Reproduction in Domestic Animals最新文献

Semen quality is the most crucial indicator for evaluating the reproductive capacity of boars. Semen traits, including semen volume, sperm density, motility and abnormality rate, exhibit low to moderate heritability, making genetic improvement through conventional breeding challenging. Advances in genome sequencing have enabled GWAS to identify genetic markers for economically important traits. In this study, 172 Large White boars with 56,427 phenotypic records across seven semen quality traits were subjected to 15× whole-genome resequencing. GWAS was performed using the FarmCPU model, identifying 2824 significant SNPs and annotating 573 candidate genes associated with seven semen traits. After linkage disequilibrium (LD)-based clumping (r² < 0.1, 1 Mb window), 916 independent genomic loci were identified as significantly associated with the seven semen quality traits. Functional analysis revealed key biological processes, including growth regulation, extrinsic apoptotic signalling pathway and the TOR signalling pathway. In an expanded population, six SNPs associated with semen quality traits were identified in the SOX6, CACNA1H, FOXP4, EFNA3 and ITGA9 genes. Significant associations were found between SOX6 gene and sperm abnormality rate, CACNA1H gene and semen volume, sperm density, motility, and abnormality rate, FOXP4 gene and sperm density, EFNA3 gene and semen volume, sperm density, ITGA9 gene and semen volume, sperm density, motility, and abnormality rate. These findings enhance understanding of the genetic architecture of boar semen quality and provide molecular markers for genetic selection, facilitating improved breeding strategies.

For approximately 40 years, microencapsulation technology has been utilised across various species due to its ability to release semen gradually after artificial insemination. This study aimed to establish the use of the alginate microencapsulation procedure for goat semen and to investigate whether this method enhances longevity during cold storage compared to the traditional straw method. Semen was collected from Canindé bucks and analysed using Computer-Assisted Semen Analysis (CASA). The semen was then diluted in a commercial extender and packaged either in straws or microcapsules (using 1% sodium alginate). Both groups were refrigerated at 4°C-5°C and assessed at 24, 48 and 72 h after dilution. The evaluation included assessments of sperm viability, abnormalities, membrane integrity, and DNA integrity. Data were analysed using repeated-measures ANOVA at p < 0.05. Concerning the parameters straight line (VSL) and average path (VAP), no statistical differences (p > 0.05) were observed. However, the microcapsule group showed significantly higher results (p < 0.05) for straightness (STR), beat cross frequency (BCF), and wobble (WOB) at 24 and 48 h of storage. Sperm viability was also higher (p < 0.05) in the microcapsule group at 24 and 48 h of storage. In conclusion, this study demonstrates the feasibility of microencapsulating goat semen. Further in vivo and/or in vitro fertility trials are needed to confirm these findings.

Glutathione peroxidase (GPx), a crucial element of anti-oxidative defence, is known to enzymatically ward off lethal free radicals released from redox metabolism within the sperm. However, in vitro semen chilling procedures gravely affect the scavenging capacity of antioxidants to counter reactive oxygen species (ROS) and dismantle the cellular structures. This directs towards the integration of exogenous antioxidants into the semen freezing medium. Japanese quail, not fully exploited yet because of high sensitivity to inbreeding, if propagated via assisted reproduction, could enormously contribute to fulfill the escalating poultry demand. Therefore, the current study aimed at investigating the effect of GPx fortification on the quality, mitochondrial activity, antioxidant potential and lipid peroxidation (LPO) of cryopreserved Japanese quail semen. For this purpose, pooled semen (30 males) was divided and diluted with NaCl extender (1:15) having 5, 10 15 U GPx/mL and control. Samples were cryopreserved and evaluated for the quality and biochemical activity at post-dilution, post-cooling, post-equilibration and post-thaw stages of cryopreservation. The sperm motility (η_p ² = 0.617), plasma membrane integrity (η_p ² = 0.666), viability (η_p ² = 0.691), mitochondrial status (η_p ² = 0.710), total antioxidant potential (η_p ² = 0.674) and free radical scavenging capacity (η_p ² = 0.680) were recorded highest (p < 0.05) in samples containing 5 U GPx/mL compared to other concentrations and control at all the stages of freezing. Moreover, the lowest LPO was recorded in the samples with 5 U GPx/mL followed by 10 U GPx/mL, control and 15 U GPx/mL throughout the stages of cryopreservation. The study concluded that GPx at 5 U/mL maintains the quality and scavenging capacity of cryopreserved Japanese quail semen against ROS accumulation.

In mammals, the corpus luteum (CL) is an endocrine gland whose function and survival are limited in scope and time. Although the CL produces progesterone to maintain pregnancy, regression of the CL is necessary for initiating the estrous cycle. A previous study showed that prostaglandin F2α (PGF2α) is a luteolysis hormone that causes CL regression by inducing luteal cell apoptosis. Although much is known about the role of PGF2α during luteolysis, the functions of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) in PGF2α-induced CL regression are unclear. In this study, goat luteal cells were treated with PGF2α to trigger apoptosis. We found that ER stress was induced by PGF2α treatment. Additionally, the ER stress-mediated UPR was activated through its three sensors (IRE1, ATF6 and PERK) in goat luteal cells. By applying different ER stresses, we revealed the role of ER stress in PGF2α-induced apoptosis in goat luteal cells. Further, IRE1 knockdown inhibited mitochondrial pathway-mediated apoptosis in luteal cells. Together, our results indicate that the ER stress-mediated UPR promotes goat luteal cell apoptosis, which is related to IRE1 activation in mitochondrial pathway-mediated apoptosis. This present work may provide new insight into the mechanistic pathways of regulating regression of goat CL.

Post-mortem oocyte collection serves to preserve the genetic material of valuable mares and to obtain recipient oocytes for cloning purposes. Therefore, the number of oocytes retrieved per ovary is a critical factor in increasing the likelihood of obtaining a viable embryo. This study evaluated the efficiency of two post-mortem oocyte retrieval techniques: follicular scraping (Scraping) and ultrasound-guided follicular aspiration (OPU). The comparison was based on several parameters, including the number of follicles aspirated per ovary, oocyte recovery rate (ORR), number of oocytes obtained per ovary, processing time, oocyte searching time, and the volume of medium used. A total of 22 replicates were performed (11 for each group), processing 28 ovaries in the Scraping group and 22 ovaries in the OPU group. Oocytes were searched by the same operator, who was blinded to the treatment group. The results demonstrated that the OPU technique was significantly more efficient than Scraping in most evaluated parameters: number of follicles aspirated per ovary (13.6 ± 3.8 vs. 9.5 ± 3.5), oocytes recovered per ovary (9.1 ± 3.0 vs. 4.7 ± 2.1), processing time per oocyte (1.8 ± 0.8 min vs. 4.1 ± 1.6 min), and ORR (66.7% vs. 50%) (p < 0.05). No significant difference was found in the volume of medium used (19.6 ± 10.4 vs. 21.6 ± 11.0 mL). However, the OPU technique resulted in more denuded oocytes (37.5%) than the Scraping technique (18.6%; p < 0.05). In conclusion, ultrasound-guided follicular aspiration yielded a higher number of oocytes per ovary compared to the standard scraping technique.

This study evaluated the effects of cholesterol, pentoxifylline and casein, with or without skim milk, added to extenders during pre-centrifugation on equine sperm cryosurvival. Seven ejaculates from four stallions (n = 28) were divided into four groups: SM (skim milk), SMP (SM + pentoxifylline), SMCho (SM + cholesterol) and ChoCa (cholesterol + casein). After centrifugation and freezing, sperm kinematics and plasma membrane integrity were assessed immediately and 30 min post-thaw. SMCho and ChoCa showed superior results compared with SM and SMP. These findings indicate that cholesterol-based extenders improve post-thaw sperm quality when added before cryopreservation.

Cattleyak is a hybrid between cattle and yak; the underlying mechanism for its spermatogenic arrest is still unclear, and it's a typical male sterile mammal. In this work, we cloned the OTUD6A gene of cattleyak and analyzed it by bioinformatics. The expression level of OTUD6A in testicular tissues and undifferentiated spermatogonia of cattleyak was significantly lower than that in yak (p < 0.05). Overexpression of OTUD6A in cattleyak promoted the viability and proliferation activity of cattleyak undifferentiated spermatogonia (p < 0.05). Furthermore, OTUD6A overexpression resulted in significant upregulation of genes associated with proliferation (p < 0.05). Therefore, the aberrant expression of OTUD6A in undifferentiated spermatogonia of cattleyak impaired its proliferation and decreased its growth potentiality, thereby affecting the development of undifferentiated spermatogonia. This study provided a new theoretical basis for further elucidation of the molecular mechanism of spermatogenesis arrest in cattleyak.

This paper reviews research on indigenous goat breeds in Ethiopia, focusing on economically important traits. The objective is to compile and document findings on the potential of these breeds while identifying research gaps and future directions. Relevant literature was collected for 3 months using Scopus-indexed Google Scholar and PubMed databases. The review highlights that the growth and reproductive efficiency of indigenous goats vary due to differences in management practices, breed characteristics, and community-based breeding programs. Selective breeding has effectively improved key traits in livestock, including birth weight, weaning weight, and yearling weight, leading to improved growth performance. Traditional management systems resulted in delayed puberty, lower litter size, longer kidding intervals, and high mortality rates. Improved management systems lead to higher milk yields, larger litter sizes, and better survival rates. Indigenous goats in lowland areas have longer kidding intervals, lower body weights, and less selection pressure compared to those in midland and highland regions. Although productivity is generally low under traditional systems, Ethiopian indigenous goats show great potential with improved management. Community-based breeding programs are crucial for improving these breeds in low-input production systems.

In equine reproduction, determining foetal sex is of economic and strategic importance, but currently available methods are often invasive, costly, or require specialised expertise. This study aimed to assess whether plasma progesterone concentrations could serve as a predictive tool for foetal sex determination in Criollo mares between the 4th and 8th months of gestation and to determine whether these measurements could identify foetal sex. Blood samples were collected at 30-day intervals from 17 Crioula mares between 114 days and 240 days of gestation. Maternal plasma progesterone concentrations were determined by radioimmunoassay and the sex of the foals was confirmed at birth. Analysis of Variance (ANOVA) was made to verify the variation in maternal progesterone concentrations according to foetal sex and month of gestation. In mares carrying male foetuses (n = 7), there was a significant difference in progesterone concentrations between months 4 and 8, as well as between months 7 and 8. In mares carrying male foetuses (n = 7), progesterone concentrations were higher (p = 0.028) during the 4th month of gestation and lower at the 8th month (p = 0.020), compared to the values in mares with female foetuses (n = 10). In the 8th month of pregnancy, the sensitivity and specificity of progesterone concentrations for the predicted sex were 80% and 100%, respectively. A limit value of progesterone (12.45 ng/mL) was established through the ROC (receiver operating characteristic) Curve. Prediction values were 78.8% and 100% for males and females, respectively. Detection rates were 100% and 80% for males and females, respectively. The diagnostic accuracy for both sexes was 88.2%. It is concluded that foetal sex influences plasma concentrations of progesterone in pregnant mares.

Cystic ovarian disease is one of the leading causes of infertility in dairy cows. In this experimental field study, the comparative efficacy of the -3hCG/Ovsynch protocol (pre-treatment with hCG before Ovsynch) was investigated alongside the Ovsynch and the progestagen-based Ovsynch protocol. A total of 45 dairy cows with follicular cyst (FC) were enrolled in the study. The cows were randomly divided into three equal groups: in the first group, the Ovsynch-48 protocol (Day 0 GnRH, Day 7 PGF_2α, Day 9 GnRH and fixed-time artificial insemination (FTAI) 16-20 h later); in the second group, the CIDR-synch protocol (Day 0 GnRH and the insertion of CIDR into the vagina for 7 days, Day 7 PGF_2α, Day 9 GnRH and FTAI 16-20 h later); and in the third group, the -3hCG/Ovsynch protocol (3000 IU hCG pre-treatment before initiation of the Ovsynch-48 protocol) were applied. Blood samples were collected on Day -3, 0, 3 and 7, and serum progesterone levels were measured. Transrectal sonography of the ovaries was performed on Day -3, 0, 3 and 7 for ovarian dynamics (follicular development, presence of FC, measurement of diameter and wall thickness of FC) throughout the protocols. Cows were fixed-time artificially inseminated. On Day 13 (3 days after FTAI) and Day 45 (pregnancy diagnosis), ovarian ultrasonography was also performed to evaluate the cystic persistence (PC). hCG pre-treatment was found to be ineffective on follicular development in the early period of the -3hCG/Ovsynch protocol, but it significantly increased the diameter of the dominant follicle on Day 3 when compared to the Ovsynch and CIDR-synch protocols. The lifespan of the corpus luteum in the -3hCG/Ovsynch group was longer (> 4 days) than in the other protocols (< 4 days). Following the Ovsynch, CIDR-synch and -3hCG/Ovsynch protocols, the PC rates were found to be 54.5% (6/11), 45.4% (5/11) and 27.2% (3/11) on Day 13, and 27.2% (3/11), 27.2% (3/11) and 9.1% (1/11) on Day 45, respectively. Conception rates were found in Ovsynch (6/15), CIDR-synch (8/14) and -3hCG/Ovsynch (8/15) protocols as 40%, 57.1% and 53.3%, respectively. According to the findings, it was concluded that the -3hCG/Ovsynch protocol may be more effective than the Ovsynch protocol in the treatment of cows with FCs, can be used as an alternative to the CIDR-synch protocol and can be preferred especially in cows with uterine infection detected early in the postpartum period and in cases where the use of exogenous progesterone is contraindicated.