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1.
本试验在四只装有永久性瘤胃瘘管的徐淮山羊身上采集瘤胃液,进行体外培养研究不同粗精比底物(10∶0、8∶2、6∶4、4∶6)对培养液pH值和VFA的影响,结果表明,添加一定精料可以提高微生物的发酵水平,且当粗精比水平为8∶2与6∶4时,瘤胃发酵水平高于其它各试验组,对照组在整个培养阶段均处于最低水平。  相似文献   

2.
试验选用4头带有瘤胃瘘管的内蒙古白绒山羊作为瘤胃液供体羊,以2种不同精粗比(2:8和3:7)的粗料型日粮为培养底物,研究不同苹果酸添加量(0、3、6、9和12 mmol/L)对内蒙古白绒山羊瘤胃发酵的影响.结果表明,不同精粗比日粮下,产气量、氨氮浓度、TVFA浓度及干物质(DM)降解率均是3:7日粮的较高,而pH以2:8日粮略高,差异均不显著.添加苹果酸后,3:7日粮在培养2和18h后,各试验组产气量、TVFA浓度、DM降解率均比对照组高,差异显著;而氨氮浓度是6和9mmol/,L组均显著高于对照组;2:8日粮在培养24 h后,各试验组的产气量、TVFA浓度、DM降解率和氨氮浓度均高于对照组,但差异不显著;pH在2种日粮下均降低,培养2和4 h,差异显著,但最终pH都超过6.30,适合正常瘤胃内环境的pH.  相似文献   

3.
试验旨在研究不同精粗比及VA水平对体外瘤胃发酵参数的影响。以3头体重相近,装有永久性瘤胃瘘管的荷斯坦奶牛为试验动物,采用2×3完全随机试验设计,第一因素为培养底物的精粗比,设2∶8和5∶5两个水平,第二因素为VA的添加剂量,设3个水平,分别为每毫升培养液中5.8、11.7和23.3IU。试验共分6个处理组,每处理组均进行4、8、12及24h4个时间点的体外批次培养,每个时间点3个重复。结果表明,VA添加水平在5.8~23.3IU/mL范围内,对奶牛瘤胃体外发酵的影响较小。高精料组的体外培养液中TVFA、乙酸、丙酸、丁酸含量均高于低精料组。体外培养24h时,高精料组乙酸/丙酸均显著低于低精料组(P〈0.05)。高精料组的pH值均显著低于低精料组(P〈0.05);氨氮浓度与BCP含量均显著高于低精料组(P〈0.05)。  相似文献   

4.
日粮精粗比与VA添加水平对奶牛体外瘤胃发酵参数的影响   总被引:1,自引:0,他引:1  
试验旨在研究不同精粗比及VA水平对体外瘤胃发酵参数的影响。以3头体重相近,装有永久性瘤胃瘘管的荷斯坦奶牛为试验动物,采用2×3完全随机试验设计,第一因素为培养底物的精粗比,设2∶8和5∶5两个水平,第二因素为VA的添加剂量,设3个水平,分别为每毫升培养液中5.8、11.7和23.3IU。试验共分6个处理组,每处理组均进行4、8、12及24h4个时间点的体外批次培养,每个时间点3个重复。结果表明,VA添加水平在5.8~23.3IU/mL范围内,对奶牛瘤胃体外发酵的影响较小。高精料组的体外培养液中TVFA、乙酸、丙酸、丁酸含量均高于低精料组。体外培养24h时,高精料组乙酸/丙酸均显著低于低精料组(P<0.05)。高精料组的pH值均显著低于低精料组(P<0.05);氨氮浓度与BCP含量均显著高于低精料组(P<0.05)。  相似文献   

5.
试验旨在研究不同精粗比及VA水平对体外瘤胃发酵参数的影响.以3头体重相近,装有永久性瘤胃瘘管的荷斯坦奶牛为试验动物,采用2×3完全随机试验设计,第一因素为培养底物的精粗比,设2∶8和5∶5两个水平,第二因素为VA的添加剂量,设3个水平,分别为每毫升培养液中5.8、11.7和23.3 IU.试验共分6个处理组,每处理组均进行4、8、12及24h4个时间点的体外批次培养,每个时间点3个重复.结果表明,VA添加水平在5.8~23.3 IU/mL范围内,对奶牛瘤胃体外发酵的影响较小.高精料组的体外培养液中TVFA、乙酸、丙酸、丁酸含量均高于低精料组.体外培养24h时,高精料组乙酸/丙酸均显著低于低精料组(P<0.05).高精料组的pH值均显著低于低精料组(P<0.05);氨氮浓度与BCP含量均显著高于低精料组(P<0.05).  相似文献   

6.
研究旨在评价表面活性剂吐温对不同精粗比发酵底物体外发酵特性的影响.采用体外培养技术,以不同精粗比的混合饲料(15 85、30 70、45 55)为发酵底物,在稀释混合绵羊瘤胃液中分别添加0.2%的吐温20、吐温40、吐温60或吐温80,厌氧培养至9 h结束.结果表明:与对照组pH值相比,吐温80有降低的趋势,其它各组均差异不显著.与对照组相比,吐温40最高可提高还原糖浓度为45.68%(P<0.05,精粗比1中的6 h),吐温60最高可提高25.65%(P<0.05,精粗比2中的3 h),吐温80最高可提高28.70%(精粗比1中的6 h),而吐温20对各时间点还原糖浓度均无显著影响;吐温20最高可提高氨态氮浓度为16.05%(P<0.05,精粗比1中的6 h),吐温40最高可提高8.15%(精粗比3中的9 h),吐温60最高可提高7.02%(精粗比1中的3 h),吐温80最高可提高11.20%(P<0.05,精粗比1中的3 h ).不同类型的吐温均对微生物蛋白水平无显著影响.由此可见,在体外培养条件下,4种吐温对体外瘤胃发酵均具有一定的调节作用.  相似文献   

7.
本试验通过体外培养法,研究在不同精粗比日粮中添加α-亚麻酸,对延边黄牛体外瘤胃发酵模式及α-亚麻酸(ALA)氢化过程的影响。试验设5个底物精粗比,即精料∶粗料分别为2∶8、4∶6、5∶5、6∶4和8∶2,各组均添加3.0%的α-亚麻酸,每组3个重复。体外培养12 h,取3、6、9、12 h时间点培养液测定体外瘤胃发酵参数和脂肪酸含量。结果显示:在各时间点,随着精料比例的增加,pH值呈上升趋势,且8∶2组与其他4组比,分别高(3 h)3%、4%、4%、3%,(6 h)9%、6%、4%、3%,(12 h)5%、4%、3%、2%(P0.05)。添加α-亚麻酸条件下,不同粗精比对总挥发性脂肪酸(TUFA)无显著影响。6 h和12 h,乙酸浓度与精料添加比例呈反比。6∶4组丙酸浓度分别比其他4组高(6 h)29%、24%、19%、15%,(12 h)19%、17%、4%、4%(P0.01)。8∶2组NH_3-N浓度在各时间点分别比4∶6组高43%、30%、37%(P0.01)。随精料比例升高,各时间点的CH_4、CO_2和产气量均呈上升趋势,CH_4产量一直低于CO_2的产量。t11-C_(18)∶1浓度在整个培养时间内随粗料比例的下降而减少,在6 h时2∶8组比8∶2组高64%(P0.01)。6 h、12 h,各组共轭亚油酸(CLA)浓度无显著差异。各时间点,c9,c12-C_(18)∶2浓度随粗料添加量下降而减少,在6 h、12 h,2∶8组比8∶2组分别高81%、93%(P0.01);总Cln A的变化趋势与之相同,各时间点2∶8组比8∶2组分别高32%(P0.05)、87%(P0.01)、119%(P0.01)。由此可见,不同精粗比日粮和α-亚麻酸影响体外瘤胃发酵参数,高精料日粮可以提高总产气量和CO_2产量,同时抑制CH_4的生成。高精料日粮通过降低TVFA含量增加瘤胃pH值。试验中添加α-亚麻酸,促进了氢化微生物对亚麻酸的氢化作用,同时抑制了亚油酸的氢化过程。  相似文献   

8.
瘤胃是反刍动物营养物质利用的第一关,饲料中60%的有机物质在瘤胃内消化,50%左右的纤维物质和88%的淀粉也在这里消化,因此,瘤胃在反刍动物代谢方面起着举足轻重的作用.瘤胃发酵主要受瘤胃微生物区系的影响,而瘤胃微生物区系的变化与瘤胃内环境密切相关.饲料组成包括日粮精粗比等是调控瘤胃内环境的主要因素.因此,此次试验是在精粗比分别为3:7和2:8的2种日粮条件下,对绒山羊瘤胃内环境和发酵指标进行了测定,目的是为绒山羊的生产实践和实施营养调控技术提供理论依据.  相似文献   

9.
瘤胃发酵调控研究进展   总被引:7,自引:0,他引:7  
本文综述了通过调控饲料的加工细度和饲料精粗比 ,去瘤胃原虫或向日粮中添加唾液盐、应用酵母培养物及瘤胃素调控瘤胃发酵来提高饲料利用率的方法。并讨论了调控效果及调控瘤胃发酵应该注意的一些问题  相似文献   

10.
本试验旨在研究不同精粗比饲粮中添加甘露寡糖(MOS)对绵羊体外瘤胃发酵的影响。采用4×6二因子析因试验设计,在4种不同精粗比(20∶80、30∶70、40∶60、50∶50)饲粮中分别添加6个水平(0、0.4%、0.8%、1.2%、1.6%、2.0%)的MOS,制备出24种底物,以体外产气法对各底物培养3、6、9、12和24 h,对体外培养液p H、氨态氮(NH_3-N)浓度和挥发性脂肪酸(VFA)浓度进行测定。结果表明:精粗比对培养液p H、NH_3-N浓度、总挥发性脂肪酸(TVFA)浓度和丁酸含量产生了显著影响(P0.05),MOS水平对培养液NH_3-N浓度产生了显著影响(P0.05),精粗比与MOS水平对培养液NH_3-N浓度产生显著的交互作用(P0.05)。随着精粗比的提高,培养液TVFA浓度和丁酸含量升高,而p H和NH_3-N浓度降低;随着MOS水平升高,培养液NH_3-N浓度略有升高。综合得出,不同精粗比饲粮中添加MOS对绵羊体外瘤胃发酵NH_3-N浓度有显著影响,其中MOS的影响较轻微,尚未呈现剂量效应,主体起作用的仍是精粗比;饲粮精粗比的提高增加了绵羊体外瘤胃发酵VFA浓度,降低了p H和NH_3-N浓度。  相似文献   

11.
Heartworm in dogs in Canada in 1984   总被引:4,自引:4,他引:0       下载免费PDF全文
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.

  相似文献   

12.
13.
Heartworm in dogs in Canada in 1983   总被引:6,自引:6,他引:0       下载免费PDF全文
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.

  相似文献   

14.
15.
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.  相似文献   

16.
Heartworm in dogs in Canada in 1985   总被引:3,自引:3,他引:0       下载免费PDF全文
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.

  相似文献   

17.
Heartworm in dogs in Canada in 1988   总被引:1,自引:1,他引:0       下载免费PDF全文
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%).  相似文献   

18.
Heartworm in dogs in Canada in 1989   总被引:1,自引:1,他引:0       下载免费PDF全文
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.

  相似文献   

19.
Heartworm in dogs in Canada in 1987   总被引:1,自引:1,他引:0       下载免费PDF全文
In late November 1987, 1246 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 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).  相似文献   

20.
Heartworm in dogs in Canada in 1986   总被引:2,自引:2,他引:0       下载免费PDF全文
In late December 1986, 1224 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 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, 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 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

  相似文献   

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