维生素B_2对笼养蛋雏鸭生长性能的影响

试验旨在研究饲粮添加不同水平的维生素B(2VB2)对笼养蛋雏鸭(1～28日龄)生长性能的影响。选用1日龄平均体重相近[(43.13±1.19)g]的金定蛋雏鸭288只,采用单因素随机分组试验设计。共分为6组,每组6个重复,试验期4周,饲粮中添加VB2水平分别为0、4、6、10、20、50mg/kg。试验结果显示:①在试验全期添加VB2水平第10、20mg/kg组的日增重显著高于不添加VB2处理组(第Ⅰ组)(P<0.05),②试验期内每一周各处理组蛋雏鸭的采食量差异不显著(P>0.05),③在试验第1、4周和全期添加VB2的第Ⅳ组的料重比显著低于不添加VB2的第Ⅰ组(P<0.05)。全期平均料重比最低的是添加VB2水平为10mg/kg组。故试验研究认为,为了降低饲料成本,保证饲料安全,饲粮中添加10mg/kgVB2能显著增强蛋雏鸭的生长性能。     

低温与维生素E对笼养蛋雏鸭生长性能、抗氧化能力及血糖血脂的影响

本试验旨在研究适温、低温的环境中日粮添加不同水平(20、220和420IU/kg)的维生素E(VE)对蛋雏鸭生长性能、抗氧化能力及血液中血糖血脂浓度的影响。以1日龄蛋雏鸭为试验动物,采用2×3(温度×VE)重复试验设计。结果表明,低温显著降低雏鸭生长性能,提高采食量(P<0.01)和料重比(P<0.01),降低日增重(P<0.01)。与添加20IU/kg处理组相比,添加220和420IU/kg的VE对提高全期平均日增重和改善饲料转化率有显著作用(P<0.01)。温度对血清中总抗氧化能力(T-AOC),丙二醛(MDA)水平无显著影响,而添加220和420IU/kg的VE会使雏鸭血清中总抗氧化能力T-AOC显著升高(P<0.05),丙二醛MDA水平降低。温度对甘油三酯,葡萄糖的影响极显著(P<0.01),甘油三酯、葡萄糖浓度均随温度降低而升高(P<0.01),而随添加VE浓度升高均有降低的趋势(P>0.05)。因此,日粮中添加220和420IU/kg的VE能显著改善生长性能,提高机体抗氧化能力,在一定程度上调节机体血糖血脂代谢。VE添加水平为220IU/kg时在正常育雏温度和低于正常育雏温度(5±1)℃下的生长性能和抗氧化能力均较好。     

饲粮锌水平对笼养蛋雏鸭生长性能、抗氧化功能及免疫器官发育的影响

本试验旨在研究饲粮锌水平对笼养蛋雏鸭生长性能、抗氧化功能及免疫器官发育的影响.试验采用单因素完全随机分组设计,选择健康1日龄金定蛋雏鸭180只,随机分成5组,每组6个重复,每个重复6只鸭.对照组(Ⅰ组)饲喂基础饲粮,试验组(Ⅱ～Ⅴ组)分别饲喂在玉米-豆粕型基础饲粮中添加20、40、60、80 mg/kg锌(ZnSO4·7H2O)的试验饲粮.试验期4周.结果表明:1)Ⅲ、Ⅳ组蛋雏鸭的料重比和Ⅲ组的平均日增重显著高于对照组(P＜0.05),雏鸭平均日增重、料重比随饲粮锌水平的增加呈明显的二次曲线变化,以此为指标估测的锌适宜添加水平分别是50.4和54.7 mg/kg;2)Ⅲ组血清和肝脏总抗氧化能力(T-AOC)、血清铜锌超氧化物歧化酶( CuZn-SOD)活性、肝脏丙二醛(MDA)含量、肝脏谷胱甘肽过氧化物酶(GSH-Px)活性与对照组相比差异显著(P＜0.05),估测的锌适宜添加水平分别是44.6、47.8、55.7、43.4、54.2 mg/kg,而血清MDA含量、血清GSH-Px活性和肝脏CuZn-SOD活性与对照组差异不显著(P＞0.05);3)Ⅲ组胸腺指数、脾脏指数、法氏囊指数均显著高于对照组(P＜0.05).由此可见,蛋雏鸭采食玉米-豆粕型基础饲粮(含锌33.3 mg/kg)时,锌的适宜添加水平为55.7 mg/kg.     

微量元素硒对笼养蛋雏鸭生长性能、免疫器官发育及抗氧化功能的影响

试验旨在研究饲粮中微量元素硒添加水平对笼养蛋雏鸭生长性能、免疫器官发育及抗氧化功能等方面的影响。试验采用单因素完全随机分组设计,选取1日龄健康金定蛋雏鸭180只,随机分为5组,每组6个重复,每个重复6只雏鸭。第Ⅰ组为对照组,饲喂玉米-豆粕型基础日粮(硒含量为0.042 mg/kg),第Ⅱ~Ⅴ组分别饲喂在基础日粮中添加0.1、0.15、0.2、0.3 mg/kg硒(实际添加物为亚硒酸钠)的试验日粮,试验期4周。结果表明:①第Ⅲ组的平均日增重、料重比与对照组相比均差异极显著(P<0.01),且日增重和料重比随饲粮硒含量的增加呈明显的二次曲线变化;②饲粮中添加硒可促进免疫器官发育,但对胸腺指数以外的免疫器官指数影响不显著(P>0.05);③饲粮中添加硒可极显著提高笼养蛋雏鸭GSH-Px活性和T-AOC(P<0.01),降低血清和肝脏MDA含量(P<0.01);④以试验各项测定结果为依据,估测的硒适宜添加水平分别是0.154、0.172、0.180 mg/kg。采用玉米-豆粕型基础日粮蛋雏鸭添加量为0.180 mg/kg时效果最好。     

维生素C对笼养蛋雏鸭的生产性能和机体抗氧化能力的影响

本文旨在研究玉米-豆粕型日粮添加不同水平维生素C(VC)对笼养蛋鸭育雏期(1～28日龄)的生产性能和抗氧化能力的影响.试验采用单因素随机分组设计的方法,选用1日龄平均体重相近的金定蛋雏鸭288只,随机分为6组(各处理日粮中分别添加VC 0、150、300、400、800、1 400 mg/kg),每组6个重复,每个重复8只鸭,结果表明:①在笼养蛋鸭育雏期添加150～1 400 mg/kg VC能显著提高日增重、饲料效率和抗氧化能力,显著降低丙二醛(MDA)的浓度(P<0.05).②5日龄,日粮添加800 mg/kg VC时血清和肝脏中超氧化物岐化酶(SOD)、过氧化氢酶(CAT),总抗氧化能力(T-AOC)的活性最高;28日龄,日粮添加300～400 mg/kg VC时血清和肝脏中SOD、CAT和T-AOC活力较高;28日龄血清和肝脏抗氧化指标高于5日龄.③大剂量的VC对蛋鸭的生产性能和机体的抗氧化指标都有降低的趋势.因此在本试验条件下得出:笼养蛋雏鸭日粮中适当添加VC可提高生产性能和机体抗氧化能力,1～5日龄日粮添加VC 800 mg/kg,6～28日龄添加VC 300～400 mg/kg为适宜.     

饲粮维生素D添加水平对蛋雏鸭免疫及抗氧化功能的影响

本试验旨在研究饲粮维生素D添加水平对1～28日龄蛋雏鸭免疫及抗氧化功能的影响,以探讨饲粮维生素D的适宜添加量。试验选取健康、体重相近的1日龄金定蛋雏鸭180只,随机分为5组(Ⅰ～Ⅴ组),每组6个重复,每个重复6只试鸭。采用玉米-豆粕型基础饲粮,Ⅰ组(对照组)试鸭饲喂基础饲粮,Ⅱ～Ⅴ组试鸭分别饲喂在基础饲粮中添加110、220、550、1 000 IU/kg维生素D的试验饲粮,试验期4周。结果表明:饲粮添加550 IU/kg维生素D可显著提高胸腺指数、脾脏指数(P<0.05),并显著增强肝脏超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05),降低血清白细胞介素-2(IL-2)及血清和肝脏丙二醛(MDA)含量(P<0.05);饲粮添加220、550 IU/kg维生素D可显著提高血清总蛋白(TP)和白蛋白(ALB)含量(P<0.05),并显著增强血清SOD和GSH-Px活性及血清和肝脏总抗氧化能力(T-AOC)(P<0.05)。综合本试验结果,在玉米-豆粕型基础饲粮中添加适量的维生素D可提高1～28日龄蛋雏鸭的免疫及抗氧化功能。综合考虑各指标,通过二次回归模型估测得出维生素D适宜添加量为512.8～550.0 IU/kg。     

精氨酸对笼养育雏期蛋鸭生产性能及抗氧化功能的影响

试验旨在研究饲粮中添加不同水平精氨酸对0~4周龄笼养蛋雏鸭生长性能及抗氧化功能的影响,探讨笼养育雏期蛋鸭适宜的精氨酸添加水平。试验采用单因素完全随机分组设计,选择健康1日龄金定蛋雏鸭180只,随机分为5组,每组6个重复,每个重复6只鸭,对照组饲喂基础日粮,试验组饲喂在玉米-豆粕型基础饲粮基础上分别添加0.10%、0.20%、0.30%、0.40%精氨酸的试验饲粮,试验期4周。结果表明：①饲粮中添加精氨酸平均日增重Ⅲ组显著高于其他各组(P<0.05),Ⅱ、Ⅳ、Ⅴ组间差异均不显著(P>0.05),Ⅱ、Ⅳ组显著高于Ⅰ组(P<0.05);平均日采食量以Ⅰ组最高,但各组间差异均不显著(P>0.05);料重比以Ⅲ组最低,显著低于其他各组(P<0.05),Ⅱ、Ⅳ、Ⅴ组间差异不显著(P>0.05),同时,Ⅱ、Ⅳ、Ⅴ组显著低于对照组(P<0.05)。②Ⅲ组血清和肝脏总抗氧化能力(T-AOC)与对照组相比差异显著（P<0.05),Ⅱ组血清谷胱甘肽过氧化物酶(GSH-Px)活性与对照组相比差异显著(P<0.05);Ⅳ组肝脏超氧化物歧化酶(SOD)活性与对照组相比差异显著(P<0.05);Ⅱ、Ⅲ、Ⅳ组肝脏丙二醛(MDA)含量与对照组相比差异显著(P<0.05),根据试验中有效评价精氨酸营养需要量的抗氧化指标,估测精氨酸添加水平分别为0.183%、0.198%、0.093%、0.208%。由此可见,蛋雏鸭采食玉米-豆粕型基础饲粮,精氨酸的适宜添加水平为0.093%~0.208%。     

维生素E对笼养蛋雏鸭免疫功能及血液中激素指标的影响

为研究不同水平的维生素E对笼养蛋雏鸭免疫功能及血液中激素指标的影响,将180只1日龄的健康金定蛋雏鸭随机分成5组,每组6个重复,每个重复6只鸭.第Ⅰ组为对照组,饲喂玉米-豆粕型基础饲粮(维生素E:15.4 IU/kg),第Ⅱ、Ⅲ、Ⅳ、Ⅴ组为试验组,在基础饲粮中分别添加10、15、20、40 IU/kg的维生素E.试验期为4周.结果表明:(1)维生素E对笼养蛋雏鸭T3、T4、生长激素(GH)影响显著(P＜0.05),但对血清皮质醇浓度影响不显著(P＞ 0.05);15 IU/kg维生素E添加组血清GH显著高于对照组(P＜0.05),15 IU/kg维生素E添加组血清T3、T4显著升高(P＜0.05);以T4、GH估测的维生素E适宜添加量为20.0～20.5 IU/kg.(2)IgA、IgM、IgG、白介素-2含量随着日粮维生素E水平升高有增加的趋势,其中15 IU/kg维生素E添加组IgA、IgM、白介素-2显著升高(P＜0.05).(3)饲粮中添加15 IU/kg的维生素E胸腺、法氏囊指数均比对照组显著提高(P＜0.05),但脾脏指数各组间差异不显著(P＞0.05);以IgA、IgM、白介素-2估测维生素E适宜添加量为18.7～20.5 IU/kg.综合考虑,蛋雏鸭饲粮中维生素E适宜添加量为18.7～20.5 IU/kg.     

饲粮中添加辣木梗粉对蛋雏鸭生长、免疫及抗氧化功能的影响

本试验通过在饲粮中添加不同水平的辣木梗粉,研究其对1～28日龄蛋雏鸭生长、免疫及抗氧化功能的影响,以探讨辣木梗粉的适宜添加量。试验选取健康、体重相近的1日龄三穗蛋雏鸭135只,随机分为3组(Ⅰ～Ⅲ组),每组3个重复,每个重复15只试鸭。采用基础饲粮加辣木梗粉进行饲喂,Ⅰ组(对照组)饲喂基础饲粮,Ⅱ、Ⅲ组在基础饲粮中添加20 g/kg和40 g/kg辣木梗粉,试验期4周。结果表明:20 g/kg辣木梗粉添加组的平均日采食量(ADFI)分别比空白对照组和40 g/kg辣木梗粉添加组显著提高8.6%和9.8%(P <0.05);20 g/kg和40 g/kg g辣木梗粉添加组的平均日增重(ADG)分别比空白对照组显著提高11.8%和18.3%(P <0.05);40 g/kg辣木梗粉添加组的料重比(F/G)分别比空白对照组和20 g/kg辣木梗粉添加组显著降低16.2%和14.1%(P <0.05);20 g/kg和40 g/kg辣木梗粉添加组血清白蛋白(ALB)含量比对照组分别显著提高39.1%和49.5%(P <0.05);20 g/kg辣木梗粉添加组的免疫蛋白M(IgM)含量比空白对照组显著提高了1.6%(P <0.05);20 g/kg辣木梗粉添加组的血清丙二醛(MDA)含量比空白对照组显著减少33.16%(P <0.05)。综上,在基础饲粮中添加适量的辣木梗粉可提高1～28日龄蛋雏鸭的免疫及抗氧化功能,对辣木梗粉在蛋雏鸭的应用上提供了参考依据。     

艾蒿水提物对肉仔鸡肝和胸肌抗氧化指标的影响

试验旨在研究不同水平的艾蒿水提物对肉仔鸡肝和胸肌抗氧化指标的影响。试验选取192只健康1日龄AA雏鸡,随机分为4个处理组,每组6个重复,每重复8只。4种饲粮分别在基础饲粮中添加0、500、1 000和2 000 mg/kg的艾蒿水提物。结果表明:21日龄雏鸡,1 000 mg/kg添加组的肝过氧化氢酶(CAT)活性极显著升高(P0.01);2 000 mg/kg添加组的肝CAT和谷胱甘肽过氧化物酶(GSH-Px)活性显著或极显著高于对照组(P0.05或P0.01);42日龄雏鸡,500 mg/kg添加组的肝超氧化物歧化酶(TSOD)活性及胸肌总抗氧化能力(T-AOC)水平和T-SOD活性均显著升高(P0.05),且肝的GSH-Px活性极显著升高(P0.01);1000 mg/kg添加组的胸肌T-SOD活性极显著升高(P0.01);2 000 mg/kg添加组的肝T-AOC水平和胸肌T-SOD的活性显著或极显著升高(P0.05或P0.01),但肝CAT和T-SOD活性及胸肌T-AOC水平均显著降低(P0.05)。此外,500和1 000 mg/kg添加组的丙二醛(MDA)含量均显著降低(P0.05)。结果提示,日粮中添加艾蒿水提物可提高肉仔鸡肝和胸肌的抗氧化能力。     

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 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 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 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.

     

Heartworm in dogs in Canada in 1987

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%).     

Heartworm in dogs in Canada in 1986

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.

     

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.