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991.
The demographic characteristics of the veterinary profession in New Zealand are examined using information supplied by registered veterinarians to the Veterinary Surgeons Board in their applications for annual practising certificates in 1985. Comparisons are made with the veterinary professions in other similar countries, and with the medical and paramedical professions in New Zealand. In 1985 1308 registered veterinarians were working in New Zealand and 304 were overseas, whereas in 1976 the equivalent figures were 748 and 182. This represents an increase of 73% in the number of registered veterinarians in the last 10 years. Eighteen percent of veterinarians were female. The mean age of veterinarians was 38 years, but females in the profession were on average much younger (32 years) than males (42 years). Clinical practice provides employment for 70% of veterinarians: of these 59% work principally with farm animals and 41% with non-farm animals. The remaining veterinarians are employed by Government (22%), University (5%) and Industry (3%). The current demographic structure of the profession has been markedly influenced by the opening of New Zealand's only veterinary school at Massey University in 1963. Differences from other medical professional populations in New Zealand and overseas principally reflect the marked change in the number and sex ratio of graduates entering the veterinary profession since that time. It will take about another twenty years before the population reaches a stable age and sex structure, assuming that current graduation patterns persist throughout that period. Because the structure of the population is changing, considerable caution is needed in predicting future employment trends from data for a single year.  相似文献   
992.
Fifteen mature cows and 12 two-year-old heifers were superovulated with purified follicle stimulating hormone (FSH-P) to study the relationship between FSH-P dose level and response (measured as number of palpated corpora lutea (CL) and plasma progesterone concentration). The cattle came from a high prolificacy breeding herd for which cows were originally purchased after producing at least two sets of twins; the heifers were bred in the herd. At dose levels of 8, 16, 24 and 28 mg FSH-P in cows, averages respectively of 2.3, 3.5, 6.9 and 11.1 palpable CLs were found. There was an average difference in response of two CLs between heifers and cows (higher in heifers, though not significantly so). The relationship found between progesterone concentration and CL number could be a useful indicator of superovulation success in future experiments. The regression for cows was 1.25±0.11 ng/ml progesterone per unit increase in CL number, with a correlation of 0.92 between the two variables over the CL range 1 to 25. The corresponding value for heifers was 2.74±0.24 ng/ml per CL (correlation 0.94), or 2.50±0.40 ng/ml per CL (correlation 0.83) if one record (29 CL, 84 ng progesterone/ml) was excluded.  相似文献   
993.
CASE HISTORY: Twelve of 150 goat kids, 4–10 days old, died 3 days after disbudding with a hot iron. Another 18 kids had been ill the previous day but survived following antibiotic therapy. Five of the dead kids were necropsied.

PATHOLOGICAL FINDINGS: There was necrosis and haemorrhage of the skin, subcutaneous tissues and frontal bone at disbudding sites in all five kids examined post mortem. Beneath disbudding sites in 4/5 kids there were bilateral, dark red, often cavitated areas of necrosis extending deep into the frontal cortex of the brain. Histologically, these areas consisted of coagulation necrosis, haemorrhage, vascular thrombosis and suppurative inflammation. Numerous bacteria, predominantly large Grampositive rods, were present in the necrotic brain tissue. In the remaining kid, bilateral areas of yellow discolouration and flattening of gyri in frontal lobes corresponded histologically to extensive polioencephalomalacia. A mixed growth of aerobes and anaerobes was cultured from the brain of one kid with suppurative lesions.

CLINICAL RELEVANCE: Thermal disbudding of neonatal kids is widely practised in dairy goat herds and is considered the method of choice for disbudding in New Zealand. However, the skull of goat kids is much thinner than that of calves and the safety margin for thermal injury to the brain is markedly reduced. This report highlights the risks associated with the technique and its potential as a welfare issue.  相似文献   
994.
995.
Necropsies of 228 ferrets captured from eight areas in the North and South Islands provided material for an investigation into the epidemiology of tuberculosis in feral ferrets. Mycobacterial culture of pooled lymph nodes (retropharyngeal, respiratory and jejunal) identified the prevalence of infection to be much higher than that estimated from gross lesions only. Seventy-three of the 228 animals examined (32%) were diagnosed as tuberculous. Fifty-three culture-positive ferrets and 18 seemingly uninfected animals were subjected to detailed histopathological examination. The outcomes of these investigations, including the characteristics of the disease, distribution of lesions and aids to diagnosis, are presented.

Of the feral carnivores found in New Zealand, the disease persists at high prevalence only in ferrets, and is probably maintained principally by ingestion of tuberculous carrion. The course of the disease may be prolonged in some ferrets, but tuberculosis eventually causes the death of many infected animals. Microscopic hepatic granulomas may be considered pathognomonic of the disease, and have potential to be used as a rapid diagnostic tool in ferrets with no gross lesions.  相似文献   
996.
CASE HISTORY: Investigations were conducted to determine the cause of an acute, multi-farm outbreak of porcine respiratory disease that included diarrhoea and subsequent loss of body condition in affected pigs. A definition for post-weaning multisystemic wasting syndrome (PMWS) including both clinical and pathological features, previously developed for the pig industry in New Zealand, was applied to the current outbreak. In addition to self-reporting by owners of affected farms, local veterinarians, disease and epidemiology consultants, and animal health officials from the Ministry of Agriculture and Forestry (MAF) were involved in conducting farm visits and submission of diagnostic specimens.

CLINICAL FINDINGS AND DIAGNOSIS: Pathogens known to be endemic in the pig industry in New Zealand as well as likely exotic diseases were excluded as causative agents of the outbreak. Clinical signs including dyspnoea, diarrhoea, and rapid loss of body condition were consistent with the New Zealand case definition for PMWS. Interstitial pneumonia, pulmonary oedema, generalised lymph-node enlargement, and presence of porcine circovirus type 2 (PCV2) inclusion bodies were consistently identified in affected pigs. Classical swine fever virus (CSFv), Porcine reproductive and respiratory syndrome virus (PRRSv), and Influenza virus were ruled out, using molecular and traditional virological techniques. Spread of the disease between farms was hypothesised to be facilitated by locally migrating flocks of black-backed seagulls. The original source of the disease incursion was not identified.

DIAGNOSIS: Based on the consistent presence of circovirusassociated lesions in lymphoid tissues in combination with generalised enlargement of lymph nodes, histiocytic interstitial pneumonia, clinical wasting, and poor response to antibiotic therapy, a diagnosis of PMWS was made.

CLINICAL RELEVANCE: PMWS should be considered in the differential diagnoses of sudden onset of respiratory dyspnoea, diarrhoea, and rapid loss of body condition in young pigs in New Zealand pig herds.  相似文献   
997.
Three trials were completed to compare different regimes for the use of an analogue of prostaglandin F2 alpha(“Estrumate”: ICI) in the breeding management of herds of lactating dairy cows with seasonally concentrated calving patterns. The first regime involved two injections of ‘Estrumate’ 11 days apart, followed by insemination, either at 72h and 96h after the second injection, or at the first observed oestrus. Every cow had calved at least 40 days before the first injection. The second regime involved a single ‘Estrumate’ injection given to every cow not inseminated during the first seven days of the breeding programme. Treated cows were inseminated when observed in oestrus within 48h of injection, or at 72h and again at 96h. The third regime utilised the technique of tail-painting during the pre-mating period to identify groups of cycling cows which were subsequently givena single injection of “Estrumate” and inseminated 72h lateror at a subsequent behavioural oestrus.

All regimes significantly altered the conception pattern from that obtained in untreated herd-mates. The variable incidence of post-partum anoestrus, genuine short oestrous cycles and the degree of precision in oestrus synchronisation in lactating dairy cows resulted in many animals being unnecessarily injected and/or inseminated. The third regime overcame most of these problems and could have application in many largeherds. The identification of cycling animals and insemination at detected oestrus are important components of programmes using prostaglandins for the purpose of oestrus synchronisation in lactating cows in seasonal dairy herds.  相似文献   
998.
AIMS: To determine the effects of liveweight and condition score of ewes at mating, and shearing mid-pregnancy, on birthweights and growth rates of twin lambs from birth to the time of weaning, and; to determine whether any effect of condition score is independent of liveweight.

METHODS: Romney ewes (n=435) which conceived within a 17-day mating period and successfully gave birth to and reared twin lambs to weaning were used. Ewes were managed during pregnancy so that their total liveweight increased at a level equivalent to the expected growth of the conceptuses. Approximately half of the ewes were shorn 70 days after the mid-point of mating, and the remainder were left unshorn, at which time they had 6-months' wool growth. All lambs were weighed within 12 h of birth and again at weaning.

RESULTS: There was a significant linear relationship (R2=0.99) between mean group liveweight and condition score of ewes at mating (difference of 7.3 kg per 1.0 unit condition score). Liveweight of ewes at mating had small but significant (p<0.05) positive effects on both birthweights and growth rates of twin lambs to weaning. Ewes that had condition scores of 3.5–4.0 (scale 0–5) at mating gave birth to significantly (p<0.05) lighter lambs than ewes that had condition scores <3.5. The condition score of ewes at mating was positively associated with growth rates of lambs, although this effect was largely explained by variation in the liveweight of ewes at mating.

Twin lambs born to ewes shorn mid-pregnancy were significantly (p<0.05) heavier at birth (by 0.4 kg) and at weaning (p<0.05) than those born to unshorn ewes. The heavier weaning weights of lambs born to ewes shorn mid-pregnancy were due to a heavier birthweights rather than increased growth rate.

CONCLUSIONS: Liveweight and condition score of ewes at mating had small positive effects on growth rates to weaning of twin lambs. Shearing mid-pregnancy increased birthweights and weaning weights of twin lambs. To achieve high weaning weights of twin lambs, farmers should ensure ewes attain high liveweights and condition scores at mating and shear mid-pregnancy. It is speculated that the effects of liveweight and condition score of ewes at mating on weaning weights of twin lambs would be greater than those observed in the present study under conditions in which nutrition of the dam is below optimum.  相似文献   
999.
雷州半岛尾叶桉人工林耗水量研究   总被引:13,自引:0,他引:13       下载免费PDF全文
利用热脉冲技术对雷州半岛2种主要土壤类型下的4年生尾叶桉人工林林分耗水量进行了为期1 a的观测,并对林分耗水与林分生长特性、气象因子及4 m深土壤有效水关系进行研究.研究结果表明:尾叶桉人工林边材面积与胸径具有显著的相关性,利用边材面积进行单株向林分尺度耗水的转换可行;河头、纪家尾叶桉人工林日平均茎流密度分别为2 772、1 839 L·m-2·d-1;日平均耗水量分别为1.49、1.53 mm;河头与纪家尾叶桉人工林林分的年耗水量分别为542、559 mm,分别占年降水量的35%、36%;开阔的林冠及较小的叶面积指数、旱季时土壤有效水的减少及较低的饱和蒸汽压差等在不同程度上都限制了桉树的耗水量.  相似文献   
1000.
OBJECTIVE: Duck and chicken egg yolk were compared for their protective effects against cold shock during the cryopreservation of stallion sperm in a lactose-EDTA-glycerol cryodiluent. DESIGN: A completely randomised design was used. Procedure Ejaculates from five stallions (n = 14 ejaculates) were split and diluted to either 20 or 200 x 10(6) sperm/mL in a lactose-EDTA extender containing either duck or chicken egg yolk. The extended semen was then frozen in liquid nitrogen. The percentage of sperm total motility and forward progressive motility were assessed before freezing and at 0 and 1 hr after thawing. Morphology data were also collected at 0 and 1 hr post thaw. RESULTS: Total and forward progressive motility were higher when the sperm were frozen in the presence of duck rather than chicken egg yolk. Furthermore, the total and forward progressive motility and percentage of morphologically normal sperm were higher when frozen at a concentration of 200 than 20 x 10(6)/mL. CONCLUSION: The results of this study demonstrate that the motility parameters of stallion sperm are improved when the semen is frozen in lactose EDTA extender supplemented with duck egg yolk rather than chicken egg yolk. Moreover, sperm motility and the percentage of morphologically normal sperm were higher after freezing at a concentration of 200 x 10(6)/ml rather than 20 x 10(6)/ml.  相似文献   
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