饲喂不同量的乳化棕榈油对奶牛BUN和MUN含量的影响

MUN的准确测定对于评价奶牛营养状况、降低饲料成本、提高产奶水平和改善乳品品质以及提高繁殖率均有重要意义。试验将60头日本荷斯坦奶牛(2、3胎次各30头)随机分为对照组和试验Ⅰ～Ⅴ组,每组10头(2、3胎次各5头),对照组饲喂TMR,试验Ⅰ～Ⅴ组饲喂TMR添加100.0、150.0、200.0、250.0、300.0g/(d·头)乳化棕榈油日粮,测定BUN和MUN及产奶性能。结果表明:①各试验组奶牛的BUN、MUN、乳蛋白和乳糖与对照组没有显著区别;②试验组日粮中增加250g/(d·头)乳化棕榈油时显著提高奶牛的产奶量、乳干物质和乳脂率;③MUN和BUN有高度相关性(r=0.8920,P<0.01)。     

脂肪酸添加剂抑制奶牛对环境污染的效果分析

将21头荷斯坦奶牛随机分为对照组和试验I～Ⅵ组,每组3头,对照组饲喂TMR,试验I～Ⅵ组饲喂TMR加50.0克、100.0克、150.0克、200.0克、250.0克、300.0克/头/天复合脂肪酸日粮。主要探讨复合脂肪     

脂肪酸添加剂抑制奶牛对环境污染的效果分析

将21头荷斯坦奶牛随机分为对照组和试验Ⅰ～Ⅵ组,每组3头,对照组饲喂TMR,试验Ⅰ～Ⅵ组饲喂TMR加50.0g、100.0g、150.0g、200.0g、250.0g、300.0g/头/d复合脂肪酸日粮.主要探讨复合脂肪酸对奶牛粪尿、N、P的排泄量和CH4释放量的影响.结果表明,TMR加150.0g/头/日～300.0g/头/d复合脂肪酸,比对照组CH4释放量减少11.40%～18.38%(P<0.01),粪尿和N及总P的排泄量分别降低1.38%～5.32%(P>0.05),11.84%～26.68%(P<0.01)和2.32%～4.86%(P>0.05),乳脂率提高10.76%～14.17%(P<0.05),有效抑制奶牛对周围土壤水源和空气的污染,显著提高奶牛的生态效益和经济效益.     

添加膨化全脂大豆对高产奶牛血液和乳中尿素氮的影响

选择12头基本条件相近、泌乳50d左右的中国荷斯坦高产奶牛,随机分为四组,采用4×4复合拉丁方试验设计研究高产奶牛日粮中添加膨化全脂大豆对血中尿素氮(BUN)与乳中尿素氮(MUN)动态关系的影响。在基础日粮(TMR)中加入不同水平(0kg、1kg、1.7kg、2.5kg)膨化全脂大豆,每期试验21d,共四期。每期试验第15d、17d、19d、21d取奶样,试验第21d取血样。试验结果表明,对乳中尿素氮,1kg组与对照组差异不显著(P>0.05),1.7kg添加水平与对照组的差异极显著(P<0.01),2.5kg组与对照组的差异显著(P<0.05);对于血液尿素氮2.5kg添加水平显著高于其他三个组(P<0.05)。经BUN与MUN相关分析,MUN值约为BUN的80%。     

日粮瘤胃能氮平衡对奶牛生产性能和牛奶中尿素氮的影响

本研究以12头泌乳中期荷斯坦牛为研究对象,采用随机区组设计分为3组,在干物质进食量相似的条件下,增加瘤胃快速可发酵能量,用玉米粉颗粒替代甜菜渣颗粒,三个处理分别替换0kg、0．4kg和0．8kg,试验期61d。结果表明,日粮处理对奶牛的产奶量和乳成分没有明显影响,玉米粉颗粒替代甜菜渣颗粒饲喂奶牛后可显著降低牛奶中尿素氮（MUN）浓度,评价目粮的瘤胃能氮平衡表明为正平衡,有明显低水平的MUN。试验证明,可以用日粮瘤胃能氮平衡判断饲喂日粮对奶牛MUN的影响。     

脂肪酸添加剂对奶牛瘤胃挥发性脂肪酸和甲烷的影响

21头安装瘤胃瘘管的荷斯坦产奶牛随机分为对照组和试验Ⅰ~Ⅵ组,每组3头,对照组饲喂全混日粮(TMR),试验Ⅰ~Ⅵ组每天饲喂TMR加50.0 g、100.0 g、150.0 g、200.0 g、250.0 g、300.0 g/头复合脂肪酸日粮,主要探讨复合脂肪酸对奶牛瘤胃甲烷(CH4)产量、挥发性脂肪酸(VFA)、氨氮(NH3-N)浓度和pH值及产奶性能的影响。结果,TMR中每天添加150.0~200.0 g/头复合脂肪酸,明显(P<0.05)提高奶牛乳脂率和瘤胃乙酸浓度,显著(P<0.05)降低奶牛的CH4释放量、CH4能/GE值和瘤胃NH3-N浓度,对奶牛的标准乳(FCM)、乳干物质、乳蛋白和乳糖均有提高趋势,能有效地提高奶牛的经济效益和生态效益。     

脂肪酸添加剂抑制奶牛对环境污染的效果分析

将21头荷斯坦奶牛随机分为对照组和试验Ⅰ~Ⅵ组,每组3头,对照组饲喂TMR,试验Ⅰ~Ⅵ组饲喂TMR加50.0g、100.0g、150.0g、200.0g、250.0g、300.0g/头/d复合脂肪酸日粮。主要探讨复合脂肪酸对奶牛粪尿、N、P的排泄量和CH4释放量的影响。结果表明,TMR加150.0g/头/日~300.0g/头/d复合脂肪酸,比对照组CH4释放量减少11.40%~18.38%(P<0.01),粪尿和N及总P的排泄量分别降低1.38%~5.32%(P>0.05),11.84%~26.68%(P<0.01)和2.32%~4.86%(P>0.05),乳脂率提高10.76%~14.17%(P<0.05),有效抑制奶牛对周围土壤水源和空气的污染,显著提高奶牛的生态效益和经济效益。     

人工TMR饲喂奶牛的效果

选用60头处于泌乳中期的荷斯坦奶牛,根据胎次和产奶量分为2组进行饲养试验,对照组和试验组各30头。对照组采用传统粗精料分开的饲喂方式,试验组优化原有饲料配方后,采用人工TMR的饲喂方式。试验结果表明,试验组比对照组提高产奶量4.75%,每头奶牛每天利润增加1.46元。     

奶牛饲喂不同精粗料比TMR对排泄粪尿和氮磷的影响

将18头荷斯坦产奶牛随机分为试验6组,每组3头,试验Ⅰ～Ⅵ组奶牛依次饲喂不同精粗料比(精料:粗料)的TMR1 (20∶80)、TMR2(30∶70)、TMR3 (40∶60)、TMR4 (50∶50)、TMR5 (60∶40)、TMR6 (70∶30)的日粮,探讨不同精粗料比TMR对奶牛粪尿、N、P的排泄量和CH4释放...     

TMR日粮不同苜蓿干草长度对奶牛生产性能的影响

探讨TMR日粮中不同长度的苜蓿干草对奶牛产奶量及其乳成分的影响。本试验选用产奶量、泌乳天数、膘情和胎次相近的健康荷斯坦泌乳奶牛40头,随机分为两组,即试验1组20头,饲喂苜蓿干草长度为2.52cm的TMR日粮,试验2组20头,饲喂苜蓿干草长度为6.46cm的TMR日粮。试验分两期完成,Ⅰ期日粮鲜重的精粗比例为20：80,Ⅱ期日粮鲜重的精粗比例为30：70。采用双因子重复方差试验设计。结果表明：在Ⅰ期和Ⅱ期两期试验中,不同长度苜蓿干草TMR日粮对奶牛的产奶量均无显著影响（P〉0.05）,但对奶牛的干物质采食量有显著影响（P〈0.05）,试验1组比试验2组奶牛的干物质采食量在Ⅰ期和Ⅱ期试验中分别显著地提高了18.36%、7.40%。在Ⅰ期试验中,试验2组乳蛋白极显著高于试验1组（P〈0.01）,较试验1组提高了11.82%;在Ⅱ期试验中,试验1组乳脂率显著高于试验2组（P〈0.05）,较试验2组提高了8.89%。     

Scrapie in goats in Cyprus

Ovine scrapie was first recorded in Cyprus in 1985. Subsequently four dairy goats kept in two mixed flocks with affected sheep developed characteristic clinical signs similar to those seen in sheep. Fifteen goats from the two flocks were examined histologically and neurological lesions consistent with a diagnosis of scrapie were found in the four animals and in three others which had subsequently developed early neurological signs. These lesions were similar to those of naturally-affected sheep although neuronal degeneration and vacuolation were more severe in some cases.     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.

     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1988

In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.