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1.
Twenty-seven crossbred calves (1/2 Simmental, 1/4 Hereford, 1/4 Brahman) averaging 257 +/- 11 d of age were either hot-iron-branded (H), freeze-branded (F), or sham-branded (S). Calves were blocked for temperament, weight, and sex and were randomly assigned to day and order in which treatments were applied. To reduce stress from handling at treatment time, each calf was herded through the squeeze chute daily for 5 d before the experiment. Jugular cannulas were inserted in each calf 1 d before application of treatment. Blood samples and heart rate measures were obtained at -5, -3, 0, .5, 1, 3, 5, 10, 15, and 20 min after application of the treatments. Mean concentrations of plasma epinephrine (EPI) were higher for H calves at time .5 min than for either S or F calves (P = .10). To account for individual differences, prebranding heart rates and hormone concentrations were subtracted from subsequent samples and were also used to calculate a proportion for each subsequent sample. Analyses of subtracted values found that EPI concentrations were greater for H calves than for either S or F calves (P = .007) at .5 min postbranding. No other differences were found for the subtracted analyses. Analyses of proportion data also revealed that H calves had greater EPI than did either S or F calves (P = .027) at .5 min postbranding. Only three animals vocalized during branding, one H calf and two F calves. Despite the 5-d acclimation period, handling and restraint elevated plasma cortisol concentrations and heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Colleges and universities have an obligation to teach the basis of animal husbandry and welfare and must prepare students so that they can respond effectively to challenges by proponents of the animal welfare and animal rights movements. Veterinary curricula must now contain formal instruction in professional ethics and humane stewardship of animals for accreditation by the American Veterinary Medical Association. It is helpful if students have an understanding of farm animal behavior, stress physiology and methods of assessing welfare prior to learning about the animal welfare/rights movement's philosophies and issues. A review of early judicial practices, "classical" Judeo-Christian philosophy, the philosophy of Rene Descartes, Jeremy Bentham, Albert Schweitzer, and current philosophers and the entertainment media places the movements in perspective. Students should be familiar with such concepts as the mind-body controversy, equality of suffering, self-awareness or intelligence, and speciesism. After acquiring an appreciation of the basics, a knowledge of the issues facing animal agriculture and the arguments for and against each issue are necessary. Graduates of colleges of agriculture need to realize the potential effects the movements can have and take the initiative to improve the image of animal agriculture.  相似文献   
3.
Newcastle disease virus (NDV) has antineoplastic and immunostimulatory properties, and it is currently being clinically tested in anticancer therapy. In order to analyse the immunostimulatory effects of NDV on bovine papillomatosis, we inoculated 14 cows subcutaneously with an attenuated vaccine containing the LaSota strain of NDV (LS-NDV). Four cows with papillomatosis served as controls. Serum samples were collected from each animal 1 h preinoculation and 7 and 21 days postinoculation. In inoculated cows on days 7 and 21, the mean antibody titres were log2 2.43 ± 0.92 and 5.57 ± 0.72, respectively, by haemagglutination inhibition, and the mean levels of TNFα were 5.80 ± 4.19 and 5.39 ± 2.66 ng/mL, respectively, by WEHI-164 cytotoxicity assay. Significant differences between inoculated and control animals were evident for antibody titres on day 21 and clinical scores on day 60. A correlation was evident between the TNFα activities and clinical scores on day 21. The clinical observations at day 60 showed that the papillomas in five cows had completely resolved (36%), one animal had no alterations on clinical appearance of the tumour (7%), and papillomas in eight cows had regressed (57%). In conclusion, these results demonstrated that inoculation of LS-NDV vaccine stimulates an antibody response and a limited increase in TNFα activity and may enhance clinical recovery in bovine papillomatosis.
Funding: Scientific Research Council of Akdeniz University.  相似文献   
4.
The effect of glyphosate on leaves and basal bulbs of yellow nutsedge (Cyperus esculentus L.) plants was studied. Treatment with glyphosate did not affect leaf anatomy, although light necrotic spots were seen on the veins. In contrast, basal bulb organization was greatly affected with large necrotic zones and disorganization in the vascular cylinder due to herbicide accumulation. Depletion or disappearance of vacuolar phenols was observed in bulbs of plants treated with the highest doses of glyphosate. The most remarkable effect of glyphosate was the appearance of one layer of sclerenchymatic cells between root and rhizome primordia and the cortical tissues which could play an important role in the inhibition of rhizome and root emergence by the herbicide.  相似文献   
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6.
Cryptosporidiosis is an enteric disease of animals and humans that can be fatal in immunocompromised individuals. There is no known effective treatment for cryptosporidiosis. Bilbies are threatened marsupials and are bred in captivity as part of a recovery program to re-introduce this species to the southwest of Western Australia. Cryptosporidium muris infection was detected in the faeces of bilbies at a captive breeding colony. Stress associated with a high density of bilbies in enclosures may have predisposed some of the bilbies to infection with C. muris. C. muris has been described in mice and was found in the faeces of one mouse trapped in the breeding enclosures. It is likely the bilbies acquired the infection from mice by faecal contamination of food and water. The infection cleared within 2 months from some bilbies, however others remained infected for 6 months and treatment was attempted with dimetridazole. Subsequently the parasite was no longer be detectable in the faeces.  相似文献   
7.
Two cases of fatal cryptococcosis are described, one of Cryptococcus neoformans infection in a Gilbert's potoroo (Potorous gilbertii) and one of Cryptococcus gattii infection in a long-nosed potoroo (Potorous tridactylus). The diagnoses were confirmed by culture and specific immunohistochemistry, respectively. The long-nosed potoroo tested positive using the latex cryptococcal antigen test (LCAT), whereas the Gilbert's potoroo had a negative LCAT result despite having advanced disease of some duration. In both cases, the clinical presentation was a progressive neurologic disease associated with a central nervous system infection. Pulmonary infection was also observed in the long-nosed potoroo. Specific treatment with antifungal agents was unsuccessful in the long-nosed potoroo.  相似文献   
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9.
Nowak J  Friend AL 《Tree physiology》2005,25(2):245-250
Aluminum (Al) distribution among several cellular fractions was investigated in root tips of seedlings of one Al-resistant and one Al-sensitive family of slash pine (Pinus elliottii Engelm.) and loblolly pine (Pinus taeda L.) grown in nutrient solution containing 100 microM AlCl3 (pH 4) for 167 h. Aluminum present in 5-mm-long root tips was fractionated into cell-wall-labile (desorbed in 0.5 mM citric acid), cell-wall-bound (retained after filtering disrupted cells through 20-microm mesh) and symplasmic (filtrate following cell disruption) fractions. When averaged across both species, 12% of Al absorbed by root tips appeared in the symplasmic fraction and 88% in the apoplasmic fraction (55% as cell-wall-labile, and 33% as cell-wall-bound). On a fresh mass basis, total Al in root tips was lower in loblolly pine than in slash pine, lower in the Al-resistant slash pine family than in the Al-sensitive slash pine family, and lower in the Al-resistant families than in the Al-sensitive families across species. Although the data support the hypothesis that Al-resistant plants limit Al uptake to root apices, they do not exclude other mechanisms of Al resistance. Differential Al resistance between the species and between slash pine families may also be associated with the size of the total non-labile and cell-wall-labile Al fractions, respectively. We were unable to identify the basis for differential Al resistance in loblolly pine.  相似文献   
10.
Sitka spruce (Picea sitchensis (Bong.) Carr.) seedlings were supplied with solutions containing nitrogen (N) at 0.1 x or 2 x the optimum rate (low-N and high-N supply, respectively) and grown either outside in a control plot or inside open-top chambers and exposed to ambient (355 &mgr;mol mol(-1)) or elevated (700 &mgr;mol mol(-1)) CO(2) concentration ([CO(2)]). Gas exchange measurements, chlorophyll determinations and nutrient analysis were made on current-year (< 1-year-old) shoots of the upper whorl after the seedlings had been growing in the [CO(2)] treatments for 17 months and the nutrient treatments for 6 months. Total seedling biomass and biomass allocation were assessed at the end of the experiment. Nutrient treatment had a significant effect on the light response curves, irrespective of [CO(2)] or chamber treatment; seedlings supplied with high-N rates had higher net photosynthetic rates than seedlings supplied with low-N rates. The degree of photosynthetic stimulation in response to elevated [CO(2)] was larger in seedlings receiving high-N rates than in seedlings receiving low-N rates. Light-saturated net photosynthesis of seedlings grown and measured in elevated [CO(2)] was 26% higher than that of seedlings grown and measured in ambient [CO(2)]. There was no significant effect of [CO(2)] or chamber treatment on the CO(2) response curves of seedlings receiving High-N supply rates. In contrast, analysis of the CO(2) response curves of seedlings receiving Low-N supply rates showed acclimation to elevated [CO(2)]. Both maximum rate of carboxylation (V(cmax)) and maximum electron transport capacity (J(max)) were lower and J(max)/V(cmax) higher in seedlings in the elevated [CO(2)] treatment. There was no effect of elevated [CO(2)] on stomatal conductance, although it was highly dependent on foliar [N], ranging from ~60 mmol m(-2) s(-1) at ~1.5 g N m(-2) to 200 mmol m(-2) s(-1) at ~5 g N m(-2). In the high-N and low-N treatments, foliar N concentration was 10 and 28% lower in seedlings grown in elevated [CO(2)] than in seedlings grown in ambient [CO(2)], respectively. There was no [CO(2)] effect on foliar phosphorus concentration ([P]). Chlorophyll concentration increased with increasing N supply in all treatments. There was no significant effect of elevated [CO(2)] on specific leaf area. Chlorophyll concentration expressed either on an area or dry mass basis for a given foliar [N] was higher in seedlings grown in elevated [CO(2)] than in seedings grown in ambient [CO(2)]. Elevated [CO(2)] increased total biomass accumulation by 37% in seedlings in the high-N treatment but had no effect in seedlings in the low-N treatment. There was a proportionally bigger allocation of biomass to roots of seedlings in the elevated [CO(2)] + low-N supply rate treatment compared with seedlings in other treatments. This resulted in a reduction in aboveground biomass compared with corresponding seedlings grown in ambient [CO(2)].  相似文献   
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