Animals最新文献

The increasing volume of genome sequencing data presents challenges for traditional genome-wide prediction methods in handling large datasets. Machine learning (ML) techniques, which can process high-dimensional data, offer promising solutions. This study aimed to find a genome-wide prediction method for local pig breeds, using 10 datasets with varying SNP densities derived from imputed sequencing data of 515 Rongchang pigs and the Pig QTL database. Three reproduction traits-litter weight, total number of piglets born, and number of piglets born alive-were predicted using six traditional methods and five ML methods, including kernel ridge regression, random forest, Gradient Boosting Decision Tree (GBDT), Light Gradient Boosting Machine, and Adaboost. The methods' efficacy was evaluated using fivefold cross-validation and independent tests. The predictive performance of both traditional and ML methods initially increased with SNP density, peaking at 800-900 k SNPs. ML methods outperformed traditional ones, showing improvements of 0.4-4.1%. The integration of GWAS and the Pig QTL database enhanced ML robustness. ML models exhibited superior generalizability, with high correlation coefficients (0.935-0.998) between cross-validation and independent test results. GBDT and random forest showed high computational efficiency, making them promising methods for genomic prediction in livestock breeding.

The state of frailty is a clinical-biological syndrome that affects the older population with a higher risk of functional dependence. Animal models can provide a tool to study this complex scenario. In the present work, we analyzed the physical and behavioral hallmarks of end-point status in 16-month-old mice (C57BL/6J) according to animal welfare regulations compared to age-matched counterparts with normal aging. A group of 6-month-old mice was added to control for age bias. First, we identified 'structural kyphosis' (visible and unmodifiable deformation in locomotion) correlated with piloerection as the hallmarks of the physical frailty phenotype compared to the 'postural kyphosis' (adjustment to counteract increased visceral volume but attenuated during locomotion) of old mice with normal aging. Alopecia (barbering) was presented in both old groups. Normal levels of exploratory activity in the corner test for neophobia and triceps surae muscle weight but an increased latency of rearing indicated the poorest emotional phenotype, with a possible contribution of structural kyphosis. The presence of hepatomegaly and splenomegaly counteracted the significant WAT loss commonly associated with end-of-life traits, which should have a normal body weight but preserved muscle mass.

PCV-3 and PCV-4 are novel viruses that can infect domestic pigs and wild boars. Both viruses are associated with multiple disorders in domestic pigs (reproductive failure, respiratory damage, etc.). However, the clinical impact on wild boars remains unknown. This study aimed to assess the presence of these viruses in wild boars from mid-western Spain and their sanitary impact on the species. A total of 166 submandibular lymph nodes were collected from hunted wild boars, along with available information about their reproductive status, lung injuries, body condition, and tuberculosis status. The samples were used to detect PCV-3 and PCV-4 using real-time PCR. In total, 84.9% of the sampled animals were positive for PCV-3, and 33.7% were positive for PCV-4. The detection of PCV-4 was more frequent in wild boars that had received supplementary feeding, suggesting that the direct contact favored by this practice could increase the transmission of this virus in wild boar populations. The infections did not seem to influence the body condition, reproductive status, lung lesions, or TB lesion severity patterns in the studied animals. Thus, although these viruses have been widely detected throughout wild boar populations from the studied area, they do not seem to be a health threat to this species. Nevertheless, their monitoring in wild boars is recommended, as they are often in contact with extensively reared pigs, which are susceptible to these viruses.

Understanding the genetic, physiological, and nutritional characteristics of native chickens in South Africa has been significantly hindered by studies over the last ten years. These chickens hold significant economic, social, and cultural importance for South African communities, particularly those marginalized. Despite their reputation for lower egg productivity, they are highly valued for their flavorful meat by consumers. Many local chicken ecotypes and breeds remain undocumented and in danger of going extinct, even though some have been classified. To tackle this issue, the Food and Agriculture Organization has launched an indigenous poultry conservation program. One crucial method employed is assisted reproductive biotechnologies such as cryopreservation, which serves as an ex situ conservation strategy for preserving the germplasm of endangered animals. In avian species, cryopreservation is particularly beneficial for the long-term storage of sperm cells, although it necessitates the use of cryoprotectants to shield sperm cells from cold shock during freezing. However, the use of cryoprotectants can lead to thermal shocks that may damage the sperm cell plasma membrane, potentially reducing viability and fertility. Furthermore, the membranes of avian sperm cells are highly polyunsaturated fatty acids, which can undergo lipid peroxidation (LPO) when reactive oxygen species (ROS) are present. This review focuses on current knowledge and the latest effective strategies for utilizing cryopreservation to conserve semen from indigenous poultry breeds.

Multicentric lymphoma is the most common type of hematopoietic neoplasm in dogs. Chemotherapeutic protocols typically consist of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP). The 15- and 19-week CHOP protocols exhibit similar outcomes, indicating that a shorter treatment duration may be a feasible treatment option. However, the 19-week LHOP protocol, which uses L-asparaginase instead of cyclophosphamide, results in a longer progression-free survival and a similar survival time compared to CHOP-based chemotherapy regimens. In this study, we conducted and historically compared the efficacy of the 15- and 19-week LHOP protocols to determine whether there are any differences in efficacy. Eighteen and twenty dogs underwent the 15- and 19-week LHOP protocols, respectively. No significant differences were found in age, body weight, sex, clinical stage, substage, T-cell phenotype, hypercalcemia status, and overall response rate between the two groups. The time to progression (TTP) and lymphoma-specific survival (LSS) for the 19-week LHOP protocol were significantly longer than those for the 15-week LHOP protocol (p = 0.004 and p = 0.008, respectively). Thus, the 19-week LHOP protocol may be a better treatment option for dogs with multicentric lymphoma. However, the 15-week LHOP protocol lowered the treatment cost and reduced the treatment time.

The yak industry constitutes a pivotal segment of livestock development across the Qinghai-Tibetan Plateau and adjacent pastoral regions. Existing studies have shown that supplemental feeding for grazing yaks significantly improves meat quality and growth performance, but its effect on enteric methane (CH₄) emission from yaks has never been reported, so the present experiment aimed to investigate the effect of supplemental feeding of grazing yaks on CH₄ emissions in three different periods of the warm season. Thirty male yaks were randomly assigned to two groups, with 15 yaks per group, The groups were designated as the grazing group (GR), with traditional grazing methods and with an initial body weight of 94.56 ± 3.9 kg, and the supplemental feeding group (GRS) with an initial body weight of 95.01 ± 4.1 kg, which received 1500 g/d of supplemental feed for 120 days. The methane emissions of the two groups were measured at the late regreening period (LRP), the greening-grass period (GGP), and the browning period (BRP) using the SF₆ tracer method. The results showed that GRS increased (p < 0.01) the total DMI during warm season but decreased (p < 0.01) the forage intake at the LRP and GGP, resulting in a significantly reduced methane yield per kg of BW gain and per kg of DMD in warm-season grazing yaks (p < 0.01), a significantly reduced methane production per kg of DMI and methane energy to gross energy ratio in grazing yaks during the GGP (p < 0.05), and a similarly significantly decrease in methane production per kg of DMI and methane energy to gross energy ratio in grazing yaks during the BRP (p < 0.01). In conclusion, supplemental nutrition for grazing yaks during the warm season in alpine grasslands significantly enhances growth performance, reduces methane emissions, and improves dietary energy utilization efficiency.

Continuous advancements in veterinary medicine have significantly improved the health and longevity of companion animals while also contributing to wildlife conservation efforts [...].

Clostridium butyricum, recognized as a probiotic, is widely distributed in the intestines of various animals. In this study, the C. butyricum strain YF1 was isolated from the intestine of the ricefield eel (Monopterus albus) using an anaerobic culture method and was identified through morphological, physiological, biochemical, and 16S rRNA sequence analyses. Notably, C. butyricum YF1 exhibited a rapid growth rate and was found to produce ten types of short-chain fatty acids, particularly high-yield acetic acid and butyric acid. Additionally, YF1 demonstrated a high tolerance to elevated temperatures (70 °C), bile salts (0.1% to 0.5%), artificial intestinal fluid, and artificial gastric fluid, while being sensitive to most antibiotics. Further whole-genome sequencing revealed that C. butyricum YF1 has a total genome size of 4,314,266 bp and contains 3853 coding genes. Specifically, 82 tRNAs, 21 rRNAs, 288 repeat sequences, 13 prophages, and two gene islands were detected. Moreover, gene function analysis indicated that the highest number of genes were annotated to metabolic processes, and the butyric acid metabolism pathway was found to be complete. Meanwhile, 598 virulence genes and 186 resistance genes were predicted. In conclusion, the findings from this study contribute to probiotic development and provide innovative approaches for the sustainable and healthy cultivation of ricefield eels.

Behavioural synchronization in dogs has been examined separately at intraspecific and interspecific levels. This study is the first to compare dogs' behavioural synchronization and gaze behaviour when with a familiar person (with FP) compared to a familiar dog (with FD), while walking in an outdoor environment. Twenty dogs were observed under the two experimental conditions. We hypothesized that dogs would demonstrate stronger location and activity synchronization with an FD than with an FP due to similar locomotor patterns, while showing greater gaze attention towards the FP compared to the FD. Our hypothesis was partially confirmed. The results revealed a significantly shorter distance between dogs and the FD than between dogs and the FP. Dogs exhibited a smaller speed difference with the FD than with the FP, but only if they did not cohabit with other dogs. No significant differences were observed in body alignment or gaze behaviour between the two experimental conditions. Our results point to behavioural synchronization as a new instance of evolutionary convergence, as well as daily experiences, here cohabiting with other dogs, as a factor influencing dogs' ability to synchronize with individuals from different species. This study enhances our understanding of canine cognition in conspecific versus heterospecific contexts.

The aim of this study was to evaluate the effectiveness of different anesthetic protocols for semen collection from healthy tomcats using Urethral Catheterization after Pharmacological Induction (UrCaPI). Twenty sexually mature tomcats (Felis catus) were included in the study, in which high and low dosages of medetomidine or dexmedetomidine were administrated to collect semen. Ten healthy mature tomcats (Group A) received high dosages of the drugs, and, in particular, five of them were i.m. injected with 120 μg/kg of medetomidine (HMED) on day 1 and with 60 μg/kg of dexmedetomidine (HDEX) after 24 h (day 2). The remaining five tomcats of this group were i.m. injected with 60 μg/kg of dexmedetomidine on day 1 and with 120 μg/kg of medetomidine on day 2. The other ten healthy mature tomcats (Group B) received a low dosage of the same drugs; the first five tomcats were i.m. injected with 50 μg/kg of medetomidine (LMED) on day 1 and with 25 μg/kg of dexmedetomidine (LDEX) on day 2; the others were i.m. injected with 25 μg/kg of dexmedetomidine on day 1 and with 50 μg/kg of medetomidine after 24 h. In both groups, semen collection was performed as soon as the pharmacological effect of the drug was reached. All protocols permitted sperm collection, even if with different results in quality for volume, concentration, total number of spermatozoa, and movement score. Results suggest that both a high dosage of medetomidine and a high dosage of dexmedetomidine could be used for the collection of good-quality semen. Semen volume μL: HMED = 32 μL (25.75-37.5), HDEX = 23 μL (15.25-28). Concentration HMED = 670 × 10⁶/mL (576-990.5), HDEX = 670.5 × 10⁶/mL (536-790). Total number of spermatozoa = 23.24 × 10⁶ (18.37-32.05). Total number of spermatozoa = 13.121 × 10⁶ (10.116-16.83). However, the protocol with dexmedetomidine could not always guarantee an adequate sedation for urethral catheterization, so using a high dosage of medetomidine is still the better way to collect high quality semen with the UrCaPI technique. The outcome of the LMED and LDEX protocols was generally unsatisfactory regarding both level of sedation and semen collection in terms of volume (LMED = 3 μL (4-7.5); LDEX = 6 μL (4-7)), concentration (LMED = 215 × 10⁶/mL (157-248); LDEX = 27.05 × 10⁶/mL (0.040-110), total number of spermatozoa (LMED = 0.88 × 10⁶ (0.581-1.38); LDEX = 0.16 × 10⁶ (0.0001-0.80), and movement score (LMED = 3 (2-3); LDEX = 2 (0-2.75)).