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This study was conducted to identify and analyse the expression of gametogenesis‐associated genes and proteins in foetal and adult buffalo gonads of both the sexes. Relative quantification of the genes was determined by qPCR and Western blotting. Immunohistochemistry was also performed for various gametogenesis‐associated proteins in foetal and adult gonads of both the sexes. We observed significantly (p < 0.05) increased expression of primordial germ cell‐specific, meiotic as well as genes associated with oocyte maturation and development in foetal ovaries as compared to the adult ones. However, significantly (p < 0.05) increased expression of proteins associated with oocyte maturation like GDF9 and ZP4 was found in adult ovaries, indicating temporal regulation of mRNA translation during oogenesis. Meiotic genes showed significantly (p < 0.05) increased expression in adult testes as compared to foetal testes and ovaries, indicating onset of meiosis at a later stage in spermatogenesis. In general, the expression of primordial germ cell‐associated as well as meiotic genes was higher in adult testes, indicating the increased biological activity in the organ. Immunohistochemistry revealed localized expression of gametogenesis‐associated proteins in ovarian follicles and seminiferous tubules of testes, while the surrounding somatic tissues were devoid of these proteins. The study gives an understanding of the sequential and temporal events of gene expression as well as mRNA translation during male and female gametogenesis. It could also be concluded that follicles and seminiferous tubules are the functional units of the female and male gonads, respectively, and their function could be enhanced by appropriate chemical and genetic intervention of the somatic tissue immediately surrounding them. This assumes importance in the context that buffalo attains sexual maturity at an older age of 2–3 years and have smaller ovaries with lesser number of primordial follicles in comparison with cattle, which is suggested to be the main reason of their poor breeding performance.  相似文献   
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The left and right kidneys, ureters, urinary bladder and urethra of 29 female clinically healthy Saanen goats were examined via transcutaneous and transrectal ultrasonography. In order to establish reference values the examinations were performed using a 5.0 MHz linear transducer to scan the right caudal costal part of the abdominal wall, right and left dorsal flanks and right and left inguinal regions of standing goats. A 5.0 MHz intracavity probe was used for transrectal ultrasonographic examination of the urinary bladder and urethra. The kidneys were examined in longitudinal and cross section and assessed subjectively. They could usually be seen from the 12th intercostal space on the right side and dorsal right flank. The right kidney was 8.0 ± 0.67 cm long and the left was 8.4 ± 0.64 cm long. The ureters could not be visualized in any of the goats. The length of the urinary bladder was 5.1 ± 1.38 cm, and its largest cross-sectional diameter was 2.6 ± 1.01 cm. The urethra was seen in 23 goats and appeared as echogenic lines with no visible lumen. The transition from the neck of the bladder to the internal urethral orifice extended beyond the brim of the pelvis in only one goat.  相似文献   
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This study examined the effects of O2 concentration (5% vs 20%) during in vitro maturation (IVM), fertilization (IVF) and culture (IVC) or supplementation of IVM and IVC media with cysteamine (50 and 100 μm , respectively; IVM, IVF and IVC carried out in 20% O2), on blastocyst rate and relative mRNA abundance of some apoptosis‐related genes measured by real‐time qPCR in immature and in vitro‐matured buffalo oocytes and in embryos at 2‐, 4‐, 8‐ to 16‐cell, morula and blastocyst stages. The blastocyst rate was significantly higher (p < 0.05) while the percentage of TUNEL‐positive cells was significantly lower (p < 0.05) under 5% O2 than that under 20% O2. The mRNA expression of anti‐apoptotic genes BCL‐2 and MCL‐1 was significantly higher (p < 0.05) and that of pro‐apoptotic genes BAX and BID was lower (p < 0.05) under 5% O2 than that under 20% O2 concentration at many embryonic stages. Following cysteamine supplementation, the blastocyst rate and the relative mRNA abundance of BCL‐XL and MCL‐1 was significantly higher (p < 0.05) and that of BAX but not BID was lower (p < 0.05) at many stages of embryonic development, although it did not affect the percentage of TUNEL positive cells in the blastocysts significantly. The mRNA expression pattern of these genes during embryonic development was different in 5% vs 20% O2 groups and in cysteamine supplemented vs controls. At the 8‐ to 16‐cell stage, where developmental block occurs in buffalo, the relative mRNA abundance of BCL‐2 and MCL‐1 was highest under 5% O2 concentration and that of BAX and BID was highest (p < 0.05) under 20% O2 concentration. These results suggest that one of the mechanisms through which beneficial effects of low O2 concentration and cysteamine supplementation are mediated during in vitro embryo production is through an increase in the expression of anti‐apoptotic and a decrease in the expression of pro‐apoptotic genes.  相似文献   
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The objective of this study was to document the expression and localization of angiopoietin (ANGPT) family members comprising of angiopoietin (ANGPT1 and ANGPT2), and their receptors (Tie1 and Tie2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle, and the modulatory role of ANGPT1 and ANGPT2 alone or in combinations on progesterone (P4) secretion and mRNA expression of phosphotidylinositide‐3kinase‐protein kinase B (PI3K‐AKT), phosphoinositide‐dependent kinase (PDK), protein kinase B (AKT), Bcl2 associated death promoter (BAD), caspase 3 and von willebrand factor (vWF) in luteal cells obtained from midluteal phase (MLP) of oestrous cycle in buffalo. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors whereas, the P4 secretion was assessed by RIA. The mRNA and protein expression of ANGPT1 and Tie2 was maximum (p < .05) in mid luteal phase (MLP) of oestrous cycle. The ANGPT2 mRNA and protein expression was maximum (p < .05) in early luteal phase, decreased in MLP and again increased in late luteal phase of oestrous cycle. ANGPT family members were localized in luteal cells and endothelial cells with a stage specific immunoreactivity. P4 secretion was highest (p < .05) with 100 ng/ml at 72 hr when luteal cells were treated with either protein alone. The mRNA expression of PDK, AKT and vWF was highest (p < .05) and BAD along with caspase 3 were lowest (p < .05) at 100 ng/ml at 72 hr of incubation period, when cultured luteal cells were treated with either protein alone or in combination. To conclude, our study explores the steroidogenic potential of angiopoietins to promote P4 secretion, luteal cell survival and angiogenesis through an autocrine and paracrine actions in buffalo CL.  相似文献   
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ObjectiveTo compare racemic ketamine and S-ketamine as induction agents prior to isoflurane anaesthesia.Study designProspective, blinded, randomized experimental study.AnimalsThirty-one healthy adult goats weighing 39-86 kg.MethodsGoats were premedicated with xylazine (0.1 mg kg?1) intravenously (IV) given over 5 minutes. Each goat was assigned randomly to one of two treatments for IV anaesthetic induction: group RK (15 goats) racemic ketamine (3 mg kg?1) and group SK (16 goats) S-ketamine (1.5 mg kg?1). Time from end-injection to recumbency was measured and quality of anaesthetic induction and condition for endotracheal intubation were scored. Anaesthesia was maintained with isoflurane in oxygen for 90 minutes. Heart rate, invasive arterial blood pressure, oxygen saturation, temperature, end-tidal carbon dioxide and isoflurane were recorded every 5 minutes. Arterial blood samples were taken for analysis every 30 minutes. Recovery time to recurrence of swallowing reflex, to first head movement and to standing were recorded and recovery quality was scored. Two-way repeated measures anova, Mann-Whitney and a Mantel-Cox tests were used for statistical analysis as relevant with a significance level set at p < 0.05.ResultsInduction of anaesthesia was smooth and uneventful in all goats. There was no statistical difference between groups in any measured parameter. Side effects following anaesthetic induction included slight head or limb twitching, moving forward and backward, salivation and nystagmus but were minimal. Endotracheal intubation was achieved in all goats at first or second attempt. Recovery was uneventful on all occasions. All goats were quiet and needed only one or two attempts to stand.Conclusions and clinical relevanceS-ketamine at half the dose rate of racemic ketamine in goats sedated with xylazine and thereafter anaesthetised with isoflurane induces the same clinically measurable effects.  相似文献   
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Echocardiographic assessment of cardiac structures, dimensions, and mechanical function in goats is poorly documented. The goal of this study was to describe normal findings, establish normal values for two-dimensional (2DE) and M-mode (MME) echocardiography, and investigate the influence of general anaesthesia. Standardized 2DE and MME recordings were obtained on 22 healthy female Saanen goats (3.7 ± 1.1 years [mean ± SD], 60.2 ± 10.6?kg) awake (standing) and during isoflurane anesthesia (sternal recumbency). Cardiac dimensions and function were assessed and compared between treatments (awake vs. anaesthetized). Color Doppler imaging and saline contrast studies served to assess abnormal blood flow patterns. Post mortem examination was performed in a subset of 12 goats. Transthoracic echocardiography was feasible in all goats. Indices of LV systolic function proved to be significantly increased during general anesthesia. The membranous and occasionally echolucent appearance of the oval fossa suggested abnormal interatrial communication in 9 goats. Color Doppler imaging and saline contrast studies proved to be inaccurate to detect interatrial shunting of blood. Post mortem examination confirmed small persistent foramen ovale in only 3 out of 7 goats, in which it had been suspected on echocardiography.  相似文献   
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This retrospective case study aims to evaluate the accuracy of menace response, response to nasal stimulation and proprioceptive placing in diagnosing forebrain lesion in dogs. A total of 145 client-owned dogs investigated by magnetic resonance imaging study of the brain between December 2017 and June 2019 were evaluated. Seventy-one dogs with no magnetic resonance imaging-detectable intracranial and significant cerebrospinal fluid abnormality or recent history of seizure (<48 h) served as controls. Binary regression analysis was performed to determine the sensitivity, specificity and likelihood ratios of each selected test. Older age at presentation was a significant risk factor for the presence of a forebrain lesion. Menace (62.5%) and proprioceptive deficits (40.5%) were common findings in all dogs. They were also significantly associated with the presence of forebrain abnormality. Moreover, they were more sensitive (77.3% and 82.2%, respectively) and specific (50.0% and 62.5%, respectively) when applied to dogs aged 6 years or older. Nonetheless, all of these tests' likelihood ratios, and thus reliability are poor. These neurological tests are commonly employed for diagnosing forebrain disease in dogs, yet are not highly accurate in diagnosing forebrain abnormality. Clinicians should interpret these clinical test results along with the patient history when designing a diagnostic plan.  相似文献   
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