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51.
A longitudinal observational study of 15 red deer farms was carried out in New Zealand for two years from March 1992. The deer were monitored for performance and health problems, and farm management practices were recorded. Numbers at risk were 4,683 hind-years, 2,459 stag-years and 3,202 weaner-years. The numbers of primiparous and adult hinds at risk of losing their progeny by weaning were 653 and 3,364, respectively. Where possible, postmortem examinations were carried out, and organs were sampled for histological and microbiological investigation. Rates of mortality varied with season with most stag and hind deaths in winter and weaner deaths in autumn and winter. Overall mortality rates were 1.77, 2.60 and 5.87 per 100 deer-years for hinds, stags and weaners, respectively. Malignant catarrhal fever accounted for 0.53 stag and 0.17 hind deaths per 100 deer-years at risk Misadventure, including broken bones, accounted for 15.4 per cent of weaner mortalities, or 0.53 weaner mortalities per 100 weaner-three months in autumn. Yersiniosis was confirmed in 18.6 per cent of weaner deaths, or 1.09 weaners per 100 weaner-years during the first six months after weaning, but was also suspected but unconfirmed in a further 41 per cent of weaner mortalities. Overall, 17 per cent of yearling hinds, and 9.2 per cent of adult hinds lost their progeny between pregnancy diagnosis in June and weaning in March. One outbreak of osteochondrosis was recorded. Mortality rates varied between farms and many mortalities were preventable. 相似文献
52.
J. K. Mack L. G. Alexander P. J. Morris B. Dobenecker E. Kienzle 《Journal of animal physiology and animal nutrition》2015,99(5):801-809
A meta‐analysis was conducted to understand quantitative aspects of calcium (Ca) and phosphorus (P) absorption in adult dogs and cats. 34 studies in dogs and 14 studies in cats met the criteria for inclusion in the meta‐analysis. Intake and faecal excretion values of Ca and P were subjected to a modified Lucas test and subsequent regression analyses. According to the current scientific consensus, Ca true digestibility (absorption) should increase at low Ca intake and decrease at high Ca intake. If true, this should result in a nonlinear relationship between the percentage of Ca excreted and dietary Ca intake. The present meta‐analysis showed a highly significant linear relationship (p < 0.0001) between Ca intake and Ca excretion suggesting a lack of systematic quantitative adaptation in true Ca digestibility. This finding suggests either that the time period covered by standard digestion trials is too short to induce adaptation mechanisms or that dogs and cats at maintenance will not efficiently alter quantitative Ca absorption percentage according to the amount ingested. If the latter is true, a dietary Ca supply differing greatly from the recommended dietary intake might impair the health of cats and dogs when fed long term. The data plots for P intake and faecal excretion were less uniform suggesting other factors not just dietary intake influence faecal P excretion. In adult cats, the dietary Ca:P ratio strongly influenced the true digestibility of P, whereas this effect was less marked in adult dogs. Faecal P excretion was significantly correlated to faecal Ca excretion in both species (p < 0.0001), and surprisingly, the level of P intake did not appear to be an important determinant of true digestibility of P. 相似文献
53.
54.
The spatial, temporal, and spatio-temporal features of the 2001 British foot-and-mouth disease epidemic in selected areas within the counties of Cumbria and Devon, which experienced the greatest incidence of disease, are described using hazard functions, extraction mapping and the space-time K-function. In Cumbria, the hazard of foot-and-mouth disease infection peaked at 2.8% in the week commencing 8 March 2001 and farm holdings in this area continued to be identified with disease to 12 September 2001. In contrast, peak infection hazard in Devon was 0.7% in the week commencing 15 March 2001 and eradication of the disease was achieved in this area by 31 May 2001. Persistence of the disease in Cumbria was consistent with: (1) many cattle holdings infected early in the epidemic (creating a high environmental viral load), and (2) a relatively large amount of medium-to-long-distance spread of the virus associated with seasonal farming activities-compounded to some extent by the movement of people and vehicles between disaggregated farm land parcels. The interaction of disease risk in Cumbria showed that premises remained infectious for longer throughout May, June and July, consistent with delays in disease detection during this period. 相似文献
55.
56.
Whistler JL Enquist J Marley A Fong J Gladher F Tsuruda P Murray SR Von Zastrow M 《Science (New York, N.Y.)》2002,297(5581):615-620
Recycling of the mu opioid receptor to the plasma membrane after endocytosis promotes rapid resensitization of signal transduction, whereas targeting of the delta opioid receptor (DOR) to lysosomes causes proteolytic down-regulation. We identified a protein that binds preferentially to the cytoplasmic tail of the DOR as a candidate heterotrimeric GTP-binding protein (G protein)-coupled receptor-associated sorting protein (GASP). Disruption of the DOR-GASP interaction through receptor mutation or overexpression of a dominant negative fragment of GASP inhibited receptor trafficking to lysosomes and promoted recycling. The GASP family of proteins may modulate lysosomal sorting and functional down-regulation of a variety of G protein-coupled receptors. 相似文献
57.
Birnbaum MJ 《Science (New York, N.Y.)》2008,319(5868):1348-1349
58.
Ammonia intoxication in the near-adult cat as a result of a dietary deficiency of arginine 总被引:2,自引:0,他引:2
Near-adult cats, fasted overnight, and given a single meal of a complete amino acid diet without arginine, developed hyperammonemia and showed clinical symptoms of ammonia toxicity within 2 hours. One cat (2.7 kilograms) died 4.5 hours after ingesting only 8 grams of the diet. Since ornithine also prevented hyperammonemia, it appears that the domestic cat cannot synthesize ornithine. 相似文献
59.
Gianmarco?Mugnai Federico?RossiEmail authorView authors OrcID profile Vincent?John?Martin?Noah?Linus?Felde Claudia?Colesie Burkhard?Büdel Stephan?Peth Aaron?Kaplan Roberto?De?Philippis 《Biology and Fertility of Soils》2018,54(1):27-40
Soil inoculation with cyanobacteria (cyanobacterization) is a biotechnological method widely studied to improve soil quality and productivity. During their growth on soil, cyanobacteria excrete exopolysaccharides (EPSs) which glue trichomes to soil particles, in a three-dimensional extracellular polymeric matrix. EPS productivity is an important screening parameter to select proficient inoculants and is affected by growth conditions and abiotic stresses. In this study, we evaluated the capability of the cyanobacterium Schizothrix cf. delicatissima AMPL0116 to form biocrusts when inoculated in sand microcosms under stressing conditions, and the characteristics of the synthesized polymeric matrix. In parallel, we evaluated the characteristics of exopolysaccharidic exudates of the strain when grown in liquid culture, under optimal growth setting. Our results pointed out at significant differences of the exopolymers produced in the two conditions in terms of monosaccharidic composition and molecular weight distribution, and proved the capability of S. cf. delicatissima AMPL0116 to form stable bioaggregates on sandy soils. 相似文献
60.
Alexander J. German Shelley L. Holden Thomas Bissot Penelope J. Morris Vincent Biourge 《Veterinary journal (London, England : 1997)》2010,183(3):294-297
A newly-formulated, high protein high fibre (HPHF) diet has recently been shown to improve satiety in dogs. The current study examined its performance during weight loss in client-owned dogs with naturally-occurring obesity. Fifteen dogs were fed the HPHF diet, whilst a matched ‘control’ group of 27 dogs, received a high protein medium fibre diet (HPMF), with an equivalent caloric density. Baseline characteristics (signalment, percentage overweight, and body fat percentage) were not significantly different between groups. However, percentage weight loss was greater (median [range] 31.8% [12.0–41.2%] vs. 20.0% [5.9–45.0%], P = 0.016) and mean rate of weight loss faster (median [range] 1.0%/week [0.3–1.6%] vs. 0.7%/week [0.3–1.5%], P = 0.028) on HPHF compared with HPMF. Percentage body fat mass decrease (measured by dual-energy X-ray absorptiometry) was also greater in dogs fed the HPHF diet (median (range] 58% [32–85%) vs. 37% [15–72%), P = 0.002). Thus, a diet formulated to include high levels of both protein and fibre, improves outcome during weight loss in obese dogs. 相似文献