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31.
Estimation of milk production losses due to sub-clinical mastitis in dairy cattle in Costa Rica 总被引:1,自引:0,他引:1
Five dairy farms, situated on the slopes of the volcano Poás in the pre-mountain cloud forest ecological zone, Alajuela and Heredia Provinces, Costa Rica, provided data for estimation of the production losses due to sub-clinical mastitis. Within the same farm, cows with proven sub-clinical mastitis were matched with cows without signs of sub-clinical mastitis, according to breed, lactation number and days in lactation. A total of 529 cows were detected with sub-clinical mastitis, of which only 200 could be paired with control cows free of mastitis; each pair was used only once.
Crude milk production losses per cow with sub-clinical mastitis were estimated at 1.56 kg day−1for daily milk yield. Milk production loss per affected quarter due to sub-clinical mastitis was estimated to be 17.6% on average. The decrease in milk production in heifers with sub-clinical mastitis did not differ significantly from the decrease in production in older cows. No significant difference in milk production loss was detected when the data were stratified on parity or the number of quarters affected. 相似文献
32.
B.P.A. Fonseca MS A.L.G. Alves PhD J.L.M. Nicoletti PhD A. Thomassian PhD C.A. Hussni PhD S. Mikail DVM 《Journal of Equine Veterinary Science》2006,26(11):507-516
The object of the current study was to evaluate the efficacy of thermography and ultrasonography in the diagnosis of thoracolumbar lesions in Quarter Horse athletes and associate the different types of lesions found with the athletic modality practiced. Twenty-four horses were admitted to the Surgery Service for Large Animals of the Veterinary and Animal Science Faculty, UNESP, Botucatu, Brazil, with complaints of back problems. All the horses were submitted for physical examinations to confirm the existence of thoracolumbar alterations and then for thermography and ultrasonography. Thermography was used to map the lesioned areas of this region and ultrasonography for lesion characterization. The lesions found were supraspinous desmitis, interspinous desmitis, dorsal intervertebral osteoarthritis, and impingement of the spinous processes or kissing spines. The existence of a relation between the type of event practiced by the horse and the type of lesion found was determined. In horses that competed in the barrel race, a predominance of lesions in the thoracic caudal, thoracolumbar, and cranial lumbar regions occurred, with intervertebral osteoarthritis and interspinous desmitis being the most common. In cutting horses, most of the lesions were observed in the caudal lumbar region, whereas horses competing in reining showed a preferential location for lesions in the middle lumbar, with a predominance of supraspinous desmitis and myositis. Thermography associated with ultrasonography was shown to be efficient in the diagnosis of the thoracolumbar lesions of these horses. 相似文献
33.
C. Thomson D. Archer B. Ahern C. E. Medina-Torres 《Equine Veterinary Education》2020,32(12):e254-e258
This case report discusses a successful partial splenectomy for treatment of a splenic abscess in a horse. A 2-year-old Thoroughbred colt was hospitalised 5 weeks after an episode of severe colic that was followed by gradual weight loss and anorexia, pyrexia for 5 days and dehydration on the day of referral. A large splenic abscess was identified ultrasonographically. Following initial medical treatment, an exploratory laparotomy was performed. Multiple adhesions were released and a partial splenectomy conducted to remove the abscess. Migrant metallic wires penetrating from the small intestine into the splenic parenchyma were found to be the cause for the adhesions and the abscess. This paper summarises the potential advantages of utilising a partial vs. a total splenectomy and highlights the potential complications of these surgical procedure in equines. 相似文献
34.
通过奶牛生产性能(dairy herd improvement,DHI)测定体细胞数,探究奶牛的胎次及其不同泌乳阶段对其乳体细胞数(somatic cell count,SCC)和乳损失量的影响。通过对某养殖场泌乳期奶牛DHI的测定进行分析,结果表明:体细胞评分(somatic cell score,SCS)随奶牛胎次的增加而增加,但SCS在不同胎次的不同泌乳阶段表现有所不同。一胎牛SCS随着泌乳期的延长而增加,前期、中期与后期的SCS呈显著性差异(P<0.05);二胎牛与三胎牛SCS呈现相同变化规律,泌乳前期的SCS较泌乳中期高,而泌乳后期SCS显著高于前2个泌乳阶段(P<0.05)。乳损失量随胎次的增加整体呈现增加趋势,且泌乳早期和泌乳后期乳损失量高于泌乳中期。 相似文献
35.
李莎莎田秀华陈雁飞巩万里 《野生动物》2014,(1):91-94
2011年4—5月,对徐州金桥禽业发展有限公司养殖的赤麻鸭所产的44枚卵进行了人工孵化研究。其中43枚卵受精,出雏35枚,4枚在孵化中期死胚,5枚为27d落盘后啄壳困难而死亡,受精卵的孵化率为81.40%。孵化温度前期为38.5℃;中期为38.2℃;后期为37.8℃,落盘后温度降为37.5℃。赤麻鸭卵鲜重为(79.80±6.72)g,长径为(66.10±2.53)mnq,短径为(46.40±1.45)/mm,卵形指数为1.43±0.06,出雏后的卵壳等剩余物质重(12.60±1.07)g,新生雏鸟重占鲜卵重的(67.20±3.71)%。卵总失重率为17%。孵化期间的卵重(Y)与孵化天数(x)之间的线性方程为Y=一0.9071x+81.019(R2=0.9997,P〈0.01),根据卵失重方程可以比较准确地推算出赤麻鸭卵的孵化天数。 相似文献
36.
Background
It has been shown that the prevalence of both clinical attachment loss (CAL) ≥1 mm and pocket probing depth (PPD) ≥4 mm is relatively high even in younger dogs, but also that only a minority of the dogs have such clinical signs of periodontal disease (PD) in more than a few teeth. Hence, a minority of dogs carry the major PD burden. These epidemiological features suggest that screening for PD in larger groups of dogs, allowing for rapid assessment of treatment planning, or for the selection of dogs with or without PD prior to be included in experimental trials, should be possible. CAL is the central variable in assessing PD extent and severity while PPD is the central variable used in treatment planning which make these two variables obvious in a screening protocol with the dual aim of disease identification and treatment planning. The main purpose of the present study in 98 laboratory Beagle dogs was to construct a fast, simple and accurate screening tool, which is highly sensitive for the identification of dogs with PD.Results
Examination of the maxillary P4, P3, P2, I1 and C would, in this population, result in the identification of 85.5% of all dogs and 96% of all teeth positive for CAL ≥1 mm, and 58.9% of all dogs and 82.1% of all teeth positive for PD ≥4 mm.Examination of tooth pairs, all C’s, maxillary I2, M2 and the mandibular P4 would, in this population result in identification of 92.9% of all dogs and 97.3% of all teeth positive for PD ≥4 mm, and 65.5% of all dogs and 83.2% of all teeth positive for CAL ≥1 mm. The results presented here only pertain to the present study population.Conclusions
This screening protocol is suitable for examination of larger groups of laboratory Beagle dogs for PD and our findings indicate that diseased dogs are identified with a high degree of sensitivity. Before this screening can be used in clinical practice, it has to be validated in breeds other than Beagle dogs and in populations with larger age variation. 相似文献37.
朱晓华 《中国生态农业学报》2003,11(2):139-140
简析了我国农业气象灾害影响地域广、区域差异明显以及发生频率逐渐变大、灾情逐渐加重等基本特征,揭示了导致我国农业气象灾害频繁发生以及灾情巨大的原因,并提出应改变传统灾害管理体制,依靠科技进步和加强农业灾害保险建设等减灾对策。 相似文献
38.
为研究减少在番茄茎秆好氧堆肥过程中氮素损失的途径,提高堆肥品质,以粉碎的番茄茎秆为原料,按物料干重分别加入5%的腐殖酸(T1)、氯化钙(T2)和过磷酸钙(T3),同时以不进行任何添加的堆体作为对照(CK),进行45 d的好氧堆肥试验。结果表明:3种添加剂均可降低堆肥过程中的氮素损失,同时减少了NH3的挥发量;堆肥结束时,CK、T1、T2和T3处理的氮素损失率分别为18.04%、15.00%、12.65%和14.05%,累计NH3挥发量为CK(1 648.11 mg/kg)>T1(1 330.35 mg/kg)>T3(995.35 mg/kg)>T2(528.11 mg/kg)。其中,添加氯化钙的处理保氮效果最好,与对照相比,氮素损失率低至12.65%,NH3挥发量减少67.96%;各处理高温期均≥3 d,发芽指数≥80%,表明堆体已经腐熟,无植物毒性。综上,番茄茎秆好氧堆肥中添加氯化钙,对于减少堆肥过程中的氮素损失较为理想。本研究可为番茄茎秆好氧堆肥保氮工艺优化提供理论依据。 相似文献
39.
土壤及泥沙颗粒组成与养分流失的研究 总被引:6,自引:6,他引:6
利用自然降雨影响下的农田为试验样地,分析了降雨前后土壤颗粒组成与养分含量的变化,探讨了流失泥沙颗粒组成与养分的变化特征。结果表明,在降雨后,西瓜地与油菜地表土颗粒组成呈现粘粒与粉粒含量减少,砂粒含量相对增加的趋势;土壤养分含量都有不同程度的下降,其中水解氮与速效磷下降的幅度很大,西瓜地与油菜地水解氮降雨后降幅分别为9.67%和7.99%,速效磷的降幅分别为9.20%和8.76%;全氮养分降幅很小,西瓜地与油菜地分别为2.17%和1.54%;流失泥沙细小颗粒含量与养分含量随时间基本都呈降低的变化趋势,并且细小颗粒含量与携带流失的养分含量有显著甚至极显著的正相关性;流失泥沙具有富集粘粒和富集养分的特性,油菜地与西瓜地粘粒富集率分别为1.23和1.20,两样地全氮与速效磷的富集率都在1.3以上,而全磷和水解氮富集率基本处在1.1-1.3之间。 相似文献
40.
华西雨屏区5种坡地利用方式产流产沙与养分流失特征 总被引:2,自引:0,他引:2
选择5种坡地利用方式,分别是裸地、农耕地(玉米)、荒草地、巨桉林地Ⅰ与巨桉林地Ⅱ,建立人工径流小区,对2006年6~11月各小区产流产沙及养分流失进行对比研究.结果表明:(1)5种坡地利用方式产流产沙差异显著(P<0.05),径流深依次是裸地(250.9 mm)>农耕地(232.9 mm)>荒草地(175.4 mm)>巨桉林地Ⅰ(170.5 mm)>巨桉林地Ⅱ(141.3 mm);产沙量大小依次为:农耕地(313.63 t/km2)>裸地(176.80 t/km2)>荒草地(94.45 t/km2)>巨桉林地Ⅰ(90.58 t/km2)>巨桉林地Ⅱ(36.37 t/km2).(2)5种坡地利用方式养分流失差异显著(P<0.05),其流失量大小顺序均为钾素>磷素>氮素.其中,氮素与磷素流失以水溶态为主,平均为96.16%与69.45%;钾素以颗粒态(与泥沙结合态)为主,平均为74.93%.(3)不同坡地产流产沙主要影响因素不同,裸地与农耕地受降雨影响较大,而荒草地与巨桉林地受人为干扰因素较大.(4)调整农事活动、改善经营措施与减少人为干扰对防止坡地产流产沙以及养分流失具有重要作用. 相似文献