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141.
Grindflek E Meuwissen TH Aasmundstad T Hamland H Hansen MH Nome T Kent M Torjesen P Lien S 《Journal of animal science》2011,89(3):680-692
Boar taint is characterized by an unpleasant taste or odor in intact male pigs and is primarily attributed to increased concentrations of androstenone and skatole and to a lesser extent by increased indole. The boar taint compounds skatole and indole are produced by gut bacteria, metabolized in the liver, and stored in the fat tissue. Androstenone, on the other hand, is synthesized in the testis along with testosterone and estrogens, which are known to be important factors affecting fertility. The main goal of this study was to investigate the relationship between genetic factors involved in the primary boar taint compounds in an attempt to discover ways to reduce boar taint without decreasing fertility-related compounds. Heritabilities and genetic correlations between traits were estimated for compounds related to boar taint (androstenone, skatole, indole) and reproduction (testosterone, 17β-estradiol, and estrone sulfate). Heritabilities in the range of 0.47 to 0.67 were detected for androstenone concentrations in both fat and plasma, whereas those for skatole and indole were slightly less (0.27 to 0.41). The genetic correlations between androstenone in plasma and fat were extremely high (0.91 to 0.98) in Duroc and Landrace. In addition, genetic correlations between androstenone (both plasma and fat) and the other sex steroids (estrone sulfate, 17β-estradiol, and testosterone) were very high, in the range of 0.80 to 0.95. Furthermore, a genome-wide association study (GWA) and a combined linkage disequilibrium and linkage analysis (LDLA) were conducted on 1,533 purebred Landrace and 1,027 purebred Duroc to find genome regions involved in genetic control of the boar taint compounds androstenone, skatole, and indole, and sex hormones related to fertility traits. Up to 3,297 informative SNP markers were included for both breeds, including SNP from several boar taint candidate genes. From the GWA study, we found that altogether 27 regions were significant at a genome-wide level (P < 0.05) and an additional 7 regions were significant at a chromosomal level. From the LDLA study, 7 regions were significant on a genome-wide level and an additional 7 regions were significant at a chromosomal level. The most convincing associations were obtained in 6 regions affecting skatole and indole in fat on chromosomes 1, 2, 3, 7, 13, and 14, 1 region on chromosome 6 affecting androstenone in plasma only, and 5 regions on chromosomes 3, 4, 13, and 15 affecting androstenone, testosterone, and estrogens. 相似文献
142.
A retrospective analysis of the clinical and laboratory findings from 51 adult horses with chronic diarrhoea revealed that the most common conditions were larval cyathostomiasis (14 cases), idiopathic chronic colitis (nine cases) and alimentary lymphoma (five cases). Five animals had diarrhoea as a result of non-alimentary disease. A diagnosis was reached in 37 cases, but only 15 were made ante mortem. Among the 18 animals (35 per cent) which survived, there were five cases of larval cyathostomiasis, one case of colonic impaction and 12 cases were undiagnosed. The most frequent abnormalities detected in blood samples from the horses were neutrophilia, hypoalbuminaemia, hyperglobulinaemia and high alkaline phosphatase activity. Evidence of carbohydrate malabsorption was found in 16 of 28 cases in which oral glucose tolerance tests were performed. No diagnostic specificity was apparent in either the clinical signs or the laboratory findings. 相似文献
143.
144.
Ninomiya H Inomata T Ogihara K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(1):53-57
Uropathy associated with hydronephrosis was observed frequently in our male KK-Ay mouse colony during a long-term study of diabetes. The lesion occurred in 24 of the 31 KK-Ay male mice and accounted for the greatest number of spontaneous deaths among them. It was observed after 4 months of age and involved about hard plugs of altered seminal material resembling the seminal vesicle secretion. The plugs became impacted in the urethral bulb and the bladder. The penile anatomy, with its flexure, pressure on the urethra from the bulbocavernosus muscle, and the characteristic ability of the seminal fluid to easily coagulate to form the vaginal plug may have contributed to the lesion. Correlation between development of the uropathy and diabetes has not been established. 相似文献
145.
A D Ice A L Grant L K Clark T R Cline M E Einstein T G Martin M A Diekman 《American journal of veterinary research》1999,60(5):603-608
OBJECTIVE: To compare health and growth performance in barrows reared in all-in/all-out (AIAO) or continuous flow (CF) management systems. ANIMALS: 400 barrows. PROCEDURE: Barrows (approx 2 months old) were allotted to 4 replications (100 barrows each); barrows were housed in AIAO or CF rooms (10 pens/room), and 50 pigs/replicate received chlortetracycline (CTC, 110 mg/kg of feed). Barrows from each pen were slaughtered at 3, 4, 5, and 6 months old. RESULTS: Barrows in the AIAO room had greater total daily gain (TDG) and lean daily gain (LDG) than did barrows in the CF room. Addition of CTC did not improve TDG or LDG in either environment. Barrows in the AIAO room reached body weight of 104.5 kg in 169.7 days, compared with 177.3 days for barrows in the CF room. Feed-to-gain ratio was not affected by management or CTC. Lungs from barrows reared in AIAO facilities had a lower percentage of lesions than did lungs of barrows reared in CF facilities (1.74% vs 9.52%). Addition of CTC did not affect prevalence and extent of lung lesions. Extent of lung lesions was positively correlated with change in serum optical density (OD) to Mycoplasma hyopneumoniae (r = 0.35), but not with change in serum OD to Actinobacillus pleuropneumoniae. Lean growth and serum OD to M. hyopneumoniae and A. pleuropneumoniae were not correlated. CONCLUSIONS: Health and growth performance were better for barrows in an AIAO facility, compared with a CF facility, but addition of CTC to feed failed to enhance health or performance of barrows in either facility. 相似文献
146.
Five standardbred geldings were given 1 mg/kg bodyweight of frusemide by intramuscular injection to induce mild dehydration. After food and water deprivation overnight, the mean weight loss was 24.4 +/- 1.8 kg (5.5 per cent of bodyweight). The horses were then given an equivalent volume of an oral glucose-glycine-electrolyte solution by stomach tube. No more than 10 litres was given every 30 minutes until the calculated bodyweight loss had been replaced. Measurements made before, during and after the fluid administration included bodyweight, arterial blood haematocrit, PCO2, pH, standard bicarbonate, base excess and plasma concentrations of sodium, potassium, chloride, total protein, glucose, urea and creatinine. The final measurement was taken eight hours after the last dose of fluid and no food or water was offered to the horses during this time. Administration of the solution caused a rapid correction of the frusemide-induced dehydration and metabolic alkalosis. Absorption of the fluid from the gastrointestinal tract appeared to be very rapid because by 30 minutes after the last dose of the solution, plasma protein values were not significantly different from those before administration of frusemide. Plasma glucose concentrations became significantly increased for up to three hours after the fluid was given and an increase in creatinine and urea concentrations, which was observed after the administration of frusemide, was still evident at eight hours. The glucose-glycine-electrolyte solution was well retained, there being a mean bodyweight loss of 2.8 kg at three hours and 6.2 kg at eight hours after the last dose of fluid. 相似文献
147.
Mycosis of commercial Japanese quail, ducks and turkeys 总被引:1,自引:0,他引:1
148.
149.
J Miyagi K Tsuhako T Kinjo T Iwamasa Y Kamada T Kinju Y Koyanagi 《Veterinary pathology》1999,36(5):452-456
A 37-year-old female orangutan died at the zoological garden. Autopsy examination demonstrated severe coxsackievirus B4 myocarditis immunohistochemically as a cause of the death. Apoptosis of the cardiac muscle cells was observed using the TdT-mediated dUTP-biotin nick endo labeling method and was considered to play a role in the myocarditis. Congestion of the liver and both lungs due to cardiac failure was also observed. Coxsackievirus infection is found frequently in the Okinawan human population. The present orangutan's infection might have come from visitors who were allowed to go near the orangutan. Malignant tumors, severe suppurative infections, and intestinal parasite infections were not observed. Epstein-Barr virus DNA was detected in lymph nodes, but there was no Burkitt's lymphoma. 相似文献
150.
S. P. Gregory P. E. Holt T. J. Parkinson C. M. Wathes 《The Journal of small animal practice》1999,40(4):180-184
A study was undertaken to determine if the vagina might be a suitable site for the measurement of intra-abdominal pressure during cystometry in the bitch. The position of the cranial vagina and vaginal length were measured radiographically and the effects of spaying and urinary incontinence on these variables were evaluated in 30 continent and 30 incontinent bitches. The study used retrograde vaginourethrograms which had been obtained from animals used in a previous study. The cranial vagina was intra-abdominal on 36 of the vaginourethrograms, being least commonly intra-abdominal in incontinent bitches (11/30). Vaginal position was related linearly to vaginal length and continence status (P < 0.01), while its length was related to bodyweight (P < 0.01). Allowing for bodyweight, neutered animals had significantly shorter vaginas than entire bitches (P < 0.01). Measurement of intra-abdominal pressure with concomitant measurement of intravesical pressure is essential if accurate assessment of detrusor pressure is to be determined during cystometry. The vagina is unlikely to be a useful location from which to measure intra-abdominal pressure since any pressure-measuring catheter inserted into it may fall outside the abdominal pressure zone. This is particularly true of neutered and/or incontinent bitches, the groups in which urodynamic investigations of urinary incontinence are most frequently indicated. 相似文献