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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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We investigated crop load and water stress effects on diurnal stem extension growth of field-grown peach (Prunus persica (L.) Batsch) trees. Neither the presence of fruit nor reduced irrigation significantly altered the timing of diurnal fluctuations in stem growth rate. Stems with subtending fruit had significantly reduced growth compared to stems with no subtending fruit. Crop load had no significant effect on relative stem extension rates and the majority of the reduction in absolute growth was the result of a smaller zone of elongation in fruit-bearing stems than in stems with no subtending fruit. Fruit removal did not increase growth rates within 24 h. When irrigation was reduced, the length of the stem elongation zone and total daily stem growth were significantly decreased relative to well-irrigated controls and the decreases were highly correlated with stem water potential. Compared with well-irrigated controls, relative stem extension rates of water-stressed trees were reduced at several times during the 24-h period, but the degree of reduction was not proportional to the difference in stem water potentials between the treatments.  相似文献   
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Deafferentation in monkeys: effect on conditioned grasp response   总被引:1,自引:0,他引:1  
A preliminary technique was developed for conditioning grasp response in monkeys, for use in studying the effect of damage to the central nervous system on skilled movement. That subjects were able to learn this response with a deafferented hand, in the absence of vision, indicated that purposive movements of the distal musculature are less under the control of peripheral feedback than had been generally believed.  相似文献   
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Sea urchin skeletal elements are composed of single crystals of calcite. Unlike their synthetic counterparts, these crystals do not have well-developed cleavage and are consequently much more resistant to fracture. This phenomenon is due in part to the presence of acidic glycoproteins occluded within the crystals. By means of x-ray diffraction with synchrotron radiation, it is shown that the presence of the protein in synthetic calcite only slightly decreases the coherence length but significantly increases the angular spread of perfect domains of the crystals. In biogenic calcite, the coherence length is 1/3 to 1/4 as much as that in synthetic calcite and the angular spread is 20 to 50 times as wide. It is proposed that the presence of macromolecules concentrated at mosaic boundaries that are oblique to deavage planes is responsible for the change in fracture properties. These results may be important in the material sciences, because of the unusual nature of this material, namely, a composite based on the controlled intercalation of macromolecules inside single-crystal lattices.  相似文献   
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Evidence from determinations of crystal structure relating to the shortening of carbon-oxygen bonds in the anomeric position in pyranose sugars is presented. There is a high degree of probability that the C(1)-O(1) bond is shortened by about 0.04 A relative to the other C-O single-bond lengths, except in the case of an axially oriented glycosidic group where there is evidence of a distinction between the two ring C-O bonds.  相似文献   
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In memory consolidation, the memory trace stabilizes and becomes resistant to certain amnesic agents. The textbook account is that for any memorized item, consolidation starts and ends just once. However, evidence has accumulated that upon activation in retrieval, the trace may reconsolidate. Whereas some authors reported transient renewed susceptibility of retrieved memories to consolidation blockers, others could not detect it. Here, we report that in both conditioned taste aversion in the rat and fear conditioning in the medaka fish, the stability of retrieved memory is inversely correlated with the control of behavior by that memory. This result may explain some conflicting findings on reconsolidation of activated memories.  相似文献   
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