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991.
Ruminai acidosis was induced in twenty-one 10-month-old West African Dwarf Goats by feeding a suspension of 80 g wheat flour per kg body-weight (day 0) through a stomach tube. Ruminai and systemic acidosis was diagnosed on day 1 in all goats. Clinical signs included loss of rumination and appetite, trembling, and watery diarrhoea. The detection of acidic faeces during the first 24h was considered of diagnostic importance. Subgroups were treated orally on days 1,2, and 3 either with 1 g of sodium bicarbonate per kg bodyweight, with 1 g of baking yeast per kg, or with a combination of these treatments at 0.5 g of each per kg. A fourth group served as untreated controls.Peroral bicarbonate neutralization was highly effective in the treatment of rumen acidosis, whereas the use of yeast was found ineffective. The combined treatment had a moderate effect probably due to the bicarbonate.Three fatal cases (60%) occurred in the untreated group compared with none in the bicarbonate group, and 2 in each of the remaining groups. This corresponded to 33% of the yeast treated group and 40% of the combined treated group. Details were given on post mortem examinations performed on all survivors on day 11. Lesions included subacute rumenitis and abomasal ulcers. No lesions were found in 3 of the bicarbonate treated goats and in 2 of the animals receiving combined treatment.  相似文献   
992.
Four farms that group-housed sows from 2 weeks of lactation until weaning (G-farms) and 3 farms that kept the sows individually penned throughout the 5 to 6-week-long lactation period (C-farms), were compared in terms of sow health. All sows were crossbred Swedish Yorkshire × Swedish Landrace. The daily food ration was similar on all farms except during the group-housing period, when G-farm sows were fed ad libitum. Sows were grouped in the breeding section and kept grouped on deep litter in the dry sow section on all farms. Individual health examinations were performed at the time of weaning (±4 days) on 179 G-farm sows and on 167 C-farm sows. Teat- and udder skin wounds occurred less frequently (p<0.001) in G-farm sows than in C-farm sows. In addition, preweaning atrophy of all mammary glands occurred in 6.6% of the G-farm-sows but not in a single C-farm sow (p<0.001). This indicates that sow-piglet interactions decrease when sows are group housed. However, these differences did not occur in primiparous sows, suggesting that the relation between the primiparous sow and her litter is not affected. Mastitis frequency was the same in the 2 systems. Moreover, the frequency of locomotor disorders was the same in the 2 groups, and hoof overgrowth was common in both systems. These similarities could be due to the fact that all farms group housed dry sows on deep litter. A strong relation (p<0.001) between hoof overgrowth and locomotor disorders was evident. Low access to food due to low rank among primiparous group-housed sows was indicated by a lower (p<0.05) backfat thickness compared with multiparous sows, and a higher (p<0.001) frequency of skin wounds compared with individually housed primiparous sows.  相似文献   
993.
Weakness, lethargy, ataxia, lateral recumbency, limb paddling, tremors, salivation, and diarrhea were observed in newborn pigs on a commercial swine farm. Many pigs became moribund and died. All had been treated with an aerosol wound spray containing 2.5% chlorpyrifos. A controlled study was undertaken to determine whether the aerosol spray was the cause of these clinical signs. Pigs exposed to aerosol spray containing 2.5% chlorpyrifos at 3 hours (n = 4) and 6 hours (n = 3) after birth developed clinical signs similar to those on the farm; none survived. Pigs exposed at 24 hours (n = 5) after birth developed clinical signs consistent with those that had developed in pigs on the farm; 3 died and 2 survived. Of 3 pigs exposed to the same spray at 36 hours after birth, 1 developed tremors 7.5 hours later and diarrhea 9 hours later, then returned to normal.  相似文献   
994.
The effect of vehicular saline solution volume on early lesions induced in rats by intratracheal administration of silica was evaluated. Seventy-two male Long-Evans rats were randomly assigned 6 each to 12 factorial groups (3 X 2 X 2): 3 doses of silica (0, 2.5, and 5 mg), 2 volumes of vehicle (saline solution; 0.1 and 0.5 ml), and 2 postinoculation times (1 and 3 days). Lactate dehydrogenase and alkaline phosphatase activities in the bronchoalveolar lavage fluid supernatant and cell viability of bronchoalveolar cells were used as indicators of cell injury. The number of pulmonary alveolar macrophages and polymorphonuclear leukocytes were used as indicators of inflammatory response. Dose of silica and postinoculation time had a significant (P less than 0.05) effect on the biochemical and cellular composition of lavage fluid. The volume of vehicle in which silica was suspended significantly (P less than 0.05) enhanced the pulmonary injury and inflammatory response. However, dose-volume interaction was only significant (P less than 0.05) in 1 of 6 parameters, indicating that the effect was additive, but not synergistic, in nature. Seemingly, vehicle volume had an enhanced effect on the injury and the inflammatory response induced by intratracheal inoculation of silica.  相似文献   
995.
Two separate groups of nine-week-old specific pathogen free cockerels maintained in isolation were infected with a field strain of infectious laryngotracheitis (ILT) virus, either by intratracheal or combined intranasal and supraconjunctival inoculation. Birds were monitored for virus shedding from five sites on alternate days during the acute phase and three times weekly until week 17. They were then treated with cyclophosphamide on three consecutive days and thereafter swabbed daily. During the acute phase clinical signs were observed and virus was recovered from ocular and nasal sites for up to six to eight days. Initially after the acute phase no virus could be detected. However, from the seventh week after infection intermittent, apparently spontaneous shedding was detected in four of five birds in each group. There was no clear effect of cyclophosphamide treatment on re-excretion patterns, possibly because of the high levels of virus shedding already occurring. Thus, a carrier state for ILT virus has been demonstrated experimentally in live clinically recovered birds.  相似文献   
996.
Propofol as an intravenous anaesthetic agent in dogs   总被引:1,自引:0,他引:1  
Studies in dogs with an emulsion formulation of the intravenous anaesthetic, propofol, showed that induction of anaesthesia was smooth and it was possible to maintain anaesthesia by intermittent injection. The mean dose for induction of anaesthesia in unpremedicated dogs was 5.95 mg/kg body-weight. When no premedication was administered anaesthesia was maintained by a total dose of approximately 0.806 mg/kg/minute. Premedication with between 0.02 and 0.04 mg/kg of acepromazine reduced the mean induction dose by about 30 per cent and the maintenance dose by more than 50 per cent. In 68 unpremedicated dogs given one dose, recovery was complete in a mean time of 18 minutes and after maintenance of anaesthesia by intermittent injection in 65 dogs the mean recovery time was 22 minutes from administration of the last dose. Premedication with acepromazine did not produce statistically significant increases in these recovery times. The quiet, rapid and complete recovery proved to be most valuable in cases where the animal had to be returned to the owners' care with the minimum of delay.  相似文献   
997.
998.
999.
1. The effect of 100 g rapeseed meal (RSM)/kg diet on the energy metabolism of hybrid laying hens was examined by indirect calorimetry. Thyroid hormone concentrations, thyroid weight, liver weight and body weight, egg production and food intake were also measured. 2. Fasting heat production was significantly lower in hens receiving RSM than in controls, but this difference disappeared when the birds were fed. 3. Thyroid hormone concentrations decreased, while thyroid and liver weights increased slightly; none of these effects was significant. Body weight, egg production and food intake were unaffected and no liver haemorrhages were noted. 4. The maintenance metabolisable energy (ME) requirement of control and treated birds, estimated from short-term energy balance measurements, was 474 kJ/kg0.75 d; net availability of ME in both treatments was 0.85.  相似文献   
1000.
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