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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.
  相似文献   
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4.

Context

Many nearshore species are distributed in habitat patches connected only through larval dispersal. Genetic research has shown some spatial structure of such metapopulations and modeling studies have shed light onto possible patterns of connectivity and barriers. However, little is known about human impact on their spatial structure and patterns of connectivity.

Objectives

We examine the effects of fishing on the spatial and temporal dynamics of metapopulations of sedentary marine species (red sea urchin and red abalone) interconnected by larval dispersal.

Methods

We constructed a metapopulation model to simulate abalone and sea urchin metapopulations experiencing increasing levels of fishing mortality. We performed the modularity analysis on the yearly larval connectivity matrices produced by these simulations, and analyzed the changes of modularity and the formation of modules over time as indicators of spatial structure.

Results

The analysis revealed a strong modular spatial structure for abalone and a weak spatial signature for sea urchin. In abalone, under exploitation, modularity takes step-wise drops on the path to extinction, and modules breakdown into smaller fragments followed by module and later metapopulation collapse. In contrast, sea urchin showed high modularity variation, indicating high- and low-mixing years, but an abrupt collapse of the metapopulation under strong exploitation.

Conclusions

The results identify a disruption in larval connectivity and a pattern of collapse in highly modular nearshore metapopulations. These results highlight the ability of modularity to detect spatial structure in marine metapopulations, which varies among species, and to show early changes in the spatial structure of exploited metapopulations.
  相似文献   
5.
 贮藏蛋白组成是决定小麦加工品质的重要因素。本文调查了我国冬播麦区251份主栽品种和高代品系的高分子量麦谷蛋白亚基(HMW-GS)、低分子量麦谷蛋白亚基(LMW-GS)和1B/1R易位的分布状况,研究了它们与加工品质性状的关系。结果表明,品质较差的HMW-GS N、7+9、2+12和LMW-GS Glu-A3a与Glu-B3j(1B/1R易位)在冬播麦区分布较广,频率分别为39.4%、45.0%、59.8%、37.1%和44.6%。HMW-GS和LMW-GS等位变异对籽粒蛋白质含量影响较小,对SDS沉降值、和面时间与耐揉性的加性和互作效应达1%的显著水平。按位点对加工品质性状的贡献大小,Glu-D1>Glu-B3>Glu-B1>Glu-A3>Glu-A1;就单个亚基而言,Glu-A1位点,1>2*>N;Glu-B1位点,7+8>14+15>7+9;Glu-D1位点,5+10>4+12>2+12;Glu-A3位点,Glu-A3d>Glu-A3a>Glu-A3c>Glu-A3e,Glu-B3位点; Glu-B3d>Glu-B3b>Glu-B3f >Glu-B3j。1B/1R易位对SDS沉降值、和面时间和耐揉性等加工品质性状有显著负面效应。通过选择优质高低分子量麦谷蛋白亚基和淘汰1B/1R易位系,将有助于提高我国小麦的面筋质量。  相似文献   
6.
Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for...  相似文献   
7.
New Forests - Spanish red cedar, Cedrela odorata L. (Meliaceae), is a valuable timber tree in tropical American forests. Existing demand for elite individuals endangers the conservation of...  相似文献   
8.
Twenty-four hour urinary excretion, fractional excretion and the filtered load of calcium and phosphorus were monitored as hyperparathyroidism evolved in a model of progressive canine renal failure. Thirteen beagles of both sexes aged four and a half months were used. Nine of them were subjected to a renal damaging schedule (neomycine, 60 mg/kg/48 h, IM, 32 weeks) in order to induce chronic renal failure leading to secondary hyperparathyroidism (2HPT group). The remaining four were kept as the control group. The experiment was conducted over 32 weeks. Blood and 24 h urine were collected every four weeks. Calcium, phosphorus and creatinine were analyzed. Plasma parathormone and calcitonin were determined at weeks 0, 12, 24 and 32. The level of renal function in the 2HPT animals was reduced to 25% of that of the controls (endogenous creatinine clearance was 0.45 +/- 0.22 mL/min/kg as opposed to 1.81 +/- 0.54 mL/min/kg). Hyperparathyroidism was confirmed by a progressive increase in the levels of the parathyroid hormone. Calcitonin levels were not modified. A tendency to hypocalcaemia was observed, reaching statistically significant levels from the twenty-eighth week of the study, when hyperphosphataemia also became significant. Daily urinary excretion of calcium and phosphorus remained at values considered normal throughout the experiment with no alteration imputable to the impaired renal function. This is explained by the decrease in the filtered load of these elements (in both cases statistically significant from the 24th week on) being associated with an increase in their fractional excretion. Thus, calcium and phosphorus urinary excretion values could be maintained in a normal range up to the end of the experiment, showing that renal calcium handling in dogs with experimentally induced renal failure seems to differ from that observed in human patients.  相似文献   
9.
This paper reports on the genital lesions observed in adult male and female goats from a commercial flock in the Extremadura region of southwestern Spain, following an outbreak of contagious agalactia syndrome caused by Mycoplasma agalactiae and M. putrefaciens. Although both species were isolated from several organs, M. putrefaciens was the only agent isolated from the genital lesions reported here, characterized by desquamative salpingitis and cystic catarrhal metritis in females and by testicular degeneration in males. Mycoplasma putrefaciens was isolated from the testes of only one of the males examined.  相似文献   
10.
Integrated pest management programs for mango must be based on sampling and on economic thresholds, and must take into account the effects of cultural practices, horticultural sprays and disease control on pest and natural enemy interactions. An analysis of the mass of information available on the different mango pests,viz., fruit flies(Bactrocera sp.,Ceratitis sp.,Anastrepha sp.), mango seed weevil(Sternochetus mangiferae), thrips(Frankliniella spp.), gall midges(Procontarinia sp.), scales, mites and mealybugs is given, as well as different examples for future entomological research.  相似文献   
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