperature (IT) on growth, carcass, and welfare characteristics of broiler chickens were examined in this study. Following storage, hatching eggs were subjected to two PI treatments (6 h and 9 h). The PI treatments were subsequently split into different incubation groups. Throughout incubation, one PI treatment was held at a standard temperature (SI, 37.5 °C) while the other group was subjected to 39 °C (TM) between embryonic days (ED) 5 and 17. As a result, the following four experimental treatments were developed: Treatment 1 (Six-hour preincubation + SI, 6-PISI), Treatment 2 (Nine-hour preincubation + SI, 9-PISI), Treatment 3 (Six-hour preincubation + TM, 6-PITM), and Treatment 4 (Nine-hour preincubation + TM, 9-PITM). The results indicated that at 35 DOA (d of age), the feed intake (FI) of the 9-PI broilers was higher (P < 0.05) than the FI of the 6-PI broilers. At 35d of age (DOA), the TM broilers had a higher body weight (BW) and carcass weight than the SI broilers (P < 0.05). The rectal temperature (RT) at 28 DOA was lower in 9-PI broilers; however, the total antioxidant status (TAS) was higher in 6-PI broilers at 35 DOA (P < 0.05). In addition, the SI broilers had an increased (P < 0.05) concentration of IGF-1 than TM broilers. The PI and TM treatments had no effect on corticosterone (CORT), OSI (Oxidative stress index), and TOS (Total oxidant status) (P > 0.05); however, the bone length (B-L) of the broilers from the SI treatment was higher than that of the broilers from the TM treatment (P < 0.05). Six-hour PI coupled with TM during embryogenesis improved growth performance and carcass traits (P ≤ 0.05) however, no adverse effects of the experimental treatments were observed in the measured welfare-related indicators.

This study evaluated the effects of different space allowances on the behaviour and coccidial load in intensively reared Sirohi goat kids. Seventy-two healthy Sirohi goat kids (approximately three months of age) with similar initial body weights were randomly allocated to four space allowance treatments: 0.8 m[2]/kid (T1), 0.9 m[2]/kid (T2), 0.7 m[2]/kid (T3), and 0.6 m[2]/kid (T4), with three replicate pens of six kids each. Daily behavioural observations were conducted over 90 days using scan sampling, and faecal samples were collected on Days 0, 30, 60, and 90 to measure coccidial oocyst counts (OPG). Results showed that space allowance significantly affected behavioural responses and coccidial burden (p < 0.05). Kids in lower space allowances (0.6 and 0.7 m[2]/kid) exhibited more feeding, standing, drinking, and agonistic behaviours, while resting, locomotor activity, self-grooming, and affiliative interactions decreased compared to those in higher allowances (0.8 and 0.9 m[2]/kid). Stereotypic and eliminative behaviours were not significantly affected (p > 0.05). Coccidial burden increased over the experimental period, being highest in kids at 0.6 m[2]/kid (T4) and lowest in those at 0.9 m[2]/kid (T2). These findings suggest that providing adequate space allowance can improve behavioural welfare and reduce coccidial burden in intensively reared Sirohi goat kids, highlighting the importance of appropriate housing management in intensive production systems.

Information about on-farm goat productivity patterns is crucial for building resilient production systems in marginalised communities. Goat flock dynamics, management practices and production constraints in selected smallholder farming systems of Zimbabwe were explored. A multistage sampling approach was adopted to recruit a total of 200 participants. The effect of environment on productive indices and constraints was analysed using the Mann-Whitney U test and either Ordinal or Nominal logistic regression, respectively, in IBM SPSS version 26. Results highlight the importance of goats to rural communities. On average, 10.01 ± 5.14 goats were maintained per capita and the largest proportion was found in hot-humid environments (p > 0.05). However, reproductive performance in terms of average gestation length (4. 47 ± 0.59 months), age at first service (11.20 ± 2.24 months) and kidding (15.67 ± 2.30 months) was poorer in semi-arid environments than in the hot-humid areas (p > 0.05). Moreover, optimum productivity is hampered by a multitude of factors, including selection of breeding animals mainly based on personal appraisal (Index = 0.120), dependence of animals primarily on natural forages for feed (Index = 0.213), sub-optimal housing conditions like irregular cleaning (Index = 0.123) and disease preponderance (Index = 0.129). Ailments were mainly controlled using ethnoveterinary medicines (Index = 0.103). Taken together, our results underline the crucial role of goats to rural livelihoods, which could be elevated even more through community-based capacity building on proper animal husbandry practices in terms of breeding, nutrition, health and housing management.

Early identification of animals with high growth potential is essential for enhancing efficiency and sustainability in goat breeding systems. This study developed a machine learning-based predictive framework to estimate six-month live weight (LW2) using early-life phenotypic and environmental data from 52,938 Hair goat records collected between 2011 and 2024. Five models-Linear Regression, Ridge Regression, Decision Tree, Random Forest, and XGBoost-were systematically compared within a robust pipeline incorporating Winsorization, group-based cross-validation, and hyperparameter optimization. XGBoost achieved the highest performance (R[2] = 0.842; MAE = 1.96 kg), reducing unexplained variance and prediction error by approximately 36% and 23%, respectively, compared to the linear baseline (R[2] = 0.753; MAE = 2.54 kg). The model demonstrated strong generalization capacity and a biologically consistent residual structure. Explainable artificial intelligence (XAI) analyses confirmed that weaning weight (LW1) is the primary predictor of LW2, serving as an integrated proxy for genetic potential and early developmental conditions. Notably, weaning age emerged as a nonlinear determinant of growth efficiency despite exhibiting a weak linear correlation, underscoring the advantage of tree-based ensembles in capturing maturation dynamics. A data-driven decision threshold (LW1 ≈ 21.7 kg), open to a plausible physiological interpretation, was identified, separating two groups with an approximate 9 kg difference in predicted weight. These findings demonstrate that routinely collected early-life data can be transformed into a reliable tool for early selection. The proposed Early Digital Selection framework facilitates proactive, data-driven breeding decisions at weaning, providing measurable improvements in prediction accuracy and resource allocation efficiency under heterogeneous field conditions.

Heat stress is a major constraint to sustainable poultry production in tropical regions. This study evaluated the effects of Lactobacillus plantarum 1582-fermented red onion bulb extract (LFRO), supplied through drinking water, on growth performance, cecal microbiota, and excreta gas emissions in heat-stressed yellow-feather chickens. A total of 300 one-day-old male Rilai chicks were assigned to four treatments in a completely randomized design with five replicate pens of 15 birds each: unsupplemented control or LFRO at 25, 50, or 100 mg/L in drinking water. Birds were reared for 70 days under natural chronic tropical heat stress, with the temperature-humidity index predominantly within the severe-to-very severe range (28.9-31.1). Supplementation with 100 mg/L LFRO increased final body weight and body weight gain, reduced feed intake, and improved feed conversion ratio over the whole trial. The European Production Efficiency Index and Broiler Performance Efficiency Factor were also highest in the 100 mg/L group. Cecal 16 S rRNA sequencing showed no major changes in alpha- or beta-diversity, but several selected bacterial genera were modulated. LFRO at 50 and 100 mg/L reduced ammonia emission from excreta, whereas the other measured gases were not affected. This study shows LFRO at 100 mg/L is a natural drinking water supplement that improves feed efficiency and gut microbial balance in yellow-feathered chickens exposed to chronic tropical heat stress.

This research assessed the impacts of high protein feeds on the performance of local rabbits under severe chronic heat stress (Temperature-Humidity Index (THI) = 31.47 ± 2). This research used 72 local rabbits aged 42 days of mixed sexes, which were distributed equally into three groups: low-protein (LP), medium-protein (MP) and high-protein (HP), receiving low, medium and high protein feeds containing 16.7%, 18.2% and 19.5% crude protein, respectively. Even though the rabbits were fed ad libitum, rabbits in HP and MP groups showed similar average daily gain and mean body weight, which were significantly higher than LP group by + 7.5% and + 6%, respectively. Feed conversion ratios were significantly lower in MP and HP rabbits than in the LP group, with reductions of 7% and 8%, respectively, reflecting better feed conversion efficiency in the former two groups. Compared to the LP group, both MP and HP groups showed similar improved slaughter weight (+ 7%), skin weight (+ 9%), and cold carcass weight (+ 8%), while showing different improved results for weight of kidneys (+ 6% and + 7%), weight of liver (+ 12% and + 15%), respectively. The LP group had a much higher Perirenal fat content (+ 42%, p < 0.0001) than the HP and MP groups, which showed similar results. Additionally, the height, width, and area of the villus in MP and HP rabbits were improved by 16-25%, indicating better nutrient absorption. The results of this study provide evidence that utilising dietary protein enrichment is beneficial in combating the adverse effects of weather-induced heat stress on the growth of local rabbits.

Understanding the environmental and management-related determinants of semen production is essential for optimizing artificial insemination programs in buffalo breeding. This study comprehensively evaluated the influence of major non-genetic factors and their interactions on semen quality and semen production traits in Mehsana buffalo bulls using one of the largest repeated-record field datasets reported for this breed. A total of 55,071 ejaculates collected from 244 bulls maintained at two organized semen stations in Gujarat, India, were analyzed. Semen volume, sperm concentration, initial sperm motility, post-thaw sperm motility, and the number of semen doses produced per ejaculate were evaluated using repeated-record linear mixed-effects models fitted by restricted maximum likelihood (REML), with bull included as a random effect and within-bull correlations modeled using a first-order autoregressive covariance structure. Age at semen collection, period of semen collection, and ejaculate number consistently influenced all semen traits, whereas farm and season exhibited trait-specific effects. Semen volume and semen dose yield generally increased with advancing age, peaked between 3 and 5 years (197-202 semen doses per ejaculate), and declined thereafter. The first ejaculate consistently produced greater semen volume, sperm concentration, and semen dose output than the second ejaculate (248 vs. 115 semen doses per ejaculate). Significant interactions among farm, age, season, and ejaculate number demonstrated that semen traits responded differently across management environments and physiological stages, supporting age-specific bull utilization and optimized semen collection schedules in organized breeding programmes. By integrating a large longitudinal dataset with repeated-record mixed-model analyses, this study provides a comprehensive characterization of non-genetic sources of variation affecting semen production traits in Mehsana buffalo bulls. The findings offer an evidence-based framework for optimizing bull utilization and semen collection strategies in organized breeding programs while highlighting the need for future investigations integrating fertility, physiological, environmental, and genomic information to elucidate the mechanisms underlying the observed associations.

Nutrition is a key determinant of performance, carcass traits, and production efficiency in beef cattle. In this context, feed additives have emerged as a promising strategy to enhance nutrient utilization and reduce production costs. We aimed to evaluate the effects of replacing urea with a product extruded urea enriched with essential oils (NFeed[®]) on nutrient intake, performance, blood parameters, and feed cost in feedlot-finished Nellore young bulls. Twenty-four non-castrated animals with an average initial body weight of 394.6 ± 53 kg were randomly assigned in a completely randomized design, following the treatments considering different combinations of NPN source in diet: 0% NFeed (100% of non-protein nitrogen from urea), 50% NFeed (50% of non-protein nitrogen from urea and 50% of non-protein nitrogen from NFeed), 75% NFeed (25% of non-protein nitrogen from urea and 75% of non-protein nitrogen from NFeed) and 100% NFeed (100% of non-protein nitrogen from NFeed). Final body weight, total weight gain, and average daily gain had a linear response, with the highest values in the 100% NFeed treatment. Feed efficiency and feed conversion exhibited linear effects, with the 100% NFeed diet resulting in the greatest feed efficiency and the lowest feed conversion. A quadratic effect was observed for plasma urea, and gamma-glutamyl transferase levels. The replacement of conventional urea with extruded urea enriched with essential oils (NFeed) represents a viable nutritional strategy for finishing beef cattle in feedlot systems. Increasing levels of NFeed linearly improved animal performance while maintaining similar feed intake, increasing feed efficiency reducing feed conversion, and the cost per kilogram of body weight gain. Thus, we recommend a partial replacement of urea by NFeed as a non-protein source in beef cattle feedlot.

This study investigated the epidemiological characteristics and associated risk factors of neonatal calf diarrhea (NCD) across 115 dairy cattle farms representing seven geographical regions in Türkiye. Our findings revealed a calf diarrhea prevalence of 26.81%, with an associated mortality rate of 15.58%. Furthermore, NCD was observed to cause a substantial 11-30% reduction in weight gain, highlighting its significant economic impact. Logistic regression analysis identified that the presence of dedicated maternity and calf housing, timely colostrum administration, and stringent hygiene protocols (specifically teat and bottle disinfection) significantly mitigate the risk of diarrhea. Notably, the probability of NCD was 81% lower in enterprises equipped with a maternity compartment and 71% lower in those with separate calf housing. While seasonal variations and regional climatic differences-specifically in temperate and Mediterranean zones-indicated a lower incidence of diarrhea, these parameters did not reach statistical significance. The study concludes that strategic investments in managerial infrastructure and the rigorous application of preventive hygiene practices are paramount to minimizing the substantial economic losses attributed to neonatal calf diarrhea in the dairy industry.

Babesiosis/theileriosis is a tick-borne disease caused by protozoan parasites of the genus Babesia and Theileria. Tick species of genera, such as Ixodes, Rhipicephalus, Haemaphysalis and Hyalomma, transmit these parasites. These diseases threaten livestock productivity and health, particularly in tropical and subtropical areas. These diseases have a significant economic impact due to reduced milk and meat production, reproductive losses, higher veterinary expenses, and, in extreme cases, animal mortality. Even after decades of research, piroplasmosis is still difficult to control and manage. The most common drugs to treat this disease include buparvaquone, diminazene aceturate, and imidocarb dipropionate. These drugs are known for toxicity, and recent reports of the emergence of resistance to these drugs are worrisome. Hence, the development of alternative sustainable control methods is necessary. This review examines the current status of research on plant-based natural extracts/compounds, with particular emphasis on combination therapies integrating natural products with synthetic antiparasitic agents.

Maintaining stable rumen function in mid-lactation dairy cows is essential for supporting metabolic efficiency and milk production. Sprouted barley (SB), due to its high digestibility and improved nutrient availability, has been proposed as a partial forage replacement in dairy diets; however, evidence regarding its effects in comparison with traditional forages such as alfalfa hay (ALF) remains limited. This study evaluated the impact of substituting 15% of dietary dry matter with SB on rumen fermentation characteristics, milk composition, and productive responses of mid- lactation Simmental cows. Thirty cows were assigned to either an ALF-based control diet or a diet containing SB for 90 days. Rumen fluid samples were collected on days 10, 45, and 90 to determine pH, total volatile fatty acids (VFA), and molar proportions of individual VFAs. Milk yield and composition, dry matter intake (DMI), and body condition score (BCS) were also monitored. SB inclusion did not affect DMI, BCS, milk yield, or milk composition, indicating that partial replacement of alfalfa hay did not limit intake or compromise metabolic status. Rumen pH was influenced by diet and time, with the ALF diet supporting greater pH stability, whereas the SB diet showed a gradual decline toward day 90. Total VFA concentration decreased over time in both groups without treatment effects, and changes in acetate, propionate, and butyrate were modest and within physiological ranges. Overall, supplementing sprouted barley produced minor shifts in rumen fermentation while maintaining normal physiological function and milk quality. These results suggest that sprouted barley is a safe and practical partial forage substitute in the diets of mid-lactation Simmental cows.