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991.
H.S. Cameron D.V.M. Ph.D. 《New Zealand veterinary journal》2013,61(3):41-44
Extract First let me express my appreciation of being the recipient of a Fulbright Fellowship for research in New Zealand and also for the privilege of discussing brucellosis before the New Zealand Veterinary Association. 相似文献
992.
C.H.G. Irvine B.V.Sc. N.G. Prentice M.B. Ch.B. M.R.A.C.P. 《New Zealand veterinary journal》2013,61(4):86-88
Extract In conjunction with a trial to determine the effect of nematode infestation upon the liveweight gain and wool production of young sheep (Brunsdon, unpublished), information was sought on the seasonal succession and availability on pasture of infective larvae of the principal trichostrongyle genera parasitic in sheep. Data were collected in the form of nematode populations found at postmortem examination of Romney lambs, previously maintained worm-free, which were exposed to risk of parasitism in the field. A series of these lambs ran with the flock in the above-mentioned trial and served as indicators of the abundance of infective larvae on the pasture. 相似文献
993.
B.A.H. Jones 《New Zealand veterinary journal》2013,61(3)
Extract Madam:– Infectious bursal disease (IBD) is recognised as a serious economically significant disease of poultry. N.H. Christensen in his letter to your Journal (1) has summarised the ways in which IBD causes such economic loss. 相似文献
994.
B. M. Buddle M. Herceg M. J. Ralston H. D. Pulford K. R. Millar D. C. Elliott 《New Zealand veterinary journal》2013,61(4):167-170
A study was undertaken to indicate the importance of different causes of death in goats and to investigate the management factors which influence these problems. Over a 15 month period, 324 dead goats were received from 67 farms in the Horowhenua, Wairarapa, Wanganui and Wellington regions. Although a wide range of diseases was encountered in the study, the major causes of mortality could be divided into 4 groups: problems directly related to management, microbial diseases, nematode parasitism, and trace element related deficiencies and toxicities. The highest proportion of deaths related directly to management problems and included deaths from hypothermia, mismothering, premature birth, ruminal acidosis, pregnancy toxaemia, trauma, and plant and chemical toxicities. In larger flocks, microbial diseases including Pasteurella pneumonia and yersiniosis were major problems. Deaths from nematode parasitism were predominantly observed in goats 12 months of age and older. White muscle disease (selenium/vitamin E deficiency) was the major trace element deficiency causing death in goats. The influence of factors including age of goat, flock size and management practices on the major causes of death are discussed. 相似文献
995.
C. H. Donaldson D. M. Kelk K. N. West 《African Journal of Range and Forage Science》2013,30(1):112-116
Grondwaterherverspreiding vind vinnig in die hele grondprofiel van drie subhabitatte nl. Eragrostis pallens, Ochna pulchra en Grewia flavescens van ‘n Burkea‐savanna plaas. Na ‘n reënbui van 50 mm herversprei water binne 12 uur tot op ‘n diepte van 90 cm in ‘n sandgrond wat as die Chesterserie van die Huttonvorm geklassifiseer is. In die E. pallens en O. pulchra subhabitatte vind wateropname hoofsaaklik in die boonste 60 cm van die grondprofiel plaas terwyl vog vrylik beskikbaar is in die ondergrond selfs in die droogste maande nl. Junie, Julie en selfs Augustus. In die G. flavescens subhabitat vind wateropname deur die hele grondprofiel plaas tot op ‘n diepte van 120 cm. Die G. flavescens subhabitat blyk meer onderhewig aan vogstremminge te wees. 相似文献
996.
Summary In a flock of 40 ewe lambs of the Texel breed the anthelmintic oxfendazole was tested in two different formulations, a 2.265 per cent suspension and a 4 gram bolus containing 151 mg active ingredient. All treatments were based on a dose rate of 5 mg / kg body weight. Faecal examinations and larval differentiations were carried out on the day of treatment and two and seven days later. No differences in efficacy were apparent between the two treated groups. Oxfendazole in either formulation was 100 per cent effective in removing the major strongylids and trichostrongylids. A lower activity was seen against Strongyloides papillosus. 相似文献
997.
H. J. W. M. Cremers 《The Veterinary quarterly》2013,33(3):198-199
Summary The feet of three two‐humped camels (Camelus bactrianus), one lama (Lama glama) and four alpacas (Lama pacos) from zoos and a circus in the Netherlands were examined for the mange‐mite Choroptes bovis. Mites were found on two of the camels, the lama, and three of the alpacas. On one camel and one alpaca small mange lesions on the feet were present. This is the first report of Chorioptes bovis and chorioptic mange in the two‐humped camel. 相似文献
998.
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
999.
J. Kirpensteijn R.J. Maarschalkerweerd I. van der Gaag H.S. Kooistra F.J. van Sluijs 《The Veterinary quarterly》2013,33(2):67-70
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
1000.
R.H. Drewes 《African Journal of Range and Forage Science》2013,30(4):174-178
A host of grassland management systems have been published and recommended. Whereas earlier approaches to grassland management emphasized the systematic resting aspect, the systems published since 1966 have tended to stress the degree of utilization of the grassland sward. In an attempt to accommodate the periodic dry periods that are so typical of the semi‐arid grasslands of western Transvaal, the Potch system of management was evolved. It aims at the development of a fodder reserve, firstly by delaying the commencement of summer grazing, and secondly, by allowing prolonged periods of absence in the grazing rotation. High utilization grazing within the concept of controlled selective grazing is prescribed. This approach was tested and demonstrated over a period of five years in an experiment comprising 240 beef breeding cows. It appeared that generally, summer grazing only commenced after the third week of November, and that the mean period of occupation amounted to 20 days, with a period of absence of 87 days. A conception rate of 85% of all the cows and heifers mated, was achieved. A stocking rate of 0.53 LSU ha?1 could be maintained in an area where the general grazing capacity is 0.33 LSU ha?1. 相似文献