摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34827

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Leptospiruria in possums (Trichosurus vulpeculu) experimentally infected withbalcanicawas monitored for 13 months by dark-field microscopy, inoculation of hamsters and culture. Leptospiraemia was monitored by inoculation of hamsters and culture for the first 28 days post-inoculation.

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34828

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Various physical characteristics of horses affected with laryngeal hemiplegia were studied. Appropriate comparisons were made with the populations from which the affected animals were obtained. Statistical evidence is presented which supports the widely held clinical impression that heavy, young, male animals are most susceptible to the disease.

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34829

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1981.36672

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Fifty-five dogs, 6 to 18 months old, from 11 areas of New Zealand were examined for gastro-intestinal helminths. Thirty-eight (69.1%) were infected. Twenty-one (38.2%) hadToxocara canis, 20 (36.4%)Trichuris vulpis, 20 (36.4%)Uncinaria stenocephala, 3 (5.5%)Toxuscaris leonina, 3 (5.5%)Dipylidium caninumand 1 (1.8%)Taeniasp. Helminth infections were less frequent and populations were smaller in females than in males.

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34830

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

A breakeven analysis suggests that the economy of inducing cows to calve prematurely is precariously balanced. The analysis is based on data from recent New Zealand publications and on replies to a questionnaire sent to participants in a previously reported induction trial. It suggests that the extra cost per induction is $18.60, that the cost saved is $23.40 and that the income lost $28.80. This implies that extra returns have to be about $24.00 to achieve a nil balance and it is suggested that this might be just possible during the first lactation after induction. Any profit will have to come from advantages beyond the first year. The questionnaire data indicate that about 2/3 of induced cows are likely to provide such advantages, but that 1/3 might cause further losses. It is recommended that the technique of inducing dairy cows to calve prematurely be judiciously employed, mainly in emergency, on young and healthy cows only.

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34831

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Of the 3 species of salmon successfully acclimatised in New Zealand, the quinnat,Oncorhynchus tshawytscha(Walbaum) is the most widespread. It is found mainly in the east coast rivers of the South Island. Although adults live in the sea and return to freshwater to breed, lake populations have developed either voluntarily or because egress to the sea is blocked by dams. Sea-living adult quinnat salmon return to rivers in summer to spawn in their natal streams and once in freshwater, cease feeding and the gut degenerates. Eggs laid by the females in redds are fertilised by the male, after which both parents die. Most young salmon emerging from the redds migrate downstream but their fate is uncertain. The few remaining feed and grow and migrate to sea in early summer. Examination of the ridges on fish scales reveals information about migration patterns which assists in studies conducted by the Ministry of Agriculture and Fisheries in the Glenariffe Stream. Marking and tagging of smelts is expected to provide information on survival to adult return and on movements of salmon at sea. The quinnat is the salmon species most favoured by anglers and it is also considered to have a commercial future in New Zealand, using the method of ocean ranching.

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34832

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1981.34833

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor