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181.
182.
Abstract

A Short Communication was published in the October 2002 issue of the New Zealand Veterinary Journal entitled “An investigation of the safety of oral calcium formate in dairy cows using clinical, biochemical and histopathological parameters” (McIntyre and Weston 2002 McIntyre, LH and Weston, SJ. 2002. An investigation of the safety of oral calcium formate in dairy cows using clinical, biochemical and histopathological parameters. New Zealand Veterinary Journal, 50: 195198. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar]). It appeared to be comparing results directly withthose of a prior communication (Scott and Van Wijk 2000 Scott, DJ and Van Wijk, N. 2000. Comparison in dairy cattle of mucosal toxicity of calcium formate and calcium chloride in oil. New Zealand Veterinary Journal, 48: 2426. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar]).  相似文献   
183.
Brucellosis is a major constraint for small-scale goat farming systems in Mexico. This study estimated the prevalence of testing positive to brucellosis and identified and quantified risk factors in goats from small-scale farms of Michoacán that had participated in a brucellosis campaign (i.e. vaccination, serological testing, culling and awareness) and of Jalisco that had negligible brucellosis campaign participation. A cross-sectional serological survey was conducted among 1,713 goats of 83 flocks. The prevalence of testing positive to brucellosis was higher (38 %) in Jalisco than in Michoacán (11 %). Logistic regression analysis indicated that goats from Michoacán had lower odds to test positive for brucellosis (odds ratio (OR)?=?0.32, 95 % confidence interval (CI) 0.21–0.48) compared to goats from Jalisco. Goats in zero-grazing systems had lower odds than goats in grazing systems (OR?=?0.22, 95 % CI 0.09–0.57). When goats were kept in pens with low density (0.002 to 0.22 goat/m2), odds was lower (OR?=?0.44, 95 % CI 0.28–0.67) compared to goats kept in pens with higher density (0.23 to 1 goat/m2). Odds was higher for testing positive when farmers bought goats from goat traders (OR?=?1.82, 95 % CI 1.15–2.87) compared to farmers who did not. If scavenger poultry had access to goat pens, the odds was half (OR?=?0.52, 95 % CI 0.33–0.83) of those where poultry had no access. Regular disinfection of the pen reduced the odds (OR?=?0.66, 95 % CI 0.44–0.99) compared to where disinfection was not regular. The brucellosis control campaign was effective in reducing brucellosis seropositivity.  相似文献   
184.
To ensure sufficient numbers of pregnant females, particularly at hotter times of the year, hormonal induction of gilt oestrus may be necessary. However, the gilt oestrus and ovulation responses to gonadotrophin treatment have often proven unpredictable. The objective of this study was to examine possible reasons for this unpredictability. Prepubertal gilts (approximately 150 days of age, n = 63) were assigned to one of three treatments: injection of 300 IU hCG (n = 15); pre-treatment with 100 mg FSH in polyvinylpyrrolidinone administered as 2 × 50 mg injections 24 h apart, followed by 600 IU eCG at 24 h after the second FSH injection (n = 23); or FSH pre-treatment as above followed by 300 IU hCG at 24 h after the second FSH injection (n = 25). To facilitate oestrus detection, gilts were exposed to a mature boar for 15 min daily for 7 days. Blood samples were obtained on the day of eCG or hCG injection and again 10 days later and gilt ovulation responses determined based on elevated progesterone concentrations. The oestrus responses by 7 days were 6.7%, 17.5% and 64.0% for gilts treated with hCG, FSH + eCG and FSH + hCG, respectively (p < 0.001). The oestrous gilt receiving hCG alone and one oestrous FSH + hCG gilt did not ovulate, all other oestrous gilts ovulated. A further two anoestrous FSH + eCG-treated gilts ovulated. These data suggest that FSH pre-treatment facilitated the development of ovarian follicles to the point where they became responsive to hCG, but had little effect on the response to eCG.  相似文献   
185.
186.
Chronic esophagitis due to gastroesophageal reflux (GER) is rarely reported in the cat. This paper describes the clinical signs and diagnostic findings, including radiographic, endoscopic, and histopathological abnormalities, in three young, purebred, male cats with esophagitis presumed to be secondary to GER. Clinical signs included regurgitation, dysphagia, and weight loss. Contrast radiography revealed GER, esophageal dilatation, and decreased motility. Endoscopy showed hyperemia, increased vascularity, ulcers, erosion, and an abnormal lower esophageal sphincter. Histopathological lesions included squamous hyperplasia and dysplasia, erosions, ulcers, and an inflammatory infiltrate of lymphocytes, plasma cells, and neutrophils. Long-term follow-up demonstrated progression of the disease in two of the cats.  相似文献   
187.
采用紫外分光光度法测定氧氟沙星油剂注射液的含量,选择氯仿与无水甲醇作溶剂,于220~400 nm间扫描,在299 nm波长处有最大吸收峰,辅料无干扰.实验结果表明,氧氟沙星浓度在0.5~2.5 μg/mL范围内,其吸收度与浓度呈良好的线性关系.线性方程为A=-0.86×10-2 4.75×10-1 C,r=0.999 9,平均回收率为100.3%,RSD=0.36%(n=5).  相似文献   
188.
OBJECTIVE: To identify factors associated with outcome of cats with nonvisceral soft tissue sarcomas treated with surgery alone. DESIGN: Retrospective study. ANIMALS: 42 cats. PROCEDURE: Medical records were reviewed for clinically relevant data, and histologic samples were examined. Follow-up information was obtained by means of physical examination or through telephone conversations with referring veterinarians and owners. The Kaplan-Meier method was used to construct survival curves. RESULTS: Median survival time was 608 days (range, 85 to 2,291 days), although 24 cats were still alive at the time of the study. Tumor size (ie, diameter) and histologic type were significantly associated with survival time. Median survival time was significantly longer in cats with tumors that were < 2 cm in diameter, compared with cats in which tumors were > 2 cm. Median survival times for cats with a fibrosarcoma or nerve sheath tumor were significantly longer than median time for cats with a malignant fibrous histiocytoma. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that tumor size and type are significantly associated with survival time in cats with nonvisceral soft tissue tumors.  相似文献   
189.
OBJECTIVE: To assess use of thoracoscopy to determine causes of pleural effusion in dogs and cats. DESIGN: Retrospective study. ANIMALS: 15 dogs and 3 cats with pleural effusion. PROCEDURE: Medical records were reviewed from 1998 to 2001 for dogs and cats that had exploratory thoracoscopy, biopsy, and histologic analysis to determine the etiology of pleural effusion. Intraoperative and postoperative complications were recorded. Surgical biopsy specimens were evaluated for quantity and quality for providing a histologic diagnosis. RESULTS: Biopsy specimens were deemed adequate in quantity and quality to render a histologic diagnosis in all animals. Etiology of the effusion was neoplasia in 8 animals and non-neoplastic pleuritis in 10 animals. Median survival time of animals with neoplasia was 15 days, whereas those with inflammatory diseases had median survival time of > 785 days. Postoperative pneumothorax was encountered in 2 animals subsequent to pulmonary biopsy. No other major complications were recorded. CONCLUSIONS AND CLINICAL RELEVANCE: Thoracoscopy is a diagnostic option that provides excellent viewing of intrathoracic structures and adequate biopsy specimens with minimal complications. This technique provides a less invasive alternative to thoracotomy for evaluating the etiology of pleural effusion.  相似文献   
190.
Frozen-thawed (FT) boar sperm have a reduced fertile life, due in part to a capacitation-like status induced by cooling. Reversal of this cryocapacitation in vitro by exposure to boar seminal plasma (SP) has been demonstrated. The objective of these studies was to determine the effect of SP on the ability of FT sperm to create an oviductal sperm reservoir following artificial insemination (AI). In Experiment one, 35 pre-pubertal gilts were injected (IM) with 400 IU eCG plus 200 IU hCG to induce oestrus. At detection of oestrus, gilts were inseminated with 3 x 10(9) live sperm, either fresh (FS; n = 13), FT (n = 10), or FT supplemented with 10% v/v SP (n = 12). Gilts were killed 8 h later, their reproductive tracts recovered and the uterotubal junctions (UTJs) flushed to recover sperm. Fewer (p < 0.01) sperm were recovered following FT, compared to FS, inseminations, and there was no evident effect of SP. In Experiment two, 30 pre-pubertal gilts received IM injections of 1000 IU eCG followed by 5 mg pLH 80 h later to control time of ovulation. Gilts were inseminated with 3 x 10(9) live FS sperm (n = 6), FT sperm (n = 15) or FT sperm plus 10% SP (n = 9) at 12 h before ovulation and then sacrificed 8 h later. The UTJs were dissected and flushed for sperm recovery. Fewest (p < 0.001) sperm were recovered following FT insemination and there was no evident effect of SP. These data demonstrate that the size of the sperm reservoir is markedly reduced in gilts inseminated with FT sperm. However, the lack of effect of SP suggested that either it did not reverse cryocapacitation or that such a reversal does not impact the in vivo ability to create a sperm reservoir.  相似文献   
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