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61.
Reference values for haematological and blood biochemical variables may vary per breed and are influenced by age and, to a certain extent, by rearing conditions. To investigate the influence of age and rearing conditions, these variables were measured in Dutch Warmblood foals from birth to 5 months of age. The foals were divided into three groups with different exercise regimens: 14 foals got boxrest with no exercise; 14 foals were kept in comparable boxes, but received daily exercise; and 15 foals were maintained on pasture with free exercise. Blood samples were collected each month and 36 haematological and biochemical variables were measured. The influence of age and rearing conditions was statistically evaluated. Significant age effects were found for all variables with the exception of band-shaped leucocytes, eosinophilic leucocytes, basophilic leucocytes, monocytes, platelets, pCO2, and sodium, potassium, calcium, magnesium, creatinine and creatine phosphokinase levels. Rearing conditions appeared to influence the haemoglobin, packed cell volume, pH, base excess, bicarbonate, chloride, urea, and alkaline phosphatase values. Most age-related differences can be explained by growth and differentiation-related processes that are specific for young animals. Differences due to the different rearing conditions can partly be explained by the higher metabolism and greater maturation of tissues in foals maintained on pasture with free exercise. Some other differences were minor and were probably of no clinical relevance. The conclusion is that haematological and blood biochemical variables in the Dutch Warmblood foal mainly depend on age, thus warranting the use of specific age-related reference values for foals of this breed.  相似文献   
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Summary

Twenty four maiden heifers were bred by natural route by a specific immunotolerant bull, that was persistently infected with Bovine Viral Diarrhoea virus (BVD virus). The quality of the bull's semen was normal. Twelve heifers became pregnant in the first oestrus cycle and the remaining twelve in the second oestrus cycle. This leads to the conclusion that such persistently infected bulls may have good fertilisation results. Nevertheless, it is felt that bulls persistently infected with the BVD virus must be excluded from artificial insemination centres because of the risk of introducing BVD virus in a herd by the semen.  相似文献   
64.
Summary

The macroscopic and histological appearance of jejunal antimesenteric incisions approximated with two different absorbable suture materials (monofilament versus multifilament) and three closure techniques (appositional single layer, crushing single layer, and double layer) were compared in healthy dogs at 14 or 28 days, postoperatively. No significant differences between the two suture materials were observed for most of the macroscopic or histological variables. However, the monofilament suture material caused significantly more fibrous tissue reaction in the muscular layer of the jejunum than did the multifilament suture material. Of the three enterotomy closure techniques used in this study, the appositional single‐layer method proved to be the best. The double‐layer closure method caused a significant decrease in the incisional circumference, the relative circumference, and volume of the jejunum, and a significant increase in jejunal wall thickness. Our findings suggest that canine jejunal enterotomy incisions can be closed using an appositional suture pattern with relatively rapidly absorbable monofilament suture material. The use of double‐layer suture patterns for closure of jejunal enterotomy incisions should be avoided because the size of the intestinal lumen may be reduced.  相似文献   
65.
Nycticeius schlieffenii is a monestrous species that breeds during the spring months in the northern parts of the Kruger National Park. During spring 1983 the average number of corpora lutea in 11 Nycticeius schlieffenii females was 3,1 (range 1 -4), with the average number of fetuses recorded 2,8. In the present study this bat has been found to be a polyovular seasonal breeder, giving birth to as many as three young per estrous cycle.  相似文献   
66.
Breeding success of Pterodroma macroptera, Procellaria aequinoctialis and Pachyptila vittata salvini in three cat-free and three control areas were used to evaluate the effects of cat Felis catus predation on the avifauna of Marion Island. Breeding success of all three species was significantly higher in the combined cat-free areas than in the combined control areas. However, breeding success in one cat-free area failed to show a significant difference from its particular control area, probably as a result of higher skua (Catharacta antarctica) predation inside the cat-free area. Chicks of P. macroptera and P. aequinoctialis were especially vulnerable to cat predation, since cats can enter their nesting burrows. P. macroptera was seriously affected by cat predation because it is the most abundant of only two winter-breeding petrels. Significant changes in the number of nest visits by these petrels during their breeding season followed hatching dates, which in turn were concomitant with, or were followed by significant differences in the combined breeding success between the cat-free and control areas. The cat-free areas show that an elimination of cat predation would still favour the recovery of the petrel population.  相似文献   
67.
Newcastle disease virus (NDV) causes significant economic losses to the poultry industry in Southeast Asia. In the present study, 12 field isolates of NDV were recovered from dead village chickens in Vietnam between 2007 and 2012, and were characterized. All the field isolates were classified as velogenic. Based on the sequence analysis of the F variable region, two distinct genetic groups (Vietnam genetic groups G1 and G2) were recognized. Phylogenetic analysis revealed that all the 12 field isolates fell into the class II genotype VII cluster. Ten of the field isolates, classified as Vietnam genetic group G1, were closely related to VIIh viruses that had been isolated from Indonesia, Malaysia, and Cambodia since the mid-2000s, while the other two field isolates, of Vietnam genetic group G2, clustered with VIId viruses, which were predominantly circulating in China and Far East Asia. Our results indicate that genotype VII viruses, especially VIIh viruses, are predominantly responsible for the recent epizootic of the disease in Vietnam.  相似文献   
68.
An Internet-based questionnaire among horse owners was carried out to identify factors affecting the incidence of insect bite hypersensitivity (IBHI) among horses in the Netherlands. Information was obtained for 794 horses of various breeds, but the breed distribution was not representative for the Dutch horse population. Of the horses for which information was available, 56% suffered from IBH and 44% did not. The most common clinical symptoms were pruritus, scaling, and hair loss, occurring mainly at the base of the tail and along the mane. Breed, age, region (and local habitat), stabling, type of bedding in the stable, use of the horse, deworming frequency, and season were associated with significant differences in IBH incidence. Knowledge of the factors influencing the incidence of IBH may make it possible to reduce the number of animals affected and help alleviate symptoms in affected horses.  相似文献   
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