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Sporidesmin-dosed hoggets which developed photosensitisation were shown to have enlarged adrenal glands and premature involution of the thymus. These sheep also developed high concentrations of plasma cortisol after the onset of photosensitisation. Sporidesmin-dosed sheep which did not show photosensitisation showed less or no adrenal associated changes.  相似文献   
3.
1. The inclusion of 25 g hydrolysed feather meal (HFM) in each kilogram of diet (floor experiment) and 60 g/kg (cage experiment) did not depress performance.

2. Chemical tests indicated 72.5% of the total lysine in HFM was available.

3. Total lysine concentration of 11.3 g/kg diet maximised performance during the period 0 to 34 d.

4. Reduction in dietary methionine content during the period 0 to 34 d from 4.2 g/kg to 3.2 g/kg did not depress performance on diets containing 60 g HFM/kg.

5. The results indicate that at least 57% by weight of the total sulphur amino acid requirement of broilers can be provided by cystine.  相似文献   

4.
1. The ability of Streptococcus faecalis and Streptococcus faecium strains to survive in egg albumen and liquid whole egg before and after laboratory pasteurisation was studied.

2. Pasteurisation of egg albumen caused a decrease in viable cells of less than 10‐fold, while pasteurisation of whole egg caused decreases of more than 100‐fold in only two of the eight strains studied. After growth in whole egg, some strains were more resistant to pasteurisation in whole egg.

3. Strep, faecalis multiplied in raw and pasteurised whole egg but not in egg albumen.

4. Strep, faecium multiplied in raw and pasteurised whole egg only after an initial decline in viability which was not shown by cells adapted to whole egg. Together with storage temperature this affected the number of viable cells after a storage period of 5 d.

5. In raw and pasteurised egg albumen Strep, faecium strains lost viability; this was maximal at 37 °C and more cells survived as the storage temperature decreased.  相似文献   

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7.

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.
  相似文献   
8.
The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   
9.
A 6-month-old Thoroughbred colt was referred to Rossdales Equine Hospital with a recent history of discomfort and inability to protrude the penis whilst urinating, resulting in accumulation of urine within the prepuce. Careful examination and manual palpation revealed a constrictive ring of fibrous tissue at the level of the preputial orifice. With no evidence of trauma or a persistent penile frenulum, a tentative diagnosis of phimosis due to congenital preputial stenosis was made. Exploratory surgery confirmed the diagnosis and surgical transection and release of the fibromuscular ring at three sites allowed the colt to protrude the penis and urinate normally immediately post-operatively. At follow-up examination 11 months later, the colt continued to be able to extrude the penis and urinate conventionally. A slight excess of skin was present at the end of the prepuce but this was only of minor cosmetic concern.  相似文献   
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