Oetting-Neumann Pamela, Rohn Karl, Hoedemaker Martina
Tierarztl Prax Ausg G Grosstiere Nutztiere. 2018 Feb;46(1):13-21. doi: 10.15653/TPG-170544. Epub 2018 Feb 21.
Determination of the frequency of subclinical hypocalcaemia, increased lipomobilisation and subclinical ketosis as problems in dairy herds and identification of possible risk factors.
Information was obtained from 51 dairy farms on husbandry, feeding, management of the cows and heifers, animal health and prophylactic treatments using a questionnaire. Blood samples from 20% of the cows and 30% of the heifers of each farm (= herd sample) were collected in the week ante partum (a. p.) for determination of serum calcium (Ca), magnesium (Mg), phosphorus (P) and non-esterified fatty acids (NEFA) concentrations and in the week post partum (p. p.) for measurement of serum β-hydroxybutyrate (BHB) concentration. For evaluation of the herd sample results, the percentage of animals with a laboratory value above a determined threshold value for the various parameters was calculated. When the percentage exceeded a certain threshold (alert) level, a herd problem was assumed. Alert levels from the literature and adapted levels were used.
For minerals, an adapted alert level of 10% was taken as a basis. In cows, the alert level for Ca, Mg, P (too low) and P (too high) was exceeded in 13.7%, 13.7%, 25.7% and 7.8% of the herd samples, respectively. NEFA (a. p.) and BHB (p. p.) had an adapted alert level of 30%. For NEFA, the alert level was exceeded by cows and heifers on 47.1 % and 51.0% of the farms, respectively. For BHB, the alert level was exceeded by cows and heifers on 33.3% and 13.7% of the farms, respectively. As risk factors, a too large group size for the transition cows (Ca, Mg), pasturing (Ca, BHB), one phasic feeding of dry cows (Mg, BHB) and a lack of a separated dry cow area (BHB) were identi fied. Risk factors for the heifers were no pasturing of the young stock (NEFA) and a low frequency of pushing up the diet in the feed bunk (BHB).
Subclinical ketosis in cows and an increased lipomobilisation in heifers were frequent herd problems in the dairy herds studied and were asso ciated with husbandry, feeding and management. Therefore, these herd problems should be handled intensively in veterinary herd health programs with the aim to establish effective preventive measures.
确定亚临床低钙血症、脂肪动员增加和亚临床酮病在奶牛群中的发生频率，并识别可能的风险因素。
通过问卷调查从51个奶牛场获取有关饲养管理、奶牛和小母牛的喂养、动物健康及预防性治疗的信息。在产前一周（a.p.）采集每个农场20%的奶牛和30%的小母牛的血样（即牛群样本），用于测定血清钙（Ca）、镁（Mg）、磷（P）和非酯化脂肪酸（NEFA）浓度；在产后一周（p.p.）采集血样，用于测定血清β-羟基丁酸（BHB）浓度。为评估牛群样本结果，计算各参数实验室值高于既定阈值的动物百分比。当该百分比超过特定阈值（警戒）水平时，则认为存在牛群问题。采用了文献中的警戒水平及调整后的水平。
对于矿物质，以10%的调整警戒水平为基础。在奶牛中，牛群样本中Ca、Mg、P（过低）和P（过高）的警戒水平分别被超过的比例为13.7%、13.7%、25.7%和7.8%。NEFA（a.p.）和BHB（p.p.）的调整警戒水平为30%。对于NEFA，分别有47.1%的农场的奶牛和51.0%的农场的小母牛超过了警戒水平。对于BHB，分别有33.3%的农场的奶牛和13.7%的农场的小母牛超过了警戒水平。作为风险因素，确定为过渡奶牛群体规模过大（Ca、Mg）、放牧（Ca、BHB）、干奶牛一次性饲喂（Mg、BHB）以及缺乏单独的干奶牛区域（BHB）。小母牛的风险因素为幼畜不放牧（NEFA）和饲料槽中推料频率低（BHB）。
在所研究的奶牛群中，奶牛的亚临床酮病和小母牛脂肪动员增加是常见的牛群问题，且与饲养管理、喂养有关。因此，在兽医群体健康计划中应重点处理这些牛群问题，以建立有效的预防措施。
