BMC Veterinary Research最新文献

Background: Staphylococcus aureus, a common cause of foodborne illnesses, may be transmitted from cows to humans through contaminated raw milk. Limited data exist on livestock-associated Staphylococcus aureus (LA-S. aureus) infections in Tanzania's bovine supply chain. This study assessed the prevalence and antibiogram of Staphylococcus aureus in cows' raw milk, from small-scale farmers in Magu district, Mwanza, Tanzania.

Methods: A cross-sectional study was conducted between April 2023 and June 2024. A total of 410 non-repetitive raw milk samples were collected from cows of small-scale farmers. Milk samples were processed to isolate Staphylococcus aureus as per laboratory standard procedures. Drug susceptibility was established with the Kirby-Bauer disk diffusion method following the Clinical and Laboratory Standards Institute (CLSI) guidelines, 2022. R software was used to analyze percentages and proportions of the data for all variables.

Results: The prevalence of Staphylococcus aureus in raw milk from small-scale farmers was 23.9% (98/410), with 16.3% (16/98) being methicillin-resistant Staphylococcus aureus (MRSA). The resistance proportions were penicillin 45.9% (45/98), tetracycline 33.7% (33/98), erythromycin 21.4% (21/98), cefoxitin 16.3% (16/98), clindamycin 6.1% (6/98), trimethoprim-sulfamethoxazole 6.1% (6/98), gentamicin 3.1% (3/98), and ciprofloxacin 1.0% (1/98). Of the 98 Staphylococcus aureus isolates, 20 (20.4%) were multidrug resistant (MDR) defined as resistance to three or more antibiotics.

Conclusion: The prevalence of Staphylococcus aureus was high with a significant proportion of isolates being MRSA, in raw milk from small-scale farmers. High proportions of antibiotic resistance and MDR patterns underscore the urgent need for improved antimicrobial stewardship and the promotion of responsible antibiotic use in dairy farming.

The irrational use of antibiotics in veterinary practice can cause growth impairment and decrease production performance in young animals. In this study, the distinctive properties of cecropin AD (CAD), including its pathogen-killing and beneficial bacteria-promoting abilities, were used to enhance the growth of underdeveloped lambs. Fifty-four Hu sheep (female, 5 months, 19.78 ± 1.45 kg) were randomly assigned to three dietary treatments for 5 weeks: N-CON (basal diet), L-AMPs (basal diet + 0.05 g CAD/sheep/day), and H-AMPs (basal diet + 0.1 g CAD/sheep/day). Dry matter intake (DMI) was recorded daily. At the end, three sheep per group were slaughtered to analyze gut microbiota, morphology, and blood biochemistry. Results showed CAD improved daily gain and feed-to-gain ratio in impaired sheep. It enhanced liver (GLO, ALT, AST, GGT, ALP; p < 0.03) and kidney function (BUN, CRE; p < 0.02), and significantly increased rumen papillae width/height (p < 0.01), duodenal villi height (p < 0.05), and the villus-to-crypt ratio (p < 0.01). It also upregulated tight junction proteins (ZO-1, Occludin, Claudin-1) in the rumen wall (p < 0.05) and duodenal epithelium (p < 0.05). In addition, CAD enhanced the diversity (Shannon, F = 6.89, p = 0.001) and abundance (Chao1, F = 8.32, p = 0.002) of beneficial carbohydrate-fermenting bacteria (e.g., s_Rikenellaceae-RC9_gut_group_unclassified, g_Prevotella, o_Oscillospirales, g_ruminococcaceae_nk4a214_group, and g_Christensenellaceae_R-7_group), while inhibiting non-fermenting (g_Succiniclasticum) and opportunistic pathogens (c_Negativicutes, o_Veillonellales, and f_Veillonellaceae). Consequently, in impaired sheep, CAD improved gastrointestinal tissue structure and barrier function, increased beneficial rumen flora, and thereby enhanced growth performance.

Background: Trichinellosis, a globally distributed zoonosis, threatens both human health and livestock productivity. The limited efficacy of existing anthelmintics underscores the need for innovative strategies to control Trichinella spiralis infection.

Results: A recombinant food-grade Lactococcus lactis strain (NZ-Bcl2) was engineered to secrete the anti-apoptotic protein Bcl2 by fusing the Bcl2 gene to the Usp45 signal peptide. Western blotting confirmed successful expression and secretion. NZ-Bcl2 strains exhibited stable growth, maintained plasmid inheritance over 24 generations without antibiotic pressure, and persisted in the murine intestine for at least seven days. In low-dose infections (150 larvae/mouse), oral administration of NZ-Bcl2 significantly reduced muscle larval burden, mitigated intestinal damage, and alleviated mesenteric lymph node enlargement. These protective effects were associated with downregulation of pro-inflammatory cytokines (IL-1β, TNF-α), upregulation of anti-inflammatory cytokines (IL-10, TGF-β), and increased expression of intestinal barrier markers (claudin-3, MUC-1). Under high-dose challenge (600 larvae/mouse), the protective effects were attenuated.

Conclusion: Recombinant L. lactis secreting Bcl2 confers partial protection against T. spiralis by enhancing mucosal barrier function and modulating host immunity. These findings highlight the potential of engineered probiotics as a novel platform for antiparasitic intervention, offering translational relevance for food safety and zoonotic disease control.

Background: Traditional medicine continues to serve as a primary source of healthcare for livestock in Ethiopia. However, ethnoveterinary practices are increasingly at risk due to cultural changes, habitat destruction, deforestation, and the overexploitation of medicinal plants. Documenting this traditional knowledge is essential for both drug discovery and the sustainable management of these resources. To address this, a cross-sectional study was conducted using semi-structured questionnaires by selecting 325 across five Kebeles to document the medicinal plants used in the treatment of livestock ailments in the Bure district.

Result: A total of 33 plant species, belonging to 18 families that are used to treat 20 different livestock diseases were documented. The most frequently reported families were Asteraceae (18.2%), Solanaceae (12.1%), Fabaceae (9.1%), and Acanthaceae (6.1%). Shrubs accounted for the largest proportion of growth forms (42.4%), followed by herbs (30.3%). Leaves were the most commonly used plant part (57.7%), followed by fruits (11.4%). The majority of remedies were prepared from fresh plant materials (84.6%), with crushing being the predominant preparation method (35%). Oral administration was the most common route of application (67%). The highest informant consensus factor (ICF) was recorded for plants used to treat respiratory diseases (ICF = 0.97), followed by dermatological conditions (ICF = 0.88).

Conclusion: The study area hosts a diverse array of medicinal plants, underscoring its importance as a valuable source of ethnoveterinary knowledge. Further research is essential to explore the phytochemical properties, antibacterial activities, modes of administration, and to establish standardized dosages for these medicinal plants.