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1.

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.
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DNA barcoding has been proposed as a method for species identification. However, this method has been criticised for its over-reliance on a single mitochondrial gene. In this study, four mitochondrial gene regions and one nuclear gene region were used to investigate their different abilities to identify tissue associated with museum specimens of Aethomys chrysophilus, Aethomys ineptus and Micaelamys namaquensis. Aethomys chrysophilus and the more recently elevated A. ineptus are indistinguishable on morphological grounds; however, their ranges are largely parapatric with only one syntopic locality currently known. All of the mitochondrial gene regions were able to separate M. namaquensis from A. chrysophilus and A. ineptus, but they varied in their abilities to resolve differences between A. chrysophilus and A. ineptus. The sequence results identified a specimen from KwaZulu-Natal that was misclassified and should have been identified as A. ineptus. Seven specimens that had not been reclassified following the elevation of A. ineptus to species level were identified as A. ineptus. Individuals of A. chrysophilus from Malawi could not be classified as either A. chrysophilus or A. ineptus, and may be a hybrid or a new, distinct species. This study indicates that DNA barcoding may be used to separate M. namaquensis from A. chrysophilus and A. ineptus, and although it was not able to separate A. chrysophilus and A. ineptus, it did indicate specimens from Malawi may be a new cryptic species.  相似文献   
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This study evaluated the application of stable isotopes of carbon as an alternative and more accurate method to determine gastrointestinal transit time (GTT) in fish by comparing it to the inert marker method. The stable isotope method detects alterations of the normal carbon flow in a biological system by analyzing naturally occurring isotopes of carbon, contrary to studies based on conventional techniques that apply external markers to the diet to determine GTT through visual observation of the color change in feces. Therefore, 320 pacu, Piaractus mesopotamicus juveniles were reared in 32 tanks under two different temperatures (25 and 29 C). The pacu juveniles received two different diets, one based on ingredients derived from C3 photosynthetic cycle plants and the other based on C4 plant ingredients, both containing titanium oxide (TiO2) as a marker. After 40 d, the isotopic signature of the diets was changed, and the marker was replaced by chromic oxide (Cr2O3). In the isotopic technique, the feces were analyzed to determine the exchange in the isotopic ratio of carbon δ13C. Both methods found that GTT was faster (nearly 6 h) in fish at 29 C when using the C4/C3 feeding strategy and slower in fish at 25 C using the C3/C4 strategy (15 h by inert marker and 18 h by the isotopic method). In conclusion, GTT determination in pacu juveniles using the stable isotope technique exhibits the same accuracy obtained with the inert marker method at temperatures suitable (nearly 29 C) for the metabolism of these animals.  相似文献   
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SUMMARY: During 1988, 2 farmers in the Bega district agisted pregnant cattle in the Hunter Valley of New South Wales. On return to the district to calve, 54% of calves from herd 1 and 30% of calves from herd 2 were affected with congenital arthrogryposls or hydranencephaly caused by Akabane virus infection. Field observations and laboratory findings from this outbreak are presented, illustrating the danger of moving immunologlcally naive animals into areas where Akabane virus is endemic.  相似文献   
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A technique is described for the visual examination and biopsy sampling of the affected organ in canine liver and pancreatic dysfunction.
Résumé . On a décrit une technique pour l'examen visuel et la biopsie d'essais de l'organe affecté dans le foie du chien et le mauvais fonctionnement du pancreas.
Zusammenfassung . Man hat eine Technik beschrieben, für die Sichtprobe und die Biopsie-Probenahme des angegriffenen Organs in der Hundeleber und in der Bauchspeichelschlechtfunktion.  相似文献   
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Items for inclusion in this section should be sent at least 6 weeks prior to publication date, which is approximately 18-20th of each month, to the Editor, Journal of Small Animal Practice, 142 North Road, Hertford, Herts., England.  相似文献   
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