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71.
The intensification of pastoral animal production results from several major developments including increased forage production and utilisation, diet supplementation, breeding animals to increase milk, meat or wool production, and changes in management. The impact of increased intensification on welfare will differ across species and systems. More intensive-grazing systems and the feeding of novel forages will underpin all moves to intensification. More intensive grazing generally reduces opportunities for shade and shelter. Improved nutrition will generally benefit welfare but competition for available feed may cause increased social pressure. Increased flock and herd size will be associated with a reduction in the human:animal ratio and less time to observe individual animals. Remote monitoring of activity and health might counter this impact.

Intensification of dairy production will result in larger herds, more year-round milking, robotic milking, use of housing and yards year round, and total mixed-ration feeding. Larger herds mean longer distances to walk to and from the dairy shed, and more lameness and less time to spend on self-maintenance activities such as grooming. Holding and feeding dairy cows on yards will cause an increase in lameness and mastitis and perhaps an increase in agonistic behaviour but will reduce time spent walking. Intensification of sheep production will involve increased flock size, increased fecundity, breeding from hoggets, and breeding ewes all year round. Housing during lambing might be considered appropriate, as would feeding to lift milk yields. Increased fecundity with an increase in triplets will increase lamb mortality rates, but housing ewes, when managed well, will result in reduced lamb mortality. Intensification of lamb finishing will be by improved nutrition. Intensification of beef production will include more breeding of heifers at 15 months, and more problems with dystocia.

Intensification of pastoral production will have positive and negative effects on animal welfare. The balance will be determined by the quality of management and stockmanship, and the pressure on businesses to be profitable.  相似文献   
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73.
AIMS: To quantify the range of attitudes and perceptions of cattle practitioners to painful procedures and conditions in cattle, to identify some of the demographic factors affecting those attitudes and perceptions, and to compare results from veterinarians based in New Zealand with those from the United Kingdom (UK) and Europe.

METHODS: A questionnaire, based on one used for similar surveys in Europe, was sent to all 455 members of the Society of Dairy Cattle Veterinarians (DCV) of the New Zealand Veterinary Association. This questionnaire included a section on demographic data, e.g. gender, year of graduation, and preveterinary school background, and a section which asked the respondents to rate on a scale of 1 to 10 how painful they thought 24 procedures and conditions would be without any analgesia.

RESULTS: A total of 166 questionnaires were returned, a response rate of 37%. From the range of procedures and conditions outlined in the questionnaire, those perceived as most painful were claw amputation, then Caesarean section, followed by surgery for left-displaced abomasum (LDA). The two least painful were mastitis with milk clots only, and the effect on a calf of dystocia.

There were significant differences between the pain scores assigned by men and women and by respondents who had graduated in different decades. Female respondents and more recent graduates tended to give a higher pain score for most conditions. These effects remained, even after the potential interaction between age and gender had been assessed. The effect on pain score of either background or time spent treating cattle was much less marked than the effect of age and gender.

Overall, the results were very similar to results from similar surveys undertaken in the UK and Europe.

CONCLUSIONS: The responses to this survey indicate that, as in the UK and Europe, dairy cattle practitioners in New Zealand have a wide range of attitudes to pain in cattle. The estimates of the severity of pain were subjective, but such a survey allows the majority opinion of a considerable number of informed assessors to be quantified.

CLINCAL RELEVANCE: The wide range of results suggests that more needs to be done to disseminate up-to-date knowl- edge of pain in cattle to veterinarians to ensure they provide appropriate levels of analgesia. In particular, the baseline data from this study can be used by practitioners to identify whether they are underestimating pain in cattle and, if they are, to assess whether they are using analgesia appropriately. Additionally, this dataset provides an informed and independent assessment of the pain associated with husbandry procedures, and could be used to better guide legislation concerning pain control of such procedures.  相似文献   
74.
Abstract

CASE HISTORIES: Three dogs, aged between 11 and 20 weeks, were presented with unilateral forelimb lameness, with an associated bony prominence on the lateral elbow.

CLINICAL FINDINGS AND DIAGNOSIS: Radiographs revealed a caudolateral luxation of the radial head in all cases, consistent with a diagnosis of suspected congenital luxation of the radial head. Surgical reduction and stabilisation involved open reduction of the radial head, and in two cases the use of a trans articular pin.

CLINICAL RELEVANCE: Congenital luxation of the radial head is an uncommon condition that has conflicting reports in the literature regarding its cause, heritability, breed predisposition, treatment and prognosis. The three cases here occurred in young dogs of English Bull Terrier, Jack Russell Terrier, and Staffordshire Bull Terrier breeds. Surgical reduction and stabilisation provided successful outcomes, in all cases. Only six cases of congenital luxation of the radial head managed surgically have previously been reported in the literature.  相似文献   
75.
76.
AIMS: To explore and validate the utility of rumen endoscopy for collection of rumen papillae for gene expression measurement.

METHODS: Four adult Coopworth ewes were fasted for either 4 or 24 hours. Animals were sedated, placed in a dorsally recumbent position at 45 degrees with the head upright, and an endoscope inserted via a tube inserted into the mouth. Biopsies of rumen papillae were taken from the ventral surface of the rumen atrium under visual guidance. Two biopsies were collected from one of the animals that had been fasted for 4 hours, and three from one of the animals that had been fasted for 24 hours. Video of the rumen atrium and reticulum was also collected. The animals recovered uneventfully. Biopsies were subsequently used for extraction and sequencing of mRNA.

RESULTS: The ventral surface of the rumen atrium was accessible after 4 hours off pasture, but a larger region was accessible after 24 hours of fasting. Sedation allowed access for endoscope use for around 5 to 10 minutes after which increased saliva flow was noted. Rumen papillae biopsies were easily collected, with samples from a variety of sites collected in the ~10 minute time window. High quality RNA was obtained for stranded mRNA sequencing. Of the resulting reads, 69–70% mapped uniquely to version 3.1 of the ovine genome, and 48–49% to a known gene. The rumen mRNA profiles were consistent with a previously reported study.

CONCLUSIONS: This method for obtaining rumenal tissue was found to be rapid and resulted in no apparent short or long term effects on the animal. High quality RNA was successfully extracted and amplified from the rumen papillae biopsies, indicating that this technique could be used for future gene expression studies. The use of rumen endoscopy could be extended to collection of a variety of rumen and reticulum anatomical measurements and deposition and retrieval of small sensors from the rumen. Rumen endoscopy offers an attractive and cost effective approach to repeated rumen biopsies compared with serial slaughter or use of cannulated animals.  相似文献   

77.
Although Thiobacillus ferrooxidans and Leptospirillum ferrooxidans are widely considered to be the microorganisms that control the rate of generation of acid mine drainage, little is known about their natural distribution and abundance. Fluorescence in situ hybridization studies showed that at Iron Mountain, California, T. ferrooxidans occurs in peripheral slime-based communities (at pH over 1.3 and temperature under 30 degreesC) but not in important subsurface acid-forming environments (pH 0.3 to 0.7, temperature 30 degrees to 50 degreesC). Leptospirillum ferrooxidans is abundant in slimes and as a planktonic organism in environments with lower pH. Thiobacillus ferrooxidans affects the precipitation of ferric iron solids but plays a limited role in acid generation, and neither species controls direct catalysis at low pH at this site.  相似文献   
78.
79.
A critical period of early gestation in the mare involves the immobilization (fixation) of the encapsulated conceptus at around days 16–17. We compared the major proteins in the normal equine embryonic capsule and endometrial secretions around the period of fixation with those from pregnancies in the process of termination induced by administration of an analogue of prostaglandin F (PGF). Uterocalin and β2-microglobulin (β2M) associated with the embryonic capsule were proteolytically converted to smaller forms during the fixation period. These conversions were similar in conceptuses from control and treated mares. A 17 kDa cationic protein identified as a secretory phospholipase A2 (sPLA2) type IIA was detected bound to normal capsules but increased substantially in response to PGF. Two forms of uteroglobin were distinguished by partial amino acid sequences of ∼6 kDa bands in flush fluids from normal pregnant uteri. After administration of PGF one immunoreactive form of uteroglobin was preferentially increased. These studies demonstrate that failure of pregnancy in this model is associated with an increase in secretory phospholipase in the capsule and a change in the forms of uteroglobin in the uterine secretions.  相似文献   
80.
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