Asian Journal of Research in Animal and Veterinary Sciences

Comparative Evaluation of Productive and Reproductive Performances of Indigenous and Crossbred Buffaloes at Bagerhat Buffalo Breeding and Development Farm

2026-08-31T13:22:22+00:00

This study compared the growth, productive, and reproductive performance of Indigenous, Murrah x Indigenous, and Nili-Ravi x Indigenous buffaloes maintained at the Buffalo Breeding and Development Farm, Bagerhat, Bangladesh. A total of 300 farm records were evaluated for three genetic groups, with unequal numbers of animals among groups. Growth traits included birth weight, weight at six months, and adult body weight for both sexes; productive traits included daily milk yield, lactation milk yield, and lactation length; and reproductive traits included age at sexual maturity, age at first calving, calving interval, and services per conception. The available data were analysed using the t-test. Male adult body weight was highest in Murrah x Indigenous buffaloes (560.52±1.06 kg), followed by Nili-Ravi x Indigenous (503.86±1.11 kg) and Indigenous buffaloes (455.16±1.13 kg). The corresponding female adult body weights were 451.8±1.04, 409.22±1.08, and 355.92±0.95 kg, respectively. Daily milk yield was highest in Murrah x Indigenous buffaloes (2.66±0.06 litres). Lactation milk yield was 888.44±21.83 litres in Murrah x Indigenous, 878.2±17.25 litres in Nili-Ravi x Indigenous, and 784.44±28.33 litres in Indigenous buffaloes. Lactation length was greatest in Nili-Ravi x Indigenous buffaloes (351.06±7.31 days). Age at first calving and services per conception did not differ significantly among genetic groups. Overall, the crossbred groups showed higher growth and productive performance than Indigenous buffaloes, whereas reproductive performance was broadly comparable under the farm conditions studied.

Prevalence of Multidrug Resistant Phenotype in Escherichia coli Isolated from Swine Reared for Human Consumption in Abakaliki, South Eastern Nigeria

2026-09-03T11:26:08+00:00

Background: Escherichia coli is a commensal bacterium of the gastrointestinal tract of swine, but it can serve as a reservoir for antimicrobial resistance genes that pose significant public health risks through the food chain. This study assessed the prevalence, antimicrobial resistance profiles and multidrug resistance phenotypes of E. coli isolated from the nasal cavities of pigs reared for human consumption in Abakaliki, Nigeria.

Methods: A total of 200 nasal swab samples were collected from two intensive pig farms (OLUPA Pig Farm and ADCT Pig Farm) in Abakaliki, representing piglets, young/immature pigs and hogs/older pigs. Standard microbiological methods were used for isolation and identification. Antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion method, and the multiple antibiotic resistance index (MARI) was calculated.

Results: E. coli was isolated from 36 (18.0%) of the 200 samples, with isolation rates of 16 (8.0%) at OLUPA Pig Farm and 20 (10.0%) at ADCT Pig Farm, and there was no significant difference between farms (p = 0.414). Grower/finisher pigs had the highest isolation rate (52.8%), which was statistically significant compared with other age groups (p = 0.035). All isolates exhibited 100% resistance to colistin, cefoxitin, imipenem, ceftazidime, aztreonam, and cefotaxime. Tetracycline resistance showed significant farm-level variation (p < 0.001): it was observed in all isolates at OLUPA Farm (100%) but in only 50% of isolates at ADCT Farm. High susceptibility (100%) was observed for ciprofloxacin, gentamicin, and ofloxacin. MARI values ranged from 0.3 to 0.6, with an overall mean of approximately 0.45 and no significant difference between farms (p = 0.188). However, within OLUPA Farm, adult/breeding pigs exhibited significantly higher MAR indices than piglets (p = 0.020).

Conclusion: The nasal cavities of pigs harboured multidrug-resistant E. coli showing resistance to critically important antibiotics, including colistin and carbapenems. However, colistin resistance was assessed using disc diffusion, which is not the recommended method; confirmation by broth microdilution is required. These findings support the need for improved antimicrobial stewardship, routine surveillance and strict regulations on antibiotic use in pig production to reduce the public health risk posed by antibiotic-resistant E. coli from swine operations.

DNA-Based Analysis of PIT1 Gene Variation Among Chicken Strains in Akwa Ibom State, Nigeria

2026-09-04T04:46:53+00:00

The study aimed to identify and characterise PIT1 gene variation across three chicken strains in Nigeria using DNA-based analysis. Blood samples were collected from three chicken strains: Broiler, Normal-feathered, and Frizzle-feathered. Blood samples were initially collected from 20 birds per genotype (60 in total); of these, 5 samples per strain (15 in total) yielded successful DNA amplification and were used for downstream sequencing and genetic diversity analyses. Bioinformatic analysis was performed using the gene sequences. PIT1 gene sequences were aligned and analysed; the results revealed that the Frizzle-feathered and Broiler chicken populations were closely related, whereas the Normal-feathered chicken population was genetically distinct from the other chicken populations. Regression analysis showed complete D' in both Broilers and Frizzle-feathered chickens (D' = 1), but the reported r² value was lower in Broilers (0.6178) than in Frizzle-feathered chickens (1.0), indicating stronger allelic correlation in the Frizzle-feathered strain. Normal-feathered chickens showed the steepest negative LD-distance slopes, indicating more rapid LD decay within the fitted range; however, these regression slopes do not provide a direct estimate of recombination rate. Based on Table 1, Broilers showed the highest within-strain genetic diversity (H = 3, Hd = 1.0, NS = 3, K = 9.33, Pi = 0.0446), followed by Frizzle-feathered chickens (H = 2, Hd = 1.0, NS = 2, K = 3.33, Pi = 0.0145), whereas Normal-feathered chickens showed no detectable within-strain variation in the reported metrics (H = 0, Hd = 0.00, NS = 0, K = 0.00, Pi = 0.00). Moreover, the molecular marker (PIT1) used was highly polymorphic, informative, and suitable for the genetic characterisation of both Nigerian and exotic chicken populations. The marker results showed that Frizzle-feathered and Broiler chicken populations were closely related, whereas Normal-feathered chickens were genetically distant from Frizzle-feathered chickens. Normal-feathered chickens were genetically distinct from the other chicken populations in the phylogenetic analysis, but the study showed no detectable within-strain PIT1 diversity in the analysed Normal-feathered samples. The study revealed that the PIT1 gene, as a molecular marker, is useful for studying the evolutionary history and relationships among Normal-feathered, Frizzle-feathered, and Broiler chicken breeds and how evolutionary mutation has affected their genetic variation over time. Therefore, the PIT1 gene, as a molecular marker, should be used to study genetic variation and evolutionary relationships among chicken species, as it facilitates genetic improvement and conservation of chicken breeds.

Occurrence of ESBL-producing Escherichia coli and Methicillin-resistant Staphylococcus aureus at Selected Livestock-community Interfaces in Kandy, Sri Lanka

2026-09-07T11:56:50+00:00

Small-scale livestock farmers make a vital contribution to local milk, meat, and egg production in the Central Province. Although antimicrobial use is less common, these farmers use antimicrobials for therapeutic, metaphylactic, and prophylactic purposes. Certain communities have close and frequent contact with livestock and poultry, and locations with high-density human-animal contact are considered community, animal, and environmental hotspots. The objective of this pilot study was to assess the dissemination of antimicrobial resistance at the human-livestock-environment interface in selected livestock and community hotspots within the Kundasale and Wattegama Government Veterinary Ranges in Kandy District. Kumbukkadura (n = 55) and Ambakotte (n = 61) in the Kundasale Veterinary Range and Madawala (n = 25) in the Wattegama Veterinary Range were selected for the study. Samples (pharyngeal swabs, anal swabs, faeces, cloacal swabs, and other swabs) were collected from cattle, goats, poultry, squatting pans, and household waste outlets. Isolation and identification of E. coli and Staphylococcus aureus were performed using conventional methods. Antimicrobial susceptibility testing was performed and interpreted according to EUCAST criteria, and PCR assays for CTX-M and mecA were conducted using previously described methods.

CTX-M-carrying E. coli (n = 7) and methicillin-resistant Staphylococcus aureus (n = 11) were detected in the selected livestock-community hotspots. The findings indicate the presence of antimicrobial-resistant bacteria at the human-livestock interface and highlight the importance of appropriate hygiene measures, good animal husbandry practices, and biosecurity standards to reduce the potential dissemination of resistant microorganisms at the selected study sites. Additional veterinary supervision of these communities or hotspots is required to support measures aimed at reducing potential spillover of AMR determinants between animals and humans.

Dietary Influence of Scent Leaf (Ocimum sanctum) and Bitter Leaf (Vernonia amygdalina) Meals as Modulators of Oxidative Stress and Immune Response in Broiler Chickens

2026-09-17T11:35:03+00:00

Oxidative stress and altered immune responses can affect the health and productivity of intensively reared broiler chickens. This study evaluated dietary bitter leaf meal (BLM; Vernonia amygdalina), scent leaf meal (SLM; Ocimum sanctum), and their combination as phytogenic supplements affecting serum immune and antioxidant indices in broilers. Two hundred and fifty one-day-old unsexed Arbor Acres broiler chicks were randomly assigned to five dietary treatments, with five replicates of ten birds. The treatments comprised a vaccinated and medicated positive control, an unsupplemented negative control, 0.3% BLM, 2% SLM, and a combination of 0.3% BLM and 2% SLM. On day 21, serum samples were evaluated for cytokines, immunoglobulin A, total protein, oxidative stress markers, and antioxidant enzyme activities. Dietary treatment significantly affected interferon-gamma, interleukin-1β, interleukin-4, interleukin-10, catalase, glutathione peroxidase, and total protein. Birds receiving 2% SLM recorded the highest interferon-gamma (60.39 pg/mL), interleukin-4 (205.84 pg/mL), and interleukin-10 (25.64 pg/mL) concentrations. Immunoglobulin A did not differ significantly among treatments (P = 0.193), although the highest numerical value was recorded with 2% SLM. Total antioxidant capacity also did not differ significantly, but the combined 0.3% BLM and 2% SLM treatment produced the highest numerical value (13.37 mmol/L). These findings indicate that scent and bitter leaf meals influenced selected immune and antioxidant indices in broiler chickens under the conditions of this 21-day study.

Climate Change and Parasite Epidemiology: Impacts on Vector Distribution, Transmission Dynamics, and Disease Emergence

2026-09-17T11:15:06+00:00

Climate change is increasingly reshaping the epidemiology of parasitic and vector-borne diseases by altering the environmental conditions that govern vector distribution, parasite development, transmission seasonality, and host exposure. Rising temperatures, shifting rainfall, humidity, drought, flooding, vegetation change, and altered land use affect the survival, reproduction, activity, and establishment of arthropod vectors such as mosquitoes and ticks, expanding vector suitability into cooler temperate, highland, or higher-latitude regions while reducing transmission where heat or moisture becomes unfavourable. Climate change thus redistributes parasitic disease risk rather than uniformly increasing it. Transmission dynamics are further shaped by changes in vectorial capacity, extrinsic incubation period, seasonal activity, environmental survival of parasite stages, grazing patterns, reservoir-host distribution, and human-animal-environment contact. In livestock and wildlife systems, temperature and moisture influence free-living parasite stages on pasture and modify host exposure to infective stages. Climate change may also drive the emergence or re-emergence of parasitic diseases by creating newly suitable ecological niches for vectors, parasites, intermediate hosts, and reservoirs, although emergence rarely results from climate alone, depending instead on interactions with land use, animal movement, urbanisation, travel, trade, and surveillance capacity. This review synthesises key pathways linking climate change to parasite epidemiology, emphasizing vector distribution, transmission dynamics, and disease emergence, and argues for a One Health approach integrating climate-informed surveillance, preparedness, vector monitoring, and adaptive control strategies.

Localized Coagulative Myonecrosis Presenting as a Discrete Thigh Mass in a Captive Red Tegu (Salvator rufescens)

2026-08-31T13:18:12+00:00

A discrete, firm mass was identified on the dorsal aspect of the right thigh of an adult female Red Tegu (Salvator rufescens) maintained at Sardar Patel Zoological Park, Gujarat, India. The swelling had enlarged slowly over approximately four months, while the animal remained clinically stable with normal appetite, locomotion, and behaviour. There was no recorded history of trauma, intramuscular injection, or recent local treatment. Physical examination showed a well-circumscribed, non-fluctuant, non-painful mass approximately 3 cm in diameter, and radiography demonstrated a hyperdense lesion without orthopaedic involvement. Surgical excision was performed under isoflurane anaesthesia. Gross examination revealed a round, firm, well-demarcated intramuscular mass with a pale white-to-grey, dry, homogeneous cut surface. Microbiological analysis of a surgical-site swab showed no bacterial growth. Histopathological examination demonstrated a sharply demarcated focus of coagulative myonecrosis characterised by intensely eosinophilic, hyalinised myofibres, loss of cross-striations and nuclear detail, preservation of overall tissue architecture, and a thin fibrous capsule. Inflammatory infiltration was minimal, and no neoplastic proliferation, granulomatous reaction, parasitic structures, vascular thrombosis, or significant haemorrhage was identified. The surgical wound healed without complication, and no recurrence was observed during six months of follow-up. This case demonstrates that localised coagulative myonecrosis can present clinically as a discrete tumour-like muscular mass in a captive Red Tegu and supports histopathological examination for definitive lesion characterisation.

Therapeutic Management of Congenital Goiter in Goat Kid: A Case Report

2026-09-14T13:24:41+00:00

Congenital goitre was clinically suspected in a 15-day-old goat kid presented with progressive bilateral swelling in the thyroid region, gasping, difficulty suckling, reduced appetite, and a low haemoglobin concentration. According to the owner, the swelling had progressively increased since birth, and the clinical presentation was consistent with involvement of the thyroid region. Clinical examination recorded a respiratory rate of 50/min, rectal temperature of 103°F, and pulse rate of 85/min; blood examination showed haemoglobin of 9 g/dL. The diagnosis was based on nutritional history, clinical signs, and the anatomical location of the enlargement. Ultrasonography and thyroid hormone measurements were unavailable, limiting confirmatory assessment. The kid was managed with oral levothyroxine sodium and potassium iodide, together with meloxicam and haematinic support. Potassium iodide was administered daily for 20 days, and the clinical response was monitored during treatment. Complete regression of the swelling and clinical recovery was observed within 20 days. The case demonstrates a favourable short-term response to combined thyroid hormone and iodine supplementation in a clinically suspected case of congenital goitre. Nevertheless, the absence of ultrasonographic confirmation and thyroid hormone estimation requires cautious interpretation of the diagnosis and the presumed iodine-deficiency aetiology. Adequate mineral and iodine supplementation during pregnancy, together with avoidance of goitrogenic feeds, remains an important preventive consideration in goat management.