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741.
742.
ABSTRACT Thirty-nine isolates of Fusarium oxysporum were collected from tomato plants displaying wilt symptoms in a field in California 2 years after F. oxysporum f. sp. lycopersici race 3 was first observed at that location. These and other isolates of F. oxysporum f. sp. lycopersici were characterized by pathogenicity, race, and vegetative compatibility group (VCG). Of the 39 California isolates, 22 were in VCG 0030, 11 in VCG 0031, and six in the newly described VCG 0035. Among the isolates in VCG 0030, 13 were race 3, and nine were race 2. Of the isolates in VCG 0031, seven were race 2, one was race 1, and three were nonpathogenic to tomato. All six isolates in VCG 0035 were race 2. Restriction fragment length polymorphisms (RFLPs) and sequencing of the intergenic spacer (IGS) region of rDNA identified five IGS RFLP haplotypes, which coincided with VCGs, among 60 isolates of F. oxysporum from tomato. Five race 3 isolates from California were of the same genomic DNA RFLP haplotype as a race 2 isolate from the same location, and all 13 race 3 isolates clustered together into a subgroup in the neighbor joining tree. Collective evidence suggests that race 3 in California originated from the local race 2 population.  相似文献   
743.
Nutritional myopathy in goats   总被引:1,自引:0,他引:1  
A nutritional myopathy in unweaned fibre goats aged 2 to 4 mths is described in 3 flocks from the tablelands of New South Wales. Clinically affected animals were illthrifty and in circulatory failure prior to being found dead. At necropsy, there was pronounced ascites, pulmonary congestion and marked mottling of the liver. Chalky white streaks and patches were obvious in the myocardium, particularly in the right ventricular wall. Skeletal muscles varied from grossly normal to generally pale. Histologically, the myocardium exhibited areas of severe acute myonecrosis with mineralisation and adjoining areas of phagocytosis and fibrosis. In 2 of 3 flocks, some skeletal muscles showed a mild subacute myopathy. Marked hepatic congestion extended to periacinar haemorrhage and necrosis in some areas. Dietary imbalances of selenium, vitamin E and polyunsatured fatty acids were probable factors in the pathogenesis of the condition.  相似文献   
744.
SUMMARY Suckling and yearling calves were surgically castrated and one half of each group implanted with 36 mg zeranol at time of castration. Both treated and control cattle of each class were maintained as a group and evaluated for swelling of the scrotum, inflammation and healing, plasma prostaglandin levels and weight gain. Swelling and inflammation of the scrotum were less in treated suckling calves than in controls at both 7 and 14 d after castration, though this difference was not statistically significant. In yearlings at 7 d after castration, treated cattle had more swelling than controls; however at 14 d, treated cattle had less swelling and inflammation with only one treated yearling having an open scrotal wound versus 6 (P <.03) in the control group. Plasma prostaglandin levels as indicated by plasma malondialdehyde increased from d 0 to 14; however no significant treatment differences were observed for either age group. Suckling calves treated with zeranol gained 9.79 kg more (P <.03) than non-treated calves during the 97 d of trial while the yearlings treated with zeranol gained 16.78 kg more (P <.01) than controls during 102 d. It is concluded from the increased growth and reduced scrotal swelling and inflammation in treated cattle that zeranol implantation could possibly have a beneficial effect in improving the healing process after castration.  相似文献   
745.
The following results were obtained from studies into the behaviour of blood glucose in 439 piglets: -The first experimental group included 48 piglets exposed to follow-up checks in the first ten days of age. Glucose values prior to the first intake of foremilk were higher than those measured afterwards in ten animals (20.8 per cent). The second experimental group included 391 piglets tested under production conditions, and a result identical to the one above was recorded from 48 animals (12.3 per cent). The conclusion is that rise of blood glucose does not take place in all piglets after the first intake of foremilk. -Blood glucose concentrations were found to go up discontinuously up to the tenth day of age, depending on birth weight and feed intake as well as on glycolytical and gluconeogenetical capacities. -Average glucose values between 50.23 and 67.37 mg/100 ml plasma were recorded from newborn piglets prior to first foremilk intake in four groups differentiated by weights a birth between 800 g and 2,200 g. A relationship was statistically secured between blood glucose concentration and birth weight of newborn piglets. The correlation factor appeared to depend on the weight at birth.  相似文献   
746.
747.
A combination of oestriol and testosterone oenanthate was tried in 14 different indications on 110 dogs and 5 cats of both sexes. Two formulations were used, containing in 1 ml either 0.15 mg oestriol and 2.25 mg testosterone or 1.15 mg of the former and 2.25 mg of the latter. Dosage was 0.2 ml per kg body weight, by i/m injection. The criterion for success was the degree of functional restitution, without taking into account pathological changes, which were generally unaffected. Good or very good results were obtained in hip dysplasia, arthitis and patellar luxation. None of the 50 bitches treated showed signs of oestrus or irregularities in the cycle. The formulation containing the lower drug concentration seemed to give the best therapeutic results.  相似文献   
748.
749.
The aim of the present study was to assess follicular and oocyte development in the same gilts during three phases of their reproductive life [prepuberal gilts (PP; 6.0 months of age), puberal gilts (P; 9.5 months of age) and primiparous sows (S)]. Follicular development was stimulated by the injection of 1,000 IU of equine chorionic gonadotropin (eCG) followed by 500 IU of human chorionic gonadotropin (hCG) 72 h later. Cumulus-oocyte-complexes (COCs) were recovered by endoscopic ovum pick up/aspiration from preovulatory follicles of the left ovary, and the follicular fluid (FF) from the right ovary was collected 34 h after the hCG treatment by endoscopy. Altogether, 19 pigs were used in the PP and P trials and 12 in the S trial. From the left ovaries, 168, 190 and 82 follicles were aspirated and 106, 125 and 42 COCs, respectively, were recovered (recovery rate 61 +/- 27, 63 +/- 21 and 53 +/- 22%, respectively). The mean number of follicles was greater in the P phase than in the PP phase (19.7 +/- 6.8 vs. 15.7 +/- 6.8; p=0.06) and S phases (14.2 +/- 4.0; p<0.05). More uniform oocytes with an expanded cumulus were aspirated in the P and PP phases than in the S phase (90 and 78 vs. 46%; p<0.05). Furthermore, the meiotic configuration in oocytes (T I/M II stage) differed between the three phases (56 and 62 vs. 0%; p<0.05). Progesterone (P4) levels in FF decreased from 590.0 +/- 333.6 (PP) to 249.1 +/- 72.6 (P) and 161.4 +/- 75.2 ng/ml (S) (p<0.05). Estradiol-17beta (E2) levels differed between PP and P gilts and S sows (9.3 +/- 2.9, 21.9 +/- 10.6 and 94.0 +/- 15.9 pg/ml, respectively; p<0.05), and the P4/E2 ratio was 72, 15 and 5, respectively. These results indicate differences in follicular and oocyte development between the reproductive phases investigated. Puberal gilts should preferably be used in IVF and breeding programs. The lower reproductive potential of primiparous sows must be taken into consideration in breeding. Any prediction of lifetime performance based on individual ovarian reactions of prepuberal gilts is unreliable.  相似文献   
750.
Four horses were examined because of chronic forelimb lameness. In all horses, the cause of the lameness was localized to the metacarpus by means of physical examination and diagnostic anesthesia, and radiography of the affected limb revealed a small exostosis of the second metacarpal bone. Magnetic resonance imaging revealed suspensory desmitis in the region of this exostosis in all 4 horses. In addition, an abnormal area of low signal intensity, suggestive of an adhesion, was seen between the exostosis and the suspensory ligament. In all horses, an adhesion between the suspensory ligament and the exostosis on the second metacarpal bone was identified and transected at surgery, and the exostosis and distal portion of the second metacarpal bone were removed. All horses were able to return to their previous athletic use following a 6-month rest and rehabilitation program for treatment of the suspensory desmitis. Findings in these horses suggest that adhesions between the suspensory ligament and an exostosis of the second metacarpal bone may be a cause of chronic or recurrent forelimb lameness in horses.  相似文献   
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