畜牧场污水处理简易工艺探究

文章就厌氧-好氧、水生植物塘污水处理工艺，从工程实践出发，阐述该工艺所需设施及功能，并认为随着畜牧场规模化、集约化程度的提高，该工艺具有较大使用价值。     

奶牛场污水处理和循环利用模式研究

试验对一个南方奶牛场的排污水进行沼气发酵和沉淀处理,利用沼气能源水泵回抽沉淀后的污水冲洗栏舍,初步探索奶牛场污水处理和循环利用模式.结果表明,奶牛场排污水经过沼气发酵和沉淀处理后,五日生化需氧量、化学需氧量、氨氮浓度、粪大肠菌群数和蛔虫卵数指标分别降低了64.0%、66.8%、65.9%、54.2%和26.5%,牛场平均每年节约用水约46.6%.     

规模奶牛饲养污粪处理工艺

主要讲述了规模奶牛饲养的污粪处理工艺——生物处理法,只有采取切实可行的治理奶牛粪污措施以减少污染,达标排放,才能使养殖业走可持续发展道路。     

规模奶牛饲养污粪处理工艺

主要讲述了规模奶牛饲养的污粪处理工艺--生物处理法,只有采取切实可行的治理奶牛粪污措施以减少污染,达标排放,才能使养殖业走可持续发展道路.     

规模化奶牛场粪便好氧堆肥发酵研究

利用牛粪堆肥是科学、合理地处理和利用牛粪的有效措施。以新鲜牛粪和稻壳为发酵原料,借助翻堆通风方式进行牛粪好氧发酵试验。A组将牛粪与稻壳按4:1的比例混合,添加3‰发酵菌剂;B组在牛粪中直接添加3‰发酵菌剂;C组仅为牛粪发酵,作为对照。结果表明:(1)A组堆肥的C/N比提高到25.48∶1。堆肥含水率、有机质、C/N比值随堆肥过程呈下降趋势,下降由快到慢的依次为A、B、C组。A、B组C/N比降低到16∶1以下分别在堆肥第28、35d,而C组在第35dC/N比仍为17.40∶1。3个组pH均呈先升后降的趋势。(2)总腐殖酸的含量随堆肥过程呈下降趋势,下降幅度A、B两组大于C组;但总腐殖酸占总有机碳比率呈增加趋势,A、B、C 3组发酵前后对比分别提高了40.28%、23.44%、21.67%。(3)堆肥后A、B、C组分别在第5、9、11d温度上升到55℃以上,且维持55℃以上达到25、18、14d。(4)经35d发酵处理后,A、B、C 3组的堆肥有机质、pH、重金属、总养分均符合有机肥标准NY525—2012。综合各项物理化学指标,添加稻壳和发酵菌剂有利于牛粪的腐熟。     

某保健品企业生产污水处理工艺浅析

某保健品有限公司采用气浮-水解酸化-好氧氧化工艺对生产污水进行处理,处理后出水满足广东省《水污染排放限值》(DB44/26-2001)第二时段二级排放标准,通过从方案选择、工艺设计及运行结果等方面对此工程进行介绍。     

SBR污水处理工艺技术分析

对SBR工艺进行简单的介绍,分析它在使用上的优点和局限性。分析SBR污水处理工艺的运行和管理技术,并对SBR日常使用中应注意的问题进行分析。     

我国规模化养殖场污水处理现状

<正>近年来,规模化畜禽养殖业的环境污染问题日益突出,本文对我国规模化畜禽养殖场污水处理现状及存在的环境污染问题进行了分析,并提出规模养殖场污水污染防治的措施与对策,以期为全面推动我国规模化畜禽养殖场污水防治工作提供参考。随着我国经济的发展、人民生活水平的提高,畜禽产品消费数量逐年上升,肉类、禽蛋和牛奶的消费量以平均每年近10%的速度增长,畜禽产品的需求越来越大。20世纪80年代后期,我国畜禽养殖业得到了迅速发展,     

Disease in 27 Norwegian dairy goat farms

A combination of field registrations and laboratory examinations was used to describe the distribution, morbidity and mortality of disease among dairy goats in the western part of Norway.     

Stray voltage on Michigan dairy farms

Stray voltage investigations were performed on 59 Michigan dairy farms at the request of dairymen, veterinarians, and county extension agents. On 32 farms, sources of stray voltage were detected. When the voltage exceeded 1 volt alternating current, there were increased numbers of dairy cows that had abnormal behavior in the milking facility and increased prevalence of clinical mastitis. Recovery from the stray voltage-induced abnormalities was related to the type of abnormality and the magnitude of the exposure voltage.     

A descriptive analysis of the foot lesions identified during veterinary treatment for lameness on dairy farms in north Taranaki

AIM: To analyse the records made during routine veterinary treatment of lame cows, to identify the types of lesions causing lameness of dairy cows in north Taranaki, their relative prevalence and distribution, and some of the cow-associated factors which affect these parameters. METHODS: Data concerning cow age and breed, lesion type, lesion site, and whether the examination was a revisit were collected from records of veterinary visits between December 1995 and July 2007. Data were analysed on a single- or two-factor basis, using chi(2) and, where suitable, calculation of OR. RESULTS: The total number of individual cow treatments recorded was 4,488. The most commonly recorded lesion was white-line disease (WLD) (42% of diagnoses at first examination), and the second was sole injury (29%). Heifers accounted for 19% of cases, similar to the expected replacement rate. Jerseys accounted for 18% of cases, lower than the proportion of purebred Jerseys in the region (27%). There was a significant effect of age and breed on the prevalence and distribution of lesions. There were also significant differences between lesion types in their location, which were also influenced by breed and age. CONCLUSIONS: This study provided a comprehensive overview of the lesions causing lameness in dairy cattle in north Taranaki, and identified some of the factors which influence the development of lesions. More research is needed to better establish the aetiology and pathogenesis of lameness in cattle under New Zealand conditions. CLINICAL RELEVANCE: This study provides baseline data with which veterinarians can compare their results to identify significant patterns on specific farms, which will suggest specific causal factors for lameness on those farms and thus better guide prevention programmes.     

A survey to identify economic opportunities for smallholder dairy farms in Bangladesh

Identified economic opportunities for planning interventions greatly increase farmers’ compliance with an extension programme. We investigated opportunities for interventions to increase dairy farmers’ income in four areas of Bangladesh, including the districts of Mymensingh, Khulna-Satkhira, Sirajgonj-Pabna and Chittagong. The data were collected from 1440 dairy farms at a one-day visit and were summarized as the difference between management targets and each herd’s calculated management indices. The average number of lactating cows, feed cost as a percentage of income from milk, milk sold as percentage of milk produced, lactating cows as a percentage of mature cows, and lactating cows as a percentage of total cattle varied from 1.5 to 3.4, from 52.5% to 92.1%, from 78.7% to 92.6%, from 81.9% to 86.7% and from 34.3% to 37.7%, respectively. The average age at first calving, calf production interval, lactation length, and milk production were 35.0–44.3 months, 14.0–17.6 months, 249–286 days and 3.5–7.2 litres, respectively, depending on the locality. The average cost for producing 100 litres of milk was 18.9–35.1 US dollars. The production cost increased when daily milk production per cow decreased (r² = 0.43–0.55). Management improvements directed towards increasing average milk production per cow per day, increasing lactation length, decreasing age to first calving, and decreasing calf production interval could expect to yield an average income increase up to a range of 676.3–1730.6 US dollars depending on the milk-producing area.     

A longitudinal study of Neospora caninum infection on three dairy farms in Brazil

Neospora caninum is an apicomplexan protozoan parasite that is one of the most important infectious causes of abortion in both dairy and beef cattle in many countries. The objectives of this longitudinal study were to determine the prevalence, rates of vertical and horizontal transmission of N. caninum and hazard for culling of N. caninum-seropositive animals in three Brazilian dairy herds. Blood samples from all animals were collected nine times at each of the three farms over a two-year period. Serum was tested for antibodies against N. caninum using the indirect fluorescent antibody test with a cutoff value of 1:100. The percentage of N. caninum-positive samples at each sampling time ranged at Farm I from 3.32% to 11.71%, at Farm II from 3.90% to 22.06% and at Farm III from 3.90% to 22.06%. The number of positive serological reactions varied in relation to the number of repeated samples taken from individual animals at each farm. In all herds, there was a high degree (P<0.05) of association between the N. caninum serological status of dams and daughters. The seropositive conversion rate was estimated as 0.37%, 3.00% and 6.94% per 100 cow-years at Farms I, II and III, respectively. The seronegative conversion rate was estimated as 31.58% and 11.11% per 100 cow-years at Farms I and III, respectively. In all herds, there was no difference (P>0.05) in the culling rate between the cattle that were seropositive cattle and seronegative for N. caninum infection. The results from this study confirm the importance of vertical transmission in the epidemiology of N. caninum. Although a few positive seroconversions indicated horizontal transmission, it does not appear to be the major route of infection for N. caninum.     

Eimeriosis in dairy cattle farms in Morogoro municipality of Tanzania

Coccidial oocysts were detected in 35% of 445 cattle in four medium-scale and 20 small-scale dairy farms in Morogoro municipality, Tanzania. The highest prevalence (56%) was observed in animals aged between 5 and 18 months, whereas lower prevalences were observed in calves (29%) aged between 12 days and 4 months and adults (30%). No coccidial oocysts were detected in calves less than 12 days old. The oocyst output was high in calves, followed by weaners; adults had the lowest oocyst output. The number of oocysts per gram of faeces was significantly higher (P < 0.001) in diarrhoeic animals than in non-diarrhoeic animals, and more so in young calves. Eimeria species infecting the animals included Eimeria bovis (68%) and Eimeria zuemii (57%), Eimeria ellipsoidalis (25%), Eimeria cylindrica (23%), Eimeria auburnensis (22%), Eimeria alabamensis (12%) and Eimeria subspherica (5%). Mixed infections involving two or three species were common. Our findings indicate that eimeriosis is common in cattle in Morogoro municipality.     

对四川奶牛隐性乳房炎的调查研究

本文采用美国加利福尼亚快速诊断法(CMT法)对四川四家大型奶牛场(A、B、C、D)96头泌乳奶牛的360个乳区进行隐性乳房炎的检测,对患隐性乳房炎的奶牛及其乳区的阳性率进行了样本百分数差异显著性检验,并对患隐性乳房炎奶牛的胎次、日产奶量、年龄与发生率的关系进行了相关性检验。结果得出:被检奶牛隐性乳房炎的头发生率为25%,乳区发生率为9.17%;奶牛隐性乳房炎发生率和泌乳奶牛年龄、胎次呈显著正相关,奶牛隐性乳房炎发生率对日产奶量也有显著影响。     

Strategies for reduced antibiotic usage in dairy cattle farms

The need for antibiotic treatments in dairy cattle farms can be reduced by a combined intervention scheme based on: (1) timely clinical inspections, (2) the assessment of animal-based welfare parameters, and (3) the use of predictive laboratory tests. These can provide greater insight into environmental adaptation of dairy cows and define animals at risk of contracting disease. In the long-term, an improved disease control justifies the adoption of such a combined strategy. Many antibiotic treatments for chronic disease cases are often not justified with a cost/benefit analysis, because the repeated drug administration does not give rise to the expected outcome in terms of animal health. In particular, compared with untreated cases, antibiotics may not lead to greater cure rates for some forms of mastitis. Lastly, a substantial reduction of antibiotic usage in dairy farms can be achieved through the proper use of immunomodulators, aimed at increasing immunocompetence and disease resistance of cows.     

The effects of early treatment for hindlimb lameness in dairy cows on four commercial UK farms

An 'early threshold' protocol for treating cows within 48h of being detected lame in one or more hind limbs at fortnightly mobility scoring was tested on a randomly selected group of cattle on four commercial dairy farms. The outcomes of the early threshold treatment for first cases of lameness were compared with those of the farmers' conventional approach to treatment. The early threshold schedule resulted in a much shorter time to treatment than the conventional approach, for which the median time from the cow first being scored lame to treatment was 65days. The early threshold group presented with less severe foot lesions and cattle were less likely to be selected for further treatments by the farmer than conventionally treated cows. Early threshold treatment reduced the prevalence of lameness 4weeks after treatment, compared with controls. A clear effect of the early treatment on milk yield was not detected.