Frontiers in Veterinary Science最新文献

This study continued the in vitro screening of locally available ruminant feedstuffs for optimum nutrient composition and low methane (CH₄) production in Ethiopia. The best bet feeds from the in vitro study, hereafter called the test feeds, include dried leaves of Acacia nilotica, Ziziphus spina-christi, and brewery spent grains (BSG). The study involves four treatments: Control, Acacia, BSG, and Ziziphus; each treatment provided an equivalent crude protein and estimated enteric CH₄ emissions using Modeling and a Laser CH₄ detector (LMD). The experiment was designed as a randomized complete block, using initial weight as the blocking factor for 21 yearling castrated Menz sheep. The study spanned 90 days, and digestibility trials were carried out following a month of the feeding trial. The control group exhibited a significantly (p < 0.001) lower dry matter intake (DMI) compared to the test feed group, which had a higher intake, particularly in the Ziziphus group. However, the Ziziphus group demonstrated significantly (p < 0.01) lower CP digestibility than the other groups. The test diet also led to a significantly (p < 0.001) higher weight gain. Notably, the Ziziphus group demonstrated superior performance in weight change (BWC), final body weight (FBW), and average daily gain (ADG). Similar results were observed for CH₄ production (g/day), CH₄ yield (g/kg DMI), and CH₄ intensity (g CH₄/kg ADG) using both CH₄ measuring methods. The CH₄ emission intensity was significantly (p < 0.04) lower in the test feed groups than in the control group. The control group emitted 808.7 and 825.3 g of CH₄, while the Ziziphus group emitted 220 and 265.3 g of CH₄ per kg of ADG using the Modeling and LMD methods, respectively. This study indicates that LMD could yield biologically plausible data for sheep. Although the small sample size in the Ziziphus group was a limitation of this study, leaf meals from Ziziphus spina-christi and Acacia nilotica, which are rich in condensed tannins (CTs), have resulted in considerable weight gain and enhanced feed efficiency, thereby making these leaf meals a viable and sustainable feed option for ruminants in Ethiopia.

Long non-coding RNAs (lncRNAs) are RNA molecules exceeding 200 nucleotides in length. Recent studies have demonstrated their involvement in regulating gene expression and various biological processes. Among these, myogenesis and lipogenesis are particularly important because of their direct effects on muscle development and fat deposition in farm animals. These processes are crucial for determining meat quality, growth rates, and overall economic value in animal husbandry. Although the specific mechanisms through which lncRNAs influence these pathways are still under investigation, further research into their roles in muscle and fat development is crucial for optimizing farm animal breeding strategies. Here, we review the characteristics of lncRNAs, including their biogenesis, localization, and structures, with a particular focus on their association with myogenesis and adipogenesis. This review seeks to establish a theoretical foundation for enhancing farm animal production. In particular, focusing on lncRNAs may reveal how these molecules can enhance the economic traits of farm animals, thereby contributing to the optimization of farm animal breeding processes.

Feline coronavirus (FCoV) is a significant pathogen that infects the feline population worldwide. FCoV can cause mild enteric disease and a fatal systemic disease called feline infectious peritonitis (FIP). In this study, a cross-sectional survey of FCoV in domestic cats from small animal hospitals in Thailand was conducted from January to December 2021. Our result showed that out of 238 samples tested for FCoV using 3' UTR-specific RT-PCR, 18.7% (28/150) of asymptomatic cats and 25.5% (12/47) of cats with unknown status tested positive for FCoVs. Additionally, 51.2% (21/41) of cats with suspected FIP were found to be positive for FCoVs. Genotype identification using S gene-specific RT-PCR showed that all FCoV-positive samples (n = 61) were FCoV type I. This study obtained the whole genome sequences (n = 3) and S gene sequences (n = 21) of Thai-FCoVs. Notably, this study is the first to report the whole genome of Thai-FCoV. Phylogenetic analysis indicated that Thai-FCoVs were closely related to FCoVs from China and Europe. Additionally, the Thai-FCoVs exhibited specific amino acid substitutions (M1058L) associated with the pathotype switch. Recombination events were found to mainly occur in the ORF1ab and S gene regions of Thai-FCoVs. This study provides insights into the occurrence, genetic diversity, virulence amino acid mutations, and potential recombination of FCoVs in the domestic cat population in Thailand, contributing to our understanding of FCoV epidemiology.

Heat stress poses a significant challenge in communal feedlot systems, affecting cattle welfare and productivity. This study evaluated the impact of shade and water-cooling interventions on thermophysiological stress reduction and growth performance in 60 cattle from communal feedlots. Physiological indicators (rectal temperature, skin temperature, respiration rate) along growth metrics (feed intake, average daily gain [ADG]) were analyzed using regression and principal component analysis (PCA) to identify key drivers of performance. The results showed a significant reduction (p < 0.05) in rectal temperature, respiration rate, and skin temperature in cattle subjected to shade and water cooling compared to the control group. Temperature-Humidity Index (THI) values frequently exceeded the heat stress threshold of 72, with peak mid-day values surpassing 80, indicating severe thermal stress. Cattle in the treated groups experienced lower THI values, reduced panting scores, and improved homeostasis under high thermal loads. Breed-specific differences were evident, with Bos indicus cattle (Nguni) maintaining lower physiological stress indicators than Bos taurus (Bonsmara), highlighting superior heat tolerance. Growth performance, measured by average daily gain (ADG) and feed conversion ratio (FCR), significantly improved in the treated groups, with ADG increasing by 18% and FCR improving by 12% relative to the control. Blood metabolite analysis revealed lower cortisol levels (p < 0.05) and improved electrolyte balance in the cooled groups, indicating reduced chronic stress and better metabolic function. Behavioral observations, recorded at 10-min intervals every 30 min, showed increased resting time and reduced panting frequency in cooled cattle, confirming enhanced thermal comfort. These findings underscore the importance of integrating cooling interventions into cattle management strategies to improve productivity and welfare in heat-stressed environments.

This study was conducted to evaluate the effects of dietary mixed selenium [MSe: inorganic selenium (ISe) + organic selenium (OSe)] levels on the growth performance, blood parameters, and fecal microbiota of weaned pigs. In a randomized complete block design (block = initial body weight), 156 weaned pigs were allotted to three dietary treatments (4 pigs per pen; 13 replicates per treatment) for 42 days. Dietary treatments included (1) a non-Se-fortified diet based on corn and soybean meal (CON), (2) CON + 0.15 ppm ISe and 0.15 ppm OSe (MSe3), and (3) CON + 0.25 ppm ISe and 0.25 ppm OSe (MSe5). Pigs fed both MSe diets showed no effects on growth performance or diarrhea frequency compared with those fed the CON diet. However, pigs fed MSe3 and MSe5 had higher serum interleukin-6 (p = 0.021, linear p = 0.011) on day 7 and higher Se concentrations (p = 0.002, linear p = 0.001) on day 42 than those fed the CON. In addition, pigs fed different levels of MSe exhibited quadratic (p = 0.054) and linear (p = 0.069) effects on the number of white blood cells and hematocrit on day 42 compared with those fed CON, respectively. Moreover, the MSe3 group had higher total protein concentration (p = 0.049, quadratic p = 0.026) on day 42 than the CON group, and the MSe5 group had lower blood urea nitrogen concentration (p = 0.094, linear p = 0.033). There were no differences in alpha diversity indices of fecal microbiota among dietary treatments. However, beta diversity indices based on the Bray-Curtis dissimilarity were clustered differently (r ² = 0.56, p = 0.001) among dietary treatments. Pigs fed the MSe5 diet showed an increase in the relative abundance of phylum Bacteroidetes [false discovery rate (FDR) adjusted p = 0.004], families Barnesiellaceae (FDR adjusted p = 0.006) and Veillonellaceae (FDR adjusted p = 0.006), genera Barnesiella (FDR adjusted p = 0.023) and Megasphaera (FDR adjusted p = 0.023), and species Barnesiella intestinihominis (FDR adjusted p = 0.016) and Megasphaera elsdenii (FDR adjusted p = 0.019) compared with those fed the CON diet. In conclusion, dietary MSe modulated the systemic health parameters and fecal microbial community in weaned pigs.

Introduction: Intracranial dermoid cysts (IDCs) are rarely observed in veterinary medicine, and reports regarding treatment strategies for feline IDCs are severely lacking. This report describes the surgical management of epileptic seizures caused by IDCs in a cat.

Case presentation: An 8-year-old, spayed, female American Shorthair cat presented with epileptic seizures. The epileptic seizures, which had developed at the age of 5 years, had been controlled by phenobarbital administration. At 8 years old, the cat contracted acute hepatitis, prompting a switch from phenobarbital to other antiseizure medications. This drug switch caused an increase in the frequency of epileptic seizures. Magnetic resonance imaging (MRI) revealed a dermoid cyst as a heterogeneous intensity mass on T2-weighted images, without falx cerebri displacement. The preoperative seizures occurred more than three times a day (cluster seizures), even though the cat was administered multiple antiseizure medications. The seizures ceased after surgical removal of the dermoid cyst. The cat did not experience seizures for 14 months after surgery, even with discontinuation of antiseizure medications.

Conclusion: In cats, surgical removal of frontal lobe IDCs may effectively control epileptic seizures without fatal complications, thus potentially leading to a great prognosis.

Objective: To compare efficacy of four techniques used for medial meniscal release by medial caudal meniscotibial ligament transection and evaluate associated iatrogenic damage to the medial meniscus, caudal cruciate ligament (CdCL), and articular cartilage of the canine stifle joint.

Study design: Twenty-four pairs of canine cadaveric pelvic limbs were randomly assigned to groups by methods of approach, cranial tibial translation, and meniscal release. I: arthrotomy, Hohmann, #11 scalpel blade; II: arthrotomy, Hohmann, #64 Beaver blade; III: arthroscopy, Hohmann, meniscal hook knife; IV: arthroscopy, no joint translation, meniscal hook knife. Post-procedure stifle dissection and evaluation of meniscal release success rate and presence of iatrogenic damage were performed. Fisher's exact tests were performed for meniscal release and damage comparisons. Iatrogenic damage to the CdCL and articular cartilage were compared using generalized linear mixed effects model and linear mixed effects models (G/LMM) respectively.

Results: Incomplete meniscal release was identified in 0/12 (0%) stifles in group I, 1/12 (8.3%) stifles in group II, 2/12 (16.7%) stifles in group III, and 1/12 (8.3%) stifles in group IV (p = 0.89, Fisher's exact test). There was no difference in iatrogenic meniscal damage rates between groups (p = 0.48, Fisher's exact test). There were no differences in total surface area of iatrogenic articular cartilage damage in any tested region between groups: femoral trochlea (p = 0.32, LMM), femoral condyles (p = 0.54, LMM), tibia (p = 0.28, LMM). Group I had more iatrogenic damage to the CdCL than group IV (p = 0.04, GLMM); no other differences were found.

Conclusion: Arthroscopy and arthrotomy were equally effective for performing medial meniscal release by transection of the medial caudal meniscotibial ligament. Arthroscopic evaluation and medial meniscal release without joint translation was minimally advantageous in preventing iatrogenic damage to the CdCL.

Introduction: Racehorse and jockey incidents on race-days frequently occur together, yet risk factors for their occurrence have historically been investigated separately. Consideration of both horses and humans in tandem is required for a One Health approach to risk reduction. Our objectives were to therefore identify modifiable risk factors for adverse outcomes that are common or conflicting to both horses and their jockeys in Thoroughbred racing.

Methods: Australian Single National System records for the 2004/05 to 2018/19 flat racing season were merged with the corresponding Australian Racing Incident Database records. Incidence rate ratios (IRR) with 95% confidence intervals (CI) were estimated for the outcomes of racehorse musculoskeletal injury (MSI), racehorse fatality, jockey falls and jockey injury using Poisson regression. Horse-level, race-level, jockey-level and trainer-level factors associated with each adverse outcome during or post-race were identified using multivariable logistic regression.

Results: The incidence of MSI was 21.21 (20.84, 21.59), racehorse fatalities 0.55 (0.50, 0.61), jockey falls was 3.01 (2.80, 3.24), and jockey injuries 1.79 (1.63, 1.97) per 1000 flat race starts. There was a decrease in racehorse MSI and jockey falls over the study period but no change in racehorse fatality or jockey injury incidence. In multivariable analysis, longer race distances and higher caliber races were associated with horse (p < 0.01), but not jockey, incidents. Firmer turf surfaces were associated with greater risk of both horse incidents and jockey falls (p < 0.05). Racehorses that were of older age at their first start, and/or had prior race-day injuries had a greater risk of injury and fatality (p < 0.001, p < 0.01, respectively). The most prominent risk factor for jockey fall or injury was a racehorse incident, although overall contributing to a relatively small proportion; 8.6% (n = 42/489) of jockey falls and 15.3% (n = 24/147) of injuries. Jockeys with fewer career starts were at greater risk of falling, and those with a higher percentage of last place finishing positions were at greater risk of injury (p < 0.001).

Discussion: As there were no conflicting risk factors identified between racehorse and jockey injury, policies aimed at reducing horse injury risk are also expected to benefit their riders.

Introduction: Brucellosis is a zoonotic disease that affects both dogs and humans. With the increase in dog ownership, the risk of transmission has risen for both adults and children.

Methods: This study used meta-analysis to comprehensively analyze the prevalence of canine brucellosis in China and to identify the relevant factors affecting its transmission.

Result: We conducted a meta-analysis of 38 studies published between January 1983 and March 2024, sourced from six databases. The results showed a higher prevalence of canine brucellosis in northern and northwestern regions of China, with Xinjiang having the highest prevalence (19.77%) and Hunan the lowest (0.23%). Significant differences were found in positivity rates across different diagnostic methods (P < 0.05), with ELISA yielding the highest positivity rate (11.6%) and PCR and SAT the lowest (3.3%). The positivity rate of stray dogs (22.6%) was significantly higher than that of other dog sources (P < 0.05). Furthermore, environmental factors, such as temperature and altitude, were identified as influencing the incidence of brucellosis.

Discussion: In conclusion, canine brucellosis is prevalent across China, with detection methods, dog sources, and environmental factors contributing to the varying incidence rates. We recommend regular brucellosis testing for pet dogs, improved kennel hygiene, and reduced contact with potentially infected animals.

Systematic review registration: https://www.frontiersin.org/journals/veterinary-science.

Introduction: Understanding the impact of housing conditions on the stress responses in farmed saltwater crocodiles (Crocodylus porosus) is crucial for optimizing welfare and management practices.

Methods: This study employed a multi-omics methodology, combining targeted and untargeted LC-MS for metabolite, lipid, and hormone profiling with 16S rRNA gene sequencing for microbiome analysis, to compare stress responses and changes in fecal samples of crocodiles housed in single versus group pens. Metabolic responses to a startle test were evaluated through multivariate analysis, and changes post-stress were examined.

Results: A total of 564 metabolic features were identified. Of these, 15 metabolites were linked to the cortisol biosynthesis pathway. Metabolite origin analysis showed that 128 metabolites originated from the host, 151 from the microbiota, and 400 remained unmatched. No significant differences in fecal corticosterone levels were observed between single and group pens. However, metabolic profiling revealed distinct differences in stress responses: single pen crocodiles exhibited downregulation of certain compounds and upregulation of others, affecting pyrimidine and purine metabolism pathways when compared to grouped pen crocodiles, linked to altering energy associated induced stress. Additionally, fecal microbiome analysis indicated increased Firmicutes:Bacteroides (F:B) ratio in group-housed animals, suggesting greater stress.

Discussion: The study highlights that while traditional stress indicators like corticosterone levels may not differ significantly between housing conditions, metabolic and microbiome analyses provide deeper insights into stress responses. Single pens are associated with less metabolic disruption and potentially better health outcomes compared to group pens. These findings underscore the value of fecal microbiome and metabolomics in assessing animal welfare in farmed crocodiles.