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131.
132.
The conformation of the urethra, the position of the bladder neck and the distance between the external urethral orifice and the cranial pubic brim were compared in 30 continent and 30 incontinent bitches with incompetence of the urethral sphincter mechanism, using the measurements made from vagino-urethrograms. The bladder neck was significantly (P less than 0.001) further caudal in incontinent dogs than in continent dogs. Its position was not affected by neutering and could not be explained by the degree of urethral curvature. The distance from the external urethral orifice to the cranial pubic brim was correlated (P less than 0.001) with bodyweight but was not significantly different in the continent and incontinent bitches. In neutered animals, the distance between the cranial pubic brim and the external urethral orifice was significantly (P less than 0.05) shorter than in entire animals.  相似文献   
133.
OBJECTIVE: To characterize the normal ultrasonographic appearance of the podotrochlear apparatus in horses by use of standardized measurements and identify soft tissue changes associated with navicular syndrome. DESIGN: Prospective study. ANIMALS: 7 clinically normal horses and 28 horses with navicular syndrome. PROCEDURE: The feasibility of identifying and measuring the soft tissue structures of the podotrochlear apparatus ultrasonographically via the transcuneal approach was assessed in 2 additional horses without navicular syndrome; both horses were euthanatized, and the structures identified ultrasonographically were confirmed at necropsy. Ultrasonographs were obtained in the study horses. Objective and subjective data were obtained to characterize ultrasonographic changes associated with navicular syndrome. RESULTS: Abnormalities of the flexor surface of the distal sesamoid (navicular) bone, the impar ligament, the distal digital annular ligament, deep digital flexor tendon (DDFT), and the podotrochlear (navicular) bursa were assessed via the transcuneal ultrasonographic approach. No significant differences were found between the measurements of the podotrochlear apparatus in normal horses and those with navicular syndrome; however, important subjective differences were detected ultrasonographically in horses with navicular syndrome. In horses with navicular syndrome, ultrasonographic findings were indicative of navicular bursitis, dystrophic mineralization of the DDFT and impar ligament, tendonitis and insertional tenopathy of the DDFT, desmitis of the impar ligament, and cortical changes in the flexor surface of the navicular bone. CONCLUSIONS AND CLINICAL RELEVANCE: Findings of ultrasonographic evaluation of the hoof appear to be useful in determining the cause of caudal heel pain and characterizing the components of navicular syndrome in horses.  相似文献   
134.
This article suggests a linear functional relationship model for comparing two sets of circular data subject to unobservable errors. Unlike the corresponding and relatively well-studied model for linear data, maximum likelihood estimation for this model is very complicated and no explicit solutions are possible. Using a numerical approximation, we are able to solve the likelihood equations approximately, and to obtain good approximations to the likelihood estimates of the parameters. The quality of our estimates and the feasibility of the estimation method are illustrated via simulation. By establishing a parallel with the model for linear data, we are able to explain the various problems occurring in the process of estimation and to substantiate our numerical results. The interest in the model arose in connection with the study of ocean wave data; an application to such data is also given.  相似文献   
135.
136.
We developed a method to derive optimum composite genotypes when the proportion of a specific breed (or combination of breeds) in the composite is constrained to a desired level. The method allows development of composites that balance net merit according to available parameters and reflects the production system and(or) risk preference, particularly when traits in the breeding objective do not represent all traits important for production. The method can also be used to evaluate the cost of constraining breed use. For example, when the true optimal composite is difficult to obtain in the time frame available to the producer, the predicted merit of the composite with breed proportion restricted to those that are obtainable in practice can be compared with the predicted merit of the true optimum composite. In a case study the method is used to optimize a tropical composite using Brahman, Charolais, and Belmont Red breeds. The proportion of Charolais is to be constrained to 50%. Using growth parameters from a tropical crossbreeding experiment, the unconstrained optimum composite was 32.5% Brahman, 11.1% Belmont Red, and 56.3% Charolais. When the proportion of Charolais in the composite was constrained to 50%, optimum proportions of Brahman and Belmont Red were 33.9% and 16.1% respectively. In the case study net merit (annualized profit per cow exposed, $), as defined by the growth parameters, was .2% less than that of the unconstrained optimum composite.  相似文献   
137.
Swinepox--skin disease with sporadic occurrence   总被引:1,自引:0,他引:1  
Swinepox virus infection results in an acute, mild or subclinical course and is characterised by typical poxvirus skin lesions in affected pigs. Additionally, sporadic vertical swinepox virus transmission leads to congenital generalised infection and subsequent abortion or stillbirth. The present report describes the occurrence of epidermal efflorescences in two piglets after intrauterine natural suipoxvirus infection. No clinical abnormalities of the gilt and littermates as well as in other pigs from this herd were present. One of the affected piglets was stillborn and submitted for necropsy, the other animal was alive at birth, but died 3 days later. Histologically, a proliferative to ulcerative dermatitis with epithelial ballooning degeneration and characteristic intracytoplasmatic inclusion bodies was observed. The pathomorphological and histopathological suspected diagnosis of a poxvirus infection was confirmed by electron microscopy. Furthermore, the agent was identified as suipoxvirus by polymerase chain reaction. As demonstrated here, obvious skin lesions in suipoxvirus infection leads to a suspected diagnosis in newborn piglets on macroscopic examination. However, further post mortem examinations, including electron microscopy as well as molecular techniques are essential for the identification of the aetiology and the exclusion of differential diagnoses. Because the disease only affected two pigs there was only a small economic loss. A valid diagnostic plays an important role in advising farmers and for herd health monitoring.  相似文献   
138.
Twenty-seven insecticides, including organochlorine, organophosphorus compounds and carbamates were tried for potentiation of the toxic effect of malathion. Carbaryl, diazinon, fenthion, gamma-BHC, parathion and tetrachlorvinphos potentiated the action of malathion. Fourteen insecticides gave additive effects while seven proved antagonistic. Insecticides which showed potentiation, were further tested by mixing with malathion in the ratios of 1:9, 3:7, 5:5, 7:3 and 9:1. All the five combinations in the six mixtures gave potentiating effects. Maximum potentiation of 17.6 times was observed in 1:9 combination of malathion and gamma-BHC. The proportions in which the insecticides were mixed had a pronounced effect on the toxic effect of malathion.  相似文献   
139.
The effect of a novel lairage environment on the ability of sheep to recover from 16 h of transport was investigated. Sheep were transported from grass paddocks to either novel outside paddocks or inside pens, and housed groups were transported to either familiar or novel inside pens. During transport, sheep from outside paddocks lay down less than those from inside pens. In sheep transported to inside pens, those from outside paddocks spent more time lying and spent less time eating; hay and water intakes during the first 12 h post-transport were lower than those previously kept inside. There was no obvious effect of a novel environment post-transport on blood biochemistry, suggesting that the lower post-transport feed and water intakes in a novel environment did not have a significant effect on the ability of the sheep to recover from the feed and water deprivation associated with transport.  相似文献   
140.
The objective of this study was to investigate epidemiological risk factors for porcine non-specific colitis (NSC). Forty-seven Scottish pig farms, with and without a clinical history of diarrhoea during the growing period (15-40 kg), were selected. The study included farm visits, clinical inspection of pigs, completion of farm management questionnaires, pathological tests into the cause of the diarrhoea and analysis of the non-starch polysaccharide (NSP) content of feeds. The results from 17 farms designated as NSC and 10 control farms suggest dietary associations with NSC. Farms with NSC fed diets with significantly higher levels of NSPs, especially containing the sugars glucose, arabinose and xylose. Few management factors were identified, although the high prevalence of infectious colitis reduced the power of the study.  相似文献   
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