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71.
OBJECTIVE: To determine sheep farmers' attitudes to and beliefs about ovine footrot, and to improve their knowledge about the diagnosis, control and eradication of this disease. METHOD: Eighteen workshops, involving 291 farmers, were conducted across Victoria in the spring of 1996. The workshops were designed as small-group discussions with a maximum attendance of 20 farmers to encourage active participation. All participants completed questionnaires before each workshop and 12 to 40 weeks after the last workshop. RESULTS: Before the workshops the farmers had a poor understanding of the principles of diagnosis, control and eradication of footrot. For example, only 50% knew the footrot organism survived in soil for less than 7 days, over two-thirds did not know the reason for paring sheep's feet during an eradication program, and only 31% realised cattle were a potential source of footrot infection for sheep. After the workshops, understanding about footrot was significantly improved; 87% said Dichelobacter nodosus survived in soil less than 7 days, 71% knew the reason for paring sheep's feet and 64% realised that cattle were a potential source of footrot infection. As well as improved knowledge, change of attitude among farmers is fundamentally important if virulent footrot is to be successfully controlled and eradicated. The workshops successfully initiated this process; 40% of farmers thought the workshops changed their attitudes to footrot, while 37% said they gained an increased understanding of other people's opinions about the disease. CONCLUSION: Farmers' poor understanding of ovine footrot is a constraint to the programs aimed at controlling this disease. Small group workshops may be an effective way to influence farmers' attitudes and beliefs, and could facilitate the effectiveness of regulatory disease control programs. 相似文献
72.
Isam T. KADIM Osman MAHGOUB Waleed AL‐MARZOOQI Samera KHALAF Shadia S. H. AL‐SINAWI Issa AL‐AMRI 《Animal Science Journal》2010,81(3):352-361
The effects of transportation and electrical stimulation (90 V) on physiological, histochemical and meat quality characteristics of two breeds of Omani goats were assessed. Twenty 1‐year‐old male goats from each breed (Batina and Dhofari) were divided into two groups: 3 h transported during the hot season (42°C day time temperature) and non‐transported. Animals were blood‐sampled before loading and prior to slaughter. Electrical stimulation was applied 20 min postmortem to 50% randomly selected carcasses of both breeds. Temperature and pH decline of the Longissimus was monitored. Ultimate pH, shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and colour were measured from samples of Longissimus dorsi muscles. Electrical stimulation and transportation had a significant effect on most biochemical and meat quality characteristics of Longissimus dorsi. The transported goats had higher plasma cortisol (P < 0.01), adrenaline, nor‐adrenaline and dopamine concentrations (P < 0.05) than non‐transported goats. Electrical stimulation resulted in a significantly (P < 0.05) more rapid muscle pH fall during the first 12 h after slaughter. Muscles from electrically‐stimulated carcasses had significantly (P < 0.05) longer sarcomeres, lower shear force value, a lighter colour (higher L* value), higher expressed juice and myofibrillar fragmentation index than those from non‐stimulated ones. Meat from transported goats had significantly higher pH, expressed juice and shear force, but contained significantly lower sarcomere length and L* values than non‐transported goats. The proportion of the myosin ATPase staining did not change as a function of stimulation, transportation or breed. These results indicated that subjecting goats to transportation for 3 h under high ambient temperatures can generate major physiological and muscle metabolism responses. Electrical stimulation improved quality characteristics of meat from both groups. This indicates that electrical stimulation may reduce detrimental effects of transportation on meat quality of Omani goats. 相似文献
73.
EI Cortés-Gutiérrez F Crespo C Serres-Dalmau AL Gutiérrez de las Rozas MI Dávila-Rodríguez C López-Fernández J Gósalvez 《Reproduction in domestic animals》2009,44(5):823-828
Sperm DNA fragmentation (sDF) is an important parameter to assessing sperm quality. Information about sperm quality is not available for donkeys, especially in some breeds at risk of extinction. The objectives of this research were to test the four commercial variants of sperm chromatin dispersion test (SCD; sperm Halomax test), originally developed to assess sDF in boars, bulls, rams and stallions, in order to scrutinize their applicability in the study of sDF in a donkey breed at risk of extinction (Zamorano-Leonesa), for which there is no specific test available to analyze sperm at present. Only the SCD test, originally developed for stallions, produced stable and consistent results, and was deemed suitable to assess DNA fragmentation in sperm samples from donkeys. Image analysis was used to compare differences between the SCD methodology applied to stallion and donkey semen samples processed under the same experimental conditions. The extent of SCD in the SCD test was approximately 20% lower in donkey sperm than in stallion sperm. Yet, the ratio of chromatin sperm dispersion achieved in fragmented and unfragmented nuclei did not differ significantly between species. These data suggest that a similar protein depletion treatment can cause differences in protein removal in equivalent cells from different species and that sperm chromatin may be organized differently in stallions and donkeys. 相似文献
74.
75.
Dipta DEY Tanzila Ismail EMA Partha BISWAS Sharmin AKTAR Shoeba ISLAM Urmi Rahman RINIK Mahmudul FIROZ Shahlaa Zernaz AHMED Salauddin AL AZAD Ahsab RAHMAN Sadia AFRIN Rezwan Ahmed MAHEDI Md. Nasir Uddin BADAL 《农业科学与工程前沿(英文版)》2021,8(4):603
76.
Objective To measure associations between body weight, growth rate, sex, time of shearing and post-weaning mortality of Merino sheep.
Design Uni- and multivariable survival analyses of sheep mortality during the first year after weaning, using records (n = 3657) from two field experiments conducted in Western Victoria from 1996 to 2003.
Results Overall mortality was 14.3% (range 4.5–26.8%) and mean maximum mortality rate was 29 deaths/1000 weaners/month. Increased mortality risk was associated with decreases in fleece-free body weight and mean weaner growth rate, particularly at low weights and growth rates. Weaners in the lightest weaning weight quintile had a hazard ratio of 3.5, compared with the middle quintile. The hazard ratio for a 2-kg decrease in weaning weight was 1.2 to 1.7 for weaners lighter than 22 kg. The hazard ratio for a reduction in mean weaner growth rate in the first 5 months after weaning of 0.25 kg/month was 1.1 to 6.8 if mean growth rate was less than 1 kg/month, but did not differ significantly from 1 at greater growth rates. The hazard ratio for wether weaners was approximately 1.5 compared with ewe weaners. The hazard ratio for weaners shorn between December and May, compared with unshorn weaners, was 1.2 to 3.5, with the greatest risk difference associated with shearing in March (45 deaths/1000 weaners/month).
Conclusion Improving the body weight and mean growth rate of weaner sheep is likely to reduce post-weaning mortality. Lightweight weaners in a flock should be managed separately from the main portion after weaning. In southern Australia, not shearing spring-born Merino weaners between December and May may assist in reducing overall post-weaning mortality. 相似文献
Design Uni- and multivariable survival analyses of sheep mortality during the first year after weaning, using records (n = 3657) from two field experiments conducted in Western Victoria from 1996 to 2003.
Results Overall mortality was 14.3% (range 4.5–26.8%) and mean maximum mortality rate was 29 deaths/1000 weaners/month. Increased mortality risk was associated with decreases in fleece-free body weight and mean weaner growth rate, particularly at low weights and growth rates. Weaners in the lightest weaning weight quintile had a hazard ratio of 3.5, compared with the middle quintile. The hazard ratio for a 2-kg decrease in weaning weight was 1.2 to 1.7 for weaners lighter than 22 kg. The hazard ratio for a reduction in mean weaner growth rate in the first 5 months after weaning of 0.25 kg/month was 1.1 to 6.8 if mean growth rate was less than 1 kg/month, but did not differ significantly from 1 at greater growth rates. The hazard ratio for wether weaners was approximately 1.5 compared with ewe weaners. The hazard ratio for weaners shorn between December and May, compared with unshorn weaners, was 1.2 to 3.5, with the greatest risk difference associated with shearing in March (45 deaths/1000 weaners/month).
Conclusion Improving the body weight and mean growth rate of weaner sheep is likely to reduce post-weaning mortality. Lightweight weaners in a flock should be managed separately from the main portion after weaning. In southern Australia, not shearing spring-born Merino weaners between December and May may assist in reducing overall post-weaning mortality. 相似文献
77.
华南亚热带作物科学研究所粤西試験站 《土壤学报》1966,14(1):13-21
我国热带地区具有高温多雨、雨量分布不均匀且多暴雨的特点,容易引起水土流失,土壤有机质分解快,养分淋溶流失强烈,因此热带地区的红壤和砖红壤的有机质和速效养分含量都很低。热带经济林木和果园间种绿肥覆盖作物可以保持水土,增进地力,促使主作物速生高产[1,2],而建立牧草基地以发展畜牧业和种植绿肥是增加优质有机肥料来源的有效途径。这样才有可能增施大量有机肥料,不断提高土壤肥力,保证农林作物稳产高产。 相似文献
78.
Composite top- and subsoil samples were collected from the greenhouses in the Al-Balawneh area,Jordan,where intensive greenhouse production system(IGPS) has been practiced since 1998,to study the impact of IGPS on soil quality as measured by the chemical and biological properties to develop a sustainable production system.The study showed that IGPS led to higher electrical conductivity in top- and subsoils compared to an uncultivated soil(control).Quality and amount of irrigation water,lack of efficient drainage,and quantity and types of applied fertilizers were major factors resulting in salt buildup.IGPS resulted in lower total N(TN) and NO3-N in the soil compared to the control.The lower TN was due to crop uptake,microbial immobilization,volatilization,and irregular application of composted animal manure or poultry manure.In contrast,higher residual Olsen-P content was detected in both soil layers of greenhouses than in the control.Residual P was classified as very high in the topsoil layers and sufficient to high in the subsoil layers.Residual available K in the soils of greenhouses was relatively lower than that in the control and it was,however,classified as high to very high.A large increase of Cl and a considerable decrease in the bacterial count were observed in both soil layers of IGPS compared to the control treatment.Economically sustainable soil management practices need to be adopted by farmers to achieve a sustainable and profitable production.This can be accomplished through education,targeted towards the farming community in the central Jordan Valley. 相似文献
79.
Bedrock landsliding is a dominant geomorphic process in a number of high-relief landscapes, yet is neglected in landscape evolution models. A physical model of sliding in beans is presented, in which incremental lowering of one wall simulates baselevel fall and generates slides. Frequent small slides produce irregular hillslopes, on which steep toes and head scarps persist until being cleared by infrequent large slides. These steep segments are observed on hillslopes in high-relief landscapes and have been interpreted as evidence for increases in tectonic or climatic process rates. In certain cases, they may instead reflect normal hillslope evolution by landsliding. 相似文献
80.
The increasing global demand for food production, often causing excessive use of chemical fertilizers, has led to the deterioration of soil health. Immediate action is required to restore soil health in a sustainable manner. This review advocates switching to use of organic matter(manure and compost) that contains vital nutrients for plant growth and helps restore soil health. Humic substances(HSs), derived from degraded plant remains and found ubiquitously in nature,are an important source of o... 相似文献