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921.
Four methods of predicting breeding values for carcass gain are compared: “regressed” least squares (RLSQ), mixed model (MM), mixed model with relationships among sires considered (MMR) and contemporary-comparison (CC). Very small changes in the ranking of the sires were observed from one method to another (rank correlations > 0.96). Consideration of the relationships among the sires or deleting the breed-group factor from the model did not lead to substantially different breeding values. The good correspondence of the predictors is mainly due to the well balanced distribution of the progeny over herds. 相似文献
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925.
Rapid detection of Aujeszky's disease (pseudorabies) virus infection of pigs by direct filter hybridisation of nasal and tonsillar specimens 总被引:1,自引:0,他引:1
A direct filter hybridisation method has been developed to diagnose acute Aujeszky's disease in live pigs. The advantages of the method are easy, fast sample processing; no DNA-purification is needed, and the hybridisation itself is simplified. The direct filter hybridisation method has been tested on pseudorabies virus infected cultured cells, experimentally infected pigs and on specimens from an outbreak of Aujeszky's disease. Virus isolation and filter hybridisation gave comparable results, indicating that the direct filter hybridisation method is a good tool for rapid diagnosis. It is independent of cell culture facilities and the disease can be diagnosed in live animals within 15 hours. 相似文献
926.
Phage typing was performed on 86 strains of Staphylococcus aureus and 25 strains of Staphylococcus intermedius from rooks and gulls with human, bovine, chicken and canine phages. Eighty per cent of the S aureus strains and 64 per cent of the S intermedius strains were typable. The S aureus biotype D strains of rook origin were specifically lysed at routine test dilution (RTD) by chicken phages from groups I or I + IV, by human phages belonging to groups I and M, and partly by canine phage 58. The other rook and gull S aureus strains did not show characteristic phage patterns. The S intermedius strains isolated from both species of birds could be typed only with canine phages and this correlated with their classification into biotypes. All the biotype 1 strains tested but only two of 12 biotype 2 strains were lysed with canine phages at RTD. 相似文献
927.
Studies were made with a total of 272 fattening pigs. Iodine deficiency both in rations of soya bean meal and rape seed meal increased the weight of the thyroid gland and the height of the epithelium cells and significantly reduced the T4 and T3 level in the serum. Iodine supplements to the rape seed meal rations distinctly diminished the goitrogenic effect, did not, however, cancel it out. Stage of goiter and depression of consumption were--different shown by the T3 and T4 level in the serum. Highly significant relations were calculated between live weight gain, weight and the height of the epithelium cells on the one hand and the T4 level in the serum on the other. Iodine supplementations of rations without thyrostatic components should amount to greater than or equal to 0.1 mg/kg. Iodine supplementations of 0.5 mg/kg feed are at present recommended to rations with rape seed meal quotas of less than 8%. 相似文献
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929.
A follow up study was performed in 412 spayed bitches in order to determine the incidence of urinary incontinence. The period between the operation being performed and the survey being made varied between 3 and 10 years. 83 animals (20.1%) were incontinent independent of the surgical procedure (ovariectomy versus ovariohysterectomy). The onset of incontinence varied between immediately to 12 years with an average period of 2.9 years after surgery. 57 of these incontinent bitches were treated with ephedrine or estrogen. In 73.7% a good response was achieved with ephedrine and a further 23.7% showed some improvement. Generally ephedrine was more successful than estrogen in the treatment of incontinence. There appears to be a strong connection between body weight and the incidence of incontinence. Of bitches with a body weight of less than 20 kg only 9.3% were incontinent. Whereas in bitches with a body weight of more than 20 kg the incidence was 30.9%. Of the breeds Boxers showed a high incidence of incontinence (65%) while breeds such as German Shepherds (10.6%) or Dachshunds (11.1%) showed a low incidence in relation to the average incidence rate (20.1%). 相似文献
930.
The dynamics of hematological, protein, mineral and electrolytic profile was examined clinically in nine calves when the hemoconcentration was induced experimentally. The hemoconcentration occurred after diarrhea caused by the per os application of 12 g saccharose per one kg of live weight. The hemoconcentration culminated six hours after application. The calves where the hemoconcentration did not exceed the critical value were included in the first group, and the calves with the extreme hemoconcentration values in the other group. In the first group (with the increasing hemoconcentration degree), a statistically significant increase was found in the values of hematocrit, erythrocytes, hemoglobin, total protein in blood serum and total immunoglobins and a statistically insignificant increase in the levels of leucocytes, inorganic phosphorus, serum calcium and sodium. Serum potassium and magnesium showed the inverse dynamics, i. e. the decrease. In the second group (with the extreme hemoconcentration), hyperkalemia and slight hypermagnesemia were identified, while the other parameters showed deviations similar to those observed in the first group. After the rehydration of animals by a preparation without any influence on the studied parameters, the hemoconcentration and the parameters under study stabilized, while in the second group the hemoconcentration was increasing even during the rehydration and the levels of serum potassium and magnesium showed different tendencies. As follows from the results, in the calves suffering from scours accompanied by hemoconcentration the correction of the parameters of metabolic profile is necessary. 相似文献