Reproduction in Domestic Animals最新文献

In industrialized farms, rabbit does undergo intensive production rhythms which overlap lactation and gestation, leading to a high energy mobilization and increasing oxidative stress. Accordingly, we hypothesize that administration of the flavonoid quercetin (QUR) may improve the antioxidant status of young and adult rabbit reproductive females. In this study, the effect of daily oral administration of 300 mg/kg QUR for 8 weeks was assessed on the antioxidant profile of 24 New Zealand × Californian rabbit does, assigned to 4 experimental groups: rearing young (8-16 weeks old) and adult does at the end of their reproductive life (12-14 months old, with at least 3-4 reproductive cycles) treated (YQ and AQ) or not (YC and AC) with QUR, respectively. Plasma glutathione (GSH), as well as serum superoxide dismutase (SOD) and malondialdehyde (MDA) were measured during the experimental period. To assess the health status of the animals, a physical examination was also performed. GSH plasma concentrations were significantly higher in young does at weeks 1 and 4, but not at week 8 of the experiment, irrespectively of QUR administration. An increase in GSH plasma concentration was observed during the 8-week experiment in both AQ and AC groups. Furthermore, QUR administration did not alter either SOD or MDA serum activity and concentration in any group during the experimental period. Physical examination revealed no differences between the experimental groups. In conclusion, under our experimental conditions, QUR did not modify the general clinical or the antioxidant profile of young and adult reproductive rabbit females.

The main goals of this study were to document and compare the normal ranges of testicular haemodynamic parameters in pre- (aged 8-12 months; n = 4) and postpubertal (aged 24-259 months; n = 16) Miranda donkeys in the breeding season, and to correlate animal biometric data and testicular Doppler indices with basic semen quality parameters of sexually mature jacks. Colour and pulsed-Doppler ultrasonography were employed to assess blood flow in the left and right distal supratesticular artery (DsTA) and their marginal branches (marginal arteries-MA). Peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistive index (RI) were evaluated in both blood vessels, and TAMV (time-averaged mean velocity), TABF (total arterial blood flow) and TABF rate (TABF-R) were calculated for MA. The mean diameter of MA was greater (p < 0.05; 0.24 ± 0.05 vs. 0.19 ± 0.05 cm; mean ± SD) but TABF-R was less (p < 0.05; 0.004 ± 0.004 vs. 0.02 ± 0.01 mL/s/cm³) in sexually mature donkeys compared with prepubertal animals. Apart from RI values for the right testicle of prepubertal donkeys, PI and RI were consistently greater (p < 0.05) in DsTA compared with MA. Significant correlations were found among select biometric and haemodynamic attributes of the testes (height, width and length, TV, TTV and PSV-ST) and ejaculate characteristics (volume, sperm defects-total, head and midpiece) in sexually mature donkeys (n = 8). The present results highlight the importance of scrotal ultrasonography for the reproductive assessment of jacks and provide reference values, based on the available subpopulation of Miranda donkeys that can be used in their clinical and reproductive management and research, or conservation programmes.

This study was carried out on pregnant uteruses obtained from healthy Hair goats (Capra aegagrus hircus). A total of thirteen pregnant uteruses, six second and seven third trimesters, were used. Morphometrically, placentome numbers, lengths, widths and depths were measured. Randomly selected placentomes from the second and third trimesters were stained with the triple staining method. Caruncular and cotyledonary areas, capillary numbers and areas were measured using Qupath v0.5.0 software. The Minitab (version 21.4.1) was used for statistical analysis. While no statistical difference was observed in the number of placentomes between trimesters (p > 0.05), placentome length, width and depth were higher in the third trimester compared to the second trimester (p < 0.001). No difference was observed in the number of caruncular and cotyledonary capillaries in the second trimester. In the second trimester, the caruncular capillary area was higher than the cotyledonary capillary area (p < 0.05). Both caruncular and cotyledonary capillary area parameters were higher in the third trimester than in the second trimester (p < 0.001). In the third trimester, the caruncular capillary area was higher than the cotyledonary capillary area (p < 0.001). The number of caruncular capillaries and cotyledonary capillaries was statistically significantly higher in the third trimester compared to the second trimester. In addition, the number of cotyledonary capillaries was higher than that of caruncular capillaries in the third trimester (p < 0.001). A positive and significant correlation was found between the day of pregnancy and the number of placentomes in the second trimester (p < 0.05). No correlation was observed between the day of pregnancy and the number of placentomes in the third trimester. Vascular area density showed a faster development in foetal tissue than in maternal tissue. Placentome size and angiogenesis increased with the progression of pregnancy.

A new synergistic approach of classical conservation strategies combined with advanced assisted reproduction technologies (aART) allows for protection and rescue of endangered keystone species at the brink of extinction, which can help to safeguard complex ecosystems. Reproduction biology and management in mammal species is not only challenging in regards to their diverging sizes, anatomy, and often unknown physiology; it also requires customized training or chemical restraint protocols for safe handling. Besides these general challenges, there are several new assisted reproduction techniques (ART) specifically tailored to critically endangered mammals. The current portfolio of ART in these mammalian taxa is ranging from sexual cycle characterization and manipulation, semen collection and cryopreservation, artificial insemination, biobanking of living cells, oocyte collection, in vitro fertilization (IVF), and embryo production, embryo transfer as well as stem cell-derived in vitro gametogenesis for generating gametes in culture. The article covers advanced assisted reproduction technologies (aART), success and challenges, as well as ethical implications.

This study aimed to compare the effectiveness, in terms of viability and quality post-warming, when vitrifying in vitro-produced (IVP) pig blastocysts with either a modified Cryotop (n = 161; 20 blastocysts/device) or the conventional Superfine Open Pulled Straw (SOPS; n=160; 5-6 blastocysts/device systems. Blastocyst viability, morphology, and apoptosis parameters were evaluated after 24 h of in vitro culture. The Cryotop system yields better results in terms of higher embryo viability and total cell numbers (p < .05) and lower apoptosis (p < .05) parameters than the SOPS procedure, defining a high effectiveness to simultaneously vitrify 20 pig IVP blastocysts at one time, thus increasing the yield of IVP blastocysts readily available for embryo transfer.

Kenney-Doig scale is considered the international standard method for classifying uterine biopsies in mares; however, its objectivity has been questioned by various studies. In the present study, we analysed the degree of agreement between two pathologists when assessing the same set of 201 uterine biopsies, obtaining a slight to moderate level of agreement (κ = .34/κ_w = .57). Subsequently, we developed a numerical scale based on the evaluation of histological parameters, including inflammation, fibrosis, glandular density and lymphatic lacunae. Partial scores were summed to obtain a fifth parameter called Summation. The correlation between both scales was demonstrated (p < .0001), and their combined use resulted in a notable increase in the degree of agreement between the two pathologists (κ = .53/κ_w = .67).

This study investigates the impact of bovine serum albumin (BSA) inclusion in the thawing extender on boar sperm quality. Thawing protocols in sperm cryopreservation are vital, yet underexplored. It has been determined that BSA can interact with membranes, stabilizing them and preventing damage during the freezing process, for this reason it could also have a beneficial effect during thawing. Our study explores modifications in the conventional Beltsville thawing solution, incorporating BSA at different concentrations (0.005, 0.01, 0.025 and 0.050 g/mL), and evaluating the sperm quality after up to 150 min post-thawing incubation (37°C). All BSA concentrations preserved plasma membrane and acrosome integrity, relative to control (BSA absence). In addition, 0.025 g/mL BSA group preserves acrosome integrity over time without compromising motility or kinetic parameters. Our study suggests that BSA inclusion in thawing extenders should be considered as an additive for improving post-thaw boar sperm quality.

Assisted reproductive technologies (ART) play a crucial role in conserving threatened wildlife species such as Bos gaurus. ART requires a large number of mature oocytes, and small antral follicles (SAFs) in the ovary are often used to obtain abundant sources of bovine oocytes. However, oocytes from SAFs often experience difficulty completing maturation and obtaining high quality and quantity of blastocyst formation compared to fully grown oocytes. This study aimed to increase the number of high-quality mature oocytes and improve their potential for ART applications in cloned and interspecies intracytoplasmic sperm injection (ICSI) embryos by utilising L-ascorbic acid (LAA) in pre in vitro maturation (pre-IVM) culture. First, oocytes isolated from SAFs were cultured with the duration of pre-IVM 0, 6, 8, 10 h and different concentrations of LAA to determine good conditions for oocyte maturation. Then, mature oocytes were assessed for their developmental competence through parthenogenesis, cloned and interspecies ICSI embryos. The results showed that 8-h pre-IVM with 50 μg/mL LAA improved the maturation rate and developmental competence of parthenogenetic and clone embryos, especially, improving the high blastocyst quality by increasing cell number and expression of histone acetylation at lysine 9 (H3K9ac). In addition, the culture process improved the nuclear reprogramming of somatic cells after nuclear transfer into mature oocytes, resulting in an increased hatching rate of cloned embryos. It also enhanced the activation and the pronuclear formation rate of Gaurus-Taurus zygotes. Overall, the established pre-IVM culture method enhanced the meiotic and developmental competence of embryos. This procedure opened hope for the preservation of endangered species and other applications.

The revolution in biology triggered by the different genome-editing tools has of course arrived to the research field of animal reproduction. Yeast meganucleases, zinc-finger nucleases, TALEN and, particularly, the several generations of CRISPR tools have landed in animal reproduction thereby providing novel strategies to optimize or modify some of the features and capabilities of the recipient animals. All these genome-editing proposals and activities are associated with ethical considerations regarding how those planned genome alterations might affect important animal welfare issues. The ethical dimension of all these genome editing must be seriously considered. Hence, all ethical aspects bound to any given genome-edited allele in animals should be discussed in order to ensure that we are maximizing benefits and reducing any potential risk or negative considerations of these modifications. In this review, I will summarize some of the experiments reported aiming to investigate or improve animal reproduction and I will address the ethics issues that should also be considered.