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101.
Puberty is a stage of sexual development determined by the interaction of environmental factors and genetic mechanisms. Among them, thyroid function plays a key role in sexual development and spermatogenic function and is under the control of several genes, including the well‐described thyroglobulin gene (TG). Previous reports have shown genetic association between thyroid function and selected single nucleotide polymorphisms (SNPs) in taurine cattle. Therefore, the identification of genetic mechanisms involved in the regulation of this trait can assist with the selection for early pubertal bulls, thus improving genetic progress in livestock breeding. The aim of this study was to validate the association between TG SNPs and age at puberty in zebuine bulls. Three SNPs (rs110406764, rs109662686, rs109057985) were genotyped in 159 Guzerat animals using SEQUENOM technology. Results showed a significant association (< .05) between the studied SNPs and puberty age, in agreement with our previous reports in a taurine breed. Interestingly, allele frequencies were different from those already reported, being GAT the most favourable allele for age at puberty in Guzerat (94.4 days lower). Overall, our findings corroborate previous reports and reinforce the importance of genetic influence in the regulation of sexual development and puberty through a thyroid pathway in zebuine cattle.  相似文献   
102.
Objective To determine the effect of a long-acting local anaesthetic on the plasma cortisol response in calves dehorned using a scoop.
Design A physiological study with controls.
Procedure Seventy female calves, 3 to 4 months old, were divided into seven groups and dehorned by scoop with or without a long acting local anaesthetic (bupivacaine) which provides local anaesthesia for 3 to 4 h. In some treatment groups the local anaesthetic was given a second time, after 4 h, to give 8 h of anaesthesia. Blood samples were taken before and for 9 h after treatment and plasma cortisol concentrations were measured.
Results Scoop dehorning caused a marked rise in plasma cortisol concentration, which returned to pre-dehorning values after 7 h. The cortisol concentrations of calves given bupiva-caine were similar to those of control animals for 4 h after dehorning, but then a significant and protracted rise occurred, with concentrations returning to pretreatment values at about 9 h after dehorning. In calves given a second treatment of bupivacaine 4 h after dehorning, the plasma cortisol concentration remained similar to control values for 8 h after dehorning but then increased sharply.
Conclusions During its period of activity long-acting local anaesthetic prevented the rise usually seen after scoop dehorning in plasma cortisol concentrations; by inference it also alleviated the pain-induced distress caused by this procedure. However, when its effects had worn off the plasma cortisol values rose sharply indicating that animals still experienced pain-induced distress despite local anaesthetic being administered.  相似文献   
103.
Regucalcin (RGN) is a calcium‐regulating, anti‐apoptotic, antioxidative and antiproliferative multifunctional protein predominantly seen in liver and kidney. All these functions are very crucial during spermatogenesis and sperm maturation process until fertilization of the ovum. Although many studies have reported the wide distribution of regucalcin in the male reproductive tract of the rat, human and bovine, its presence in spermatozoa is yet to be demonstrated wherein calcium has a pivotal role in the transport, capacitation, acrosomal reaction and further fusion with ova. Here, we detected the expression of regucalcin mRNA and protein in buffalo spermatozoa using real‐time PCR and Western blot, respectively. The study detected two new regucalcin isoforms of 44 kDa and 48 kDa size along with the reported 34‐kDa, 28‐kDa and 24‐kDa isoforms, wherein the 34‐kDa isoform was found to be membrane associated in spermatozoa. Further, immunocytochemistry study localized the regucalcin protein in the acrosomal region of the caudal and ejaculated buffalo spermatozoa while it was detected in both cytoplasm and acrosomal region of testicular spermatozoa. This discovery of RGN in spermatozoa and localization in the acrosomal region will help to focus researchers to see its role in calcium‐related functions like capacitation, acrosomal reaction and membrane fusion. Overall, regucalcin may be a new fertility marker in buffalo and can be utilized for infertility treatments.  相似文献   
104.
Retrospective analysis of records, from July 1987 to June 1991, of 1140 inspections of slaughtered pigs from 154 swine herds in the Pig Health Monitoring Scheme of South Australia was conducted to evaluate patterns of variation in the prevalence and severity of skin lesions typical of sarcoptic mange. An increase in the severity of sarcoptic mange in winter and spring was observed. There was a substantial reduction in the severity of mange over the period of monitoring. These observations support the role of monitoring at slaughter in the management of endemic disease. They provide some basis for refining control programs for mange to improve cost-effectiveness.  相似文献   
105.
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107.

Objective

To investigate the clinical and physiological effects of intravenous (IV) alfaxalone alone or in combination with buprenorphine, butorphanol or tramadol premedication in marmosets.

Study design

Prospective, randomized, blinded, crossover design.

Animals

Nine healthy marmosets (391 ± 48 g, 3.7 ± 2.2 years old).

Methods

Meloxicam 0.20 mg kg?1 subcutaneously, atropine 0.05 mg kg?1 intramuscularly (IM) and either buprenorphine 20 μg kg?1 IM (BUP-A), butorphanol 0.2 mg kg?1 IM (BUT-A), tramadol 1.5 mg kg?1 IM (TRA-A) or no additional drug (control) were administered to all marmosets as premedication. After 1 hour, anaesthesia was induced with 16 mg kg?1 alfaxalone IV. All animals received all protocols. The order of protocol allocation was randomized with a minimum 28 day wash-out period. During anaesthesia, respiratory and pulse rates, rectal temperature, haemoglobin oxygen saturation, arterial blood pressure, palpebral and pedal withdrawal reflexes and degree of muscle relaxation were assessed and recorded every 5 minutes. Quality of induction and recovery were assessed. Duration of induction, immobilization and recovery were recorded. Blood samples were analysed for aspartate aminotransferase, creatine kinase and lactate dehydrogenase concentrations. The protocols were compared using paired t tests, Wilcoxon's signed-rank test with Bonferroni's corrections and linear mixed effect models where appropriate.

Results

Out of nine animals, apnoea was noted in eight animals administered protocol BUP-A and two animals administered protocol BUT-A. With TRA-A and control protocols, apnoea was not observed. No other significant differences in any of the parameters were found; however, low arterial blood pressures and hypoxia occurred in TRA-A.

Conclusions and clinical relevance

Our study employing different premedications suggests that the previously published dose of 16 mg kg?1 alfaxalone is too high when used with premedication because we found a high incidence of complications including apnoea (BUP-A), hypotension and hypoxaemia (TRA-A). Appropriate monitoring and countermeasures are recommended.  相似文献   
108.
Abstract

AIMS: To objectively compare measures of bone healing, using computed tomography (CT) in dogs following bilateral tibial tuberosity advancement (TTA), between tibiae treated with and without autogenous cancellous bone grafts.

METHODS: Ten dogs with bilateral cranial cruciate ligament disease requiring surgical stabilisation were prospectively recruited to undergo single-session bilateral TTA, with only one, randomly assigned, tibia receiving bone graft in the osteotomy deficit. Bone healing at the osteotomy site was assessed using CT performed 38–70 days post-operatively. CT images were evaluated using both objective measurements of osseous bridging and subjective evaluation by six radiologists. Repeated measures ANOVA was used to compare the objective outcomes between the grafted and non-grafted tibiae.

RESULTS: The mean percentage of the osteotomy deficit bridged at the lateral cortex was greater in grafted (77.6, SD 35.2%) compared to non-grafted (63.0, SD 36.5%) tibiae (p=0.001), but did not differ at the medial cortex (p=0.1). The mean minimum callus width was greater in grafted (7.2, SD 3.3 mm) compared to non-grafted (3.6, SD 2.9 mm) tibiae (p<0.001). There was no difference in mean attenuation (measured in Hounsfield units) of the callus between grafted and non-grafted tibiae (p=0.5). The grafted tibia was deemed to have superior bone healing in 50/60 subjective assessments made by radiologists.

CONCLUSIONS: Superior osseous bridging was detected by CT analysis following TTA using autogenous cancellous bone grafts compared with no graft. This was shown by greater bridging percentage at the lateral cortex and formation of a broader callus. Qualitative assessments made by six radiologists also supported the conclusion that bone healing was improved by use of autogenous cancellous bone graft. CT was a useful method for assessing evidence of bone healing following TTA.

CLINICAL RELEVANCE: These findings justify the application of autogenous cancellous bone graft to augment healing following TTA in dogs.  相似文献   
109.
Abstract

CASE HISTORIES: Three dogs, aged between 11 and 20 weeks, were presented with unilateral forelimb lameness, with an associated bony prominence on the lateral elbow.

CLINICAL FINDINGS AND DIAGNOSIS: Radiographs revealed a caudolateral luxation of the radial head in all cases, consistent with a diagnosis of suspected congenital luxation of the radial head. Surgical reduction and stabilisation involved open reduction of the radial head, and in two cases the use of a trans articular pin.

CLINICAL RELEVANCE: Congenital luxation of the radial head is an uncommon condition that has conflicting reports in the literature regarding its cause, heritability, breed predisposition, treatment and prognosis. The three cases here occurred in young dogs of English Bull Terrier, Jack Russell Terrier, and Staffordshire Bull Terrier breeds. Surgical reduction and stabilisation provided successful outcomes, in all cases. Only six cases of congenital luxation of the radial head managed surgically have previously been reported in the literature.  相似文献   
110.
Extract

A 6-year-old Thoroughbred-cross gelding was presented with ulcerative coronitis and sloughing of chestnuts and ergots. The horse was mildly lame and its faeces were soft and formless. Laboratory findings included a mild eosinophilia, mild hyperglobuli-naemia and a marked elevation of gamma glutamyl transferase and glutamate dehydrogenase. There was a general deterioration of the horse's condition over a 3-week period and the dermatitis became generalised and the diarrhoea severe. It was euthanised. At necropsy, the pancreas was pale, multinodular and firm. The liver had a lobular appearance and there was generalised thickening of the descending colon. Histologically, there was a marked, predominantly eosinophilic infiltrate of the pancreas, liver and colon. There was a superficial and deep perivascular dermatitis of the coronet, characterised by dense infiltrates of eosinophils in association with marked acanthosis and hyperkeratosis. The combination of clinical findings, haematology, serum biochemistry and gross changes in conjunction with the histology confirmed MEED. The aetiology of MEED has not been established.  相似文献   
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