过氧化氢酶对生长前期乌苏里貉生长性能、消化代谢、血清生化和免疫指标的影响

试验旨在研究日粮中添加过氧化氢酶（catalase,CAT）对生长前期雄性乌苏里貉生长性能、营养物质消化率、氮代谢、血清生化和免疫指标的影响。随机选取（60±5）日龄健康、体重相近的雄性乌苏里貉60只,随机分为4组,每组15只貉,每个重复1只貉。分别饲喂含CAT 0(1组)、0.10%(2组)、0.15%(3组)、0.20%(4组)的试验饲粮,预试期7 d,正试期82 d。试验期间每组随机选取8只乌苏里貉采用全收粪法进行消化代谢试验。结果表明：(1)2组末重（FBW）、平均日增重（ADG）均显著高于1组（P<0.05）,料重比（F/G）显著低于1组（P<0.05）;(2)2组的粗蛋白（CP）消化率极显著高于1组（P<0.01）;2组的粗脂肪（EE）消化率极显著高于1组（P<0.05）,对干物质（DM）消化率、氮沉积没有显著影响（P>0.05）;(3)CAT组血清中尿素氮（urea nitrogen,UREA）的含量显著低于1组（P<0.05）;2、3组血清中碱性磷酸酶（alkaline phosphatase,ALP）含量极显著低于1组（P<0...     

甘露寡糖对冬毛期乌苏里貉生长性能、 血清免疫和抗氧化指标及脏器指数的影响

试验旨在研究不同添加水平的甘露寡糖对冬毛期乌苏里貉生长性能、血清免疫指标、血清抗氧化指标和脏器指数的影响。选取日龄[(120±5)d]接近、体重接近的健康雄性乌苏里貉24只,随机分为4组,每组6只貉,在基础日粮中分别添加0(对照组)、0.5 g/kg(I组)、1 g/kg(Ⅱ组)、2 g/kg(Ⅲ组)的甘露寡糖,试验期45 d。结果表明:(1)试验组乌苏里貉末重和平均日增重与对照组相比无显著差异(P>0.05)。(2)试验Ⅰ组和Ⅱ组粗蛋白消化率显著高于对照组(P<0.05)。(3)试验Ⅰ组和Ⅱ组血清中免疫球蛋白A(IgA)、免疫球蛋白G(IgG)含量显著高于对照组(P<0.05);试验组免疫球蛋白M(IgM)含量均显著高于对照组(P<0.05)。(4)试验Ⅰ组血清中过氧化氢酶(CAT)活性显著高于对照组(P<0.05);试验组血清中总超氧化物歧化酶(T-SOD)活性均显著高于对照组(P<0.05)。(5)试验Ⅲ组胸腺指数显著高于对照组(P<0.05)。综上所述,在饲粮中添加0.5 g/kg和1 g/kg的甘露寡糖可以显著提高冬毛期乌苏里貉的免疫...     

铜对育成期乌苏里貉生长性能、营养物质消化率的影响

本试验旨在研究日粮中添加铜对育成期雄性乌苏里貉生长性能、营养物质消化率、氮、铜代谢及血清生化指标的影响。随机选取（60±5）日龄健康的雄性乌苏里貉105只,体重2.83 kg±0.37 kg,随机分为7组,每组15只貉,1只为1个重复。分别饲喂含蛋氨酸铜为0（对照组）、20（Ⅰ组）、30（Ⅱ组）、40（Ⅲ组）、50（Ⅳ组）、60（Ⅴ组）和200 mg/kg（Ⅵ组）的试验日粮,预试期7 d,正试期55 d。试验期间,每组随机选取8只乌苏里貉采用全收粪尿法进行消化代谢试验。结果表明：Ⅲ、Ⅳ组的末重显著高于对照组（P<0.05）,其余各组与对照组相比体重差异不显著。Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ组平均日增重（ADG）均显著高于对照组（P<0.05）。Ⅴ组的脂肪消化率显著高于对照组和Ⅰ组（P<0.05）。对照组和Ⅵ组的铜消化率显著高于Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组（P<0.05）。Ⅳ组的氮沉积显著高于对照组和Ⅰ组（P<0.05）。各组间铜摄入量存在显著差异（P<0.05）,粪铜含量随着铜添加水平的升高而显著升高（P<0.05）。Ⅴ、Ⅵ组尿铜显著高于Ⅰ、Ⅱ、Ⅲ、Ⅳ和对照组（P<0.05）。各铜添加组与对照组铜沉积差异显著（P<0.05）。Ⅵ组血清低密度脂蛋白（LDL）含量显著高于对照组和Ⅰ组（P<0.05）。Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ组血清白蛋白（ALB）含量显著高于对照组（P<0.05）。Ⅳ组血清尿素含量显著低于对照组（P<0.05）。在本试验中,育成期乌苏里貉日粮中铜添加量在30~50 mg/kg时可获得较好的生长性能。考虑到铜排放量、饲养成本、环境污染等因素,推荐育成期乌苏里貉铜添加量为30 mg/kg。     

饲粮蛋白质水平和限饲对冬毛期水貂生产性能、消化代谢和血清生化指标的影响

本试验旨在研究饲粮蛋白质水平和限饲对冬毛期水貂生产性能、消化代谢和血清生化指标的影响。选择150日龄健康美国短毛黑公貂40只,随机分为4组,每组10个重复,每个重复1只。Ⅰ、Ⅱ、Ⅲ组水貂分别饲喂蛋白质水平为22%、32%、42%的试验饲粮,Ⅳ组为限饲组,饲喂蛋白质水平为32%的试验饲粮,饲喂量为Ⅱ组的50%。预试期7 d,正试期53 d。结果表明:饲粮蛋白质水平对水貂的165日龄体重、体长、鲜皮长、鲜皮重、针毛长度和绒毛长度均无显著影响(P>0.05),但均以Ⅱ组的值最高。Ⅱ组的180和195日龄体重显著高于Ⅲ组(P<0.05),针毛细度和绒毛细度极显著高于Ⅰ、Ⅲ组(P<0.01)。饲粮蛋白质水平对水貂的干物质采食量无显著影响(P>0.05)。Ⅱ组的干物质排出量显著低于Ⅰ组(P<0.05),干物质、粗脂肪和碳水化合物消化率则极显著高于Ⅰ组(P<0.01),与Ⅲ组无显著差异(P>0.05)。Ⅱ组的沉积氮、净蛋白质利用率和蛋白质生物学价值显著或极显著高于Ⅰ、Ⅲ组(P<0.05或P<0.01)。Ⅰ、Ⅱ和Ⅲ组的血清白蛋白和球蛋白含量无显著差异(P>0.05),但Ⅱ组的血清总蛋白含量显著高于Ⅲ组(P<0.05)。Ⅱ组的血清谷草转氨酶活性极显著高于Ⅰ、Ⅲ组(P<0.01),血清碱性磷酸酶活性则显著低于Ⅰ组(P<0.05)。与Ⅱ组相比,Ⅳ组的针毛细度、绒毛细度、干物质采食量、干物质排出量、干物质消化率、粗蛋白质消化率、粗脂肪消化率、碳水化合物消化率、食入氮、沉积氮、净蛋白质利用率、蛋白质生物学价值以及血清谷草转氨酶活性显著或极显著降低(P<0.05或P<0.01),而血清谷丙转氨酶活性显著升高(P<0.05)。由此得出,冬毛期水貂饲粮适宜的蛋白质水平为32%。50%限饲对冬毛期水貂的体长、鲜皮长、鲜皮重、针毛长度和绒毛长度无显著影响,但是对针毛细度、绒毛细度以及蛋白质、脂肪和碳水化合物的消化率有显著影响。因此,在不影响水貂营养物质消化代谢和生产性能的基础上,适宜的限饲水平还有待于进一步研究。     

日粮不同蛋白质水平对冬毛期貉生长性能、血液生化指标及毛皮性状的影响

文章旨在研究日粮不同蛋白质水平对冬毛期貉生产性能、血液生化指标和毛皮性状的影响。试验选取中国农业科学院特产研究所毛皮动物实验基地的雄性乌苏里貉45只,体重约为(6.00±0.09)kg,随机分为3组,每组15只,分别饲喂高、中、低(28.81%、24.15%、22.03%)三个蛋白水平的日粮。结果显示:3个蛋白质水平的日粮对日增重、日采食量及料重比等均无显著影响(P0.05);血清尿素氮浓度,低蛋白水平组显著低于高蛋白水平组(P0.05);白蛋白、总蛋白、血清尿素氮均以中蛋白水平组最高,随着蛋白水平的增加,各个指标有下降的趋势;针绒毛平齐度高蛋白水平组显著低于中、低蛋白水平组(P0.05),针毛、绒毛细度,低蛋白水平组显著低于中、高蛋白水平组(P0.05),活体长、干皮长、干皮重、针毛长度、绒毛长度等毛皮性状均差异不显著(P0.05)。以上结果表明,在不额外添加氨基酸的条件下,日粮蛋白质水平降到24.15%基本不影响冬毛期貉的生产性能及毛皮性状,但蛋白水平降到22.03%时,对毛皮性状有一定程度的影响。     

铜对育成期乌苏里貉生长性能、营养物质消化率的影响

本试验旨在研究日粮中添加铜对育成期雄性乌苏里貉生长性能、营养物质消化率、氮、铜代谢及血清生化指标的影响。随机选取(60±5)日龄健康的雄性乌苏里貉105只,体重2.83 kg±0.37 kg,随机分为7组,每组15只貉,1只为1个重复。分别饲喂含蛋氨酸铜为0(对照组)、20(Ⅰ组)、30(Ⅱ组)、40(Ⅲ组)、50(Ⅳ组)、60(Ⅴ组)和200 mg/kg(Ⅵ组)的试验日粮,预试期7 d,正试期55 d。试验期间,每组随机选取8只乌苏里貉采用全收粪尿法进行消化代谢试验。结果表明:Ⅲ、Ⅳ组的末重显著高于对照组(P0.05),其余各组与对照组相比体重差异不显著。Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ组平均日增重(ADG)均显著高于对照组(P0.05)。Ⅴ组的脂肪消化率显著高于对照组和Ⅰ组(P0.05)。对照组和Ⅵ组的铜消化率显著高于Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组(P0.05)。Ⅳ组的氮沉积显著高于对照组和Ⅰ组(P0.05)。各组间铜摄入量存在显著差异(P0.05),粪铜含量随着铜添加水平的升高而显著升高(P0.05)。Ⅴ、Ⅵ组尿铜显著高于Ⅰ、Ⅱ、Ⅲ、Ⅳ和对照组(P0.05)。各铜添加组与对照组铜沉积差异显著(P0.05)。Ⅵ组血清低密度脂蛋白(LDL)含量显著高于对照组和Ⅰ组(P0.05)。Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ组血清白蛋白(ALB)含量显著高于对照组(P0.05)。Ⅳ组血清尿素含量显著低于对照组(P0.05)。在本试验中,育成期乌苏里貉日粮中铜添加量在30～50 mg/kg时可获得较好的生长性能。考虑到铜排放量、饲养成本、环境污染等因素,推荐育成期乌苏里貉铜添加量为30 mg/kg。     

准备配种期雌性蓝狐对不同蛋白质水平日粮营养物质消化率及氮代谢的比较研究

试验旨在研究准备配种期母狐对不同蛋白质水平日粮的消化代谢规律。选择健康母狐180只,随机分成4组,每组45个重复,每个重复1只。各组母狐分别饲喂蛋白质水平为21.64%（Ⅰ组）、26.21%（Ⅱ组）、30.43%（Ⅲ组）和35.10%（Ⅳ组）的日粮。预试期7 d,正试期45 d。结果表明,蛋白质消化率、干物质排出量、粪氮代谢的影响差异不显著,Ⅲ组和Ⅳ组的干物质采食量显著或极显著高于Ⅰ组和Ⅱ组（P<0.05或P<0.01）,Ⅲ组的脂肪消化率显著或极显著高于Ⅰ、Ⅱ和Ⅳ组（P<0.05或P<0.01）,Ⅳ组氮沉积极显著低于Ⅰ、Ⅱ和Ⅲ组（P<0.01）。随着饲料蛋白质水平的增加,食入氮和尿氮随之提高（P<0.05或P<0.01）,净蛋白利用率、蛋白质生物学价值逐渐降低（P<0.05或P<0.01）。由此得知,当蛋白质水平为30.43%时,各种营养物质消化率最为理想,但21.64%的蛋白质水平足以满足准备配种期雌性蓝狐的蛋白质需要,且蛋白质的利用率达到最高。     

育成期雄性幼貉日粮适宜蛋白质和能量水平的研究

选用健康乌苏里幼公貉63只,随机分为7组(每组9只)。1～4组用以探讨适宜蛋白质水平,其蛋白质水平分别为31.54%、36.39%,40.37%和43.53%;5-7组用以探讨适宜能量水平,其能量水平分别为19589.78,21860.94和22600.04k J/kg。试验分育成前期和冬毛生长期两个阶段进行,饲喂同一营养水平的日粮。结果表明,育成前期饲喂蛋白质水平为36.39%的日粮,可获得理想的体重、体长及经济效益。 冬毛生长期,日粮蛋白质水平在31.54%～43.53%范围内,对幼貉的体重和体长无显著影响。育成期以饲喂能量水平为21860.94～22600.04 k J/kg的日粮为宜。育成前期适宜的蛋能比为16.1～16.6,冬毛生长期为14.0～14.4。     

4月龄～8月龄藏獒最适蛋白水平及能蛋比的研究

本试验选用健康4月龄藏獒32头,随机分成4个处理组,饲喂4种蛋白质水平不同的日粮,研究日粮蛋白质水平及能蛋比对断奶到4月龄藏獒生长发育、营养物质消化率以及血液指标的影响。结果表明：平均日采食量以高蛋白组最高,料重比以高蛋白组最低,平均日增重以高蛋白组最高;能量和蛋白水平对体重、体高、体长、胸围、耳长和尾长有显著影响（P〈0．05）;日粮蛋白质水平低时,干物质消化率高,能量水平相同时,可消化蛋白质和尿能随蛋白水平升高而升高;不同蛋白质水平及能蛋比对藏獒血清蛋白质、白蛋白、白球比和血清尿素氦含量有显著影响（P〈0．05）。综合以上研究结果,4月龄～8月龄藏獒适宜的代谢能水平为15．68MJ／kg,蛋白质水平为21．06％。     

甘草提取物对冬毛期乌苏里貉生长性能、营养物质消化代谢、血清生化指标、毛皮品质及脏器指数的影响

本试验旨在研究饲粮中添加不同水平甘草提取物对冬毛期乌苏里貉生长性能、营养物质消化代谢、血清生化指标、毛皮品质及脏器指数的影响。试验选取135日龄的体重相近、雄性乌苏里貉75只，随机分成5组，每组15个重复，每个重复1只貉。基础饲粮中分别添加0（Ⅰ组）、100（Ⅱ组）、200（Ⅲ组）、300（Ⅳ组）、400 mg/kg（Ⅴ组）甘草提取物。预试期5 d，正试期62 d。试验测定不同组乌苏里貉生长性能、消化代谢、氮代谢、血清生化指标、毛皮品质及脏器指数等的变化。结果表明：1）试验Ⅳ组貉末重、平均日增重显著高于试验Ⅰ组及Ⅱ组（P <0.05），试验Ⅳ组及Ⅴ组料重比显著低于试验Ⅰ组及Ⅱ组（P<0.05）。2）试验Ⅴ组的粗蛋白质表观消化率显著高于试验Ⅰ组（P<0.05），各组间其他营养物质消化代谢指标无显著差异（P>0.05）。3）试验Ⅳ组食入氮含量与试验Ⅲ组差异不显著（P>0.05），但其显著低于试验Ⅰ组、Ⅱ组和Ⅴ组（P<0.05），试验Ⅳ组及Ⅴ组的氮沉积显著高于试验Ⅰ组（P<0.05），其余组间无显著差异（P>0.05）。4）试验Ⅴ组血清白蛋白含...     

Comparative immunogenicity and efficacy studies with oral rabies virus vaccine SAD P5/88 in raccoon dogs and red foxes.

A comparative study of immunogenicity and efficacy of the oral rabies virus vaccine SAD P5/88 in raccoon dogs and foxes was conducted. The raccoon dogs received 10(6.9) (n = 6), 10(6.3) (n = 6) or 10(5.7) FFU SAD P5/88 (n = 5) by direct oral application, and subsequently all animals seroconverted. The foxes received 10(7.2) (n = 4), 10(6.2) (n = 4), 10(5.2) (n = 4) and 10(4.2) FFU SAD P5/88 (n = 5) by the same route. On days 106 and 196 post vaccination 10 raccoon dogs and 16 foxes were challenged with a relevant street virus, respectively. All 10 raccoon dogs vaccinated with 10(6.3) (n = 5) or 10(5.7) FFU SAD P5/88 (n = 5) survived the challenge, whereas all control animals (n = 5) died of rabies. Two foxes vaccinated with 10(4.2) FFU and one fox vaccinated with 10(5.2) FFU died of rabies on day 7, 17 and 12 post infection, respectively. Also all control foxes succumbed to rabies. Our findings demonstrate that SAD P5/88 is not only an effective vaccine for oral vaccination of foxes but also for that of raccoon dogs.     

Effect of Different Ratios of Food to Water of Dry Powder Feed on Growth Performance，Nutrient Digestibility and Nitrogen Metabolism of Growing Wusuli Raccoon Dogs

This experiment was aimed to explore the effect of different ratios of food to water of dry powder feed on growth performance,nutrient digestibility and nitrogen metabolism of growing Wusuli raccoon dogs.Thirty 11-week-old healthy Wusuli raccoon dogs with average body weight of （3.47±0.20） kg were randomly assigned into 3 groups.The Wusuli raccoon dogs were fed experimental diets with dry powder feed of ratio of food to water of 1∶2.5 （group Ⅰ）,1∶3.5（group Ⅱ）,1∶4.5 （group Ⅲ）,respectively.The pre-test period lasted for 7 days and the trial period lasted for 67 days.The results showed that the average daily feed intake of each week from 11,12 to 13 weeks in groupⅠ was significantly less than that in groups Ⅱ and Ⅲ （P＜0.05）,the average daily feed intake of each week from 14,15 to 20 weeks was no significant difference among all groups （P＞0.05）.The total intake in group Ⅰ was significantly less than that in group Ⅱ （P＜0.05）.The average daily gain of each week from 15 to 17 weeks in group Ⅲ was significantly higher than that in group Ⅰ （P＜0.05）,while the average daily gain,total weight and the rate of feed intake to body gain in other week-old were no significant differences among all groups （P＞0.05）.The protein digestibility,fat digestibility and dry matter digestibility were no significant differences among all groups （P＞0.05）.The amount of urine in group Ⅲ was extremely significantly higher than that in groups Ⅰ and Ⅱ （P＜0.01）.The nitrogen intake,fecal nitrogen,urine nitrogen,nitrogen deposition,net protein utilization and biological value of protein were no significant differences among all groups （P＞0.05）.In conclusion,the appropriate ratios of food to water of dry powder feed of growing Wusuli raccoon dogs was 1∶3.5 to 1∶4.5.     

Efficient distribution of oral vaccines examined by infrared triggered camera for advancing the control of raccoon dog rabies in South Korea

The field distribution of the oral rabies vaccine is effective in controlling the spread of rabies. The present study aimed to investigate efficient distribution locations based on the environment, contact rate, and consumption by target wildlife species in South Korea. The target species (Korean raccoon dogs, domestic dogs, and feral cats) accounted for 945 contacts (52.2%), in total 1,808 contacts. There were 863 (47.8%) contacts by non-target species. Raccoon dogs, a main reservoir of rabies in South Korea, had the highest contact rate (34.1%) among all species. The contact rate by target species was highest at riparian sites and bushy mountainous vegetation, where raccoon dogs are abundant. There was remarkable contact by raccoon dogs in mountainous areas below 150 m with bushy vegetation. Our results indicate that these locations are efficient areas for vaccine distribution, especially targeting the raccoon dog. Vaccines were continuously contacted with intervals ranging from one hour to one day. Vaccines at 94.4% of the distribution points were completely consumed within two weeks. The mean consumption rate was 95.2 ± 1.93% during the overall study period. These findings suggest that the oral rabies vaccine attracts wildlife including domestic dogs and feral cats. Our results suggest that low sections of mountainous areas with bushy vegetation and/or neighboring riparian areas are rich in target wildlife species (especially raccoon dogs) and are efficient locations for vaccine distribution to control rabies in South Korea.     

乌苏里貉生长发育规律研究及其生长曲线模型拟合

选取60只分窝乌苏里仔貉,按出生窝别、出生时间、性别、体重分为4组,生长期和冬毛期分别饲喂4种不同的试验E／粮,研究其生长发育规律,拟合其体重和体长生长模型。结果表明：乌苏里貉周平均日增重在8～12周龄和18～24周龄有2个高峰期（分别为40g／d和50g／d）,体长生长速度在9～14周龄和20～22周龄有2个高峰期（分别为0．3cm／d和0．2cm／d）;体重和体长适宜生长曲线方程分别为：Y=241．47＋42．242X＋19．041X^2-0．399X^3（R^2=0．994）,Y=9．517＋3．374X-0．067X^2（R^2=0．992）。     

An epidemic of sylvatic rabies in Finland--descriptive epidemiology and results of oral vaccination.

When rabies reappeared in Finland in April 1988, the country had been rabies free since 1959. Soon a picture of sylvatic rabies become evident, its main vector and victim being the raccoon dog (Nyctereutes procyonoides). Between 8 April 1988 and 16 February 1989, 66 virologically verified cases were recorded (48 raccoon dogs, 12 red foxes, 2 badgers, 2 cats, 1 dog and 1 dairy bull) in an area estimated at 1700 km2 in south-eastern Finland. The greatest distance between recorded cases was 67 km. A positive reaction with monoclonal antibody p-41 indicated that the virus was an arctic-type strain. A field trial on oral immunization of small predators was initiated in September 1988 using Tübingen fox baits according to the Bavarian model of bait distribution. Each bait contained 5*10(7) TCID50/ml modified live rabies virus (SAD-B19). The 6 months' surveillance indicate a seroconversion rate of 72% (N = 126) in the raccoon dog population, 67% (N = 56) in the red foxes and 13% (N = 16) in the badgers, when titers greater than or equal to 1.0 IU/ml are considered seropositive. In the whole follow-up period, no statistically significant difference could be detected between the raccoon dogs and red foxes in the rate of seroconversion or in the uptake of tetracycline from the baits. Notably high antibody levels were recorded in both raccoon dogs and red foxes within 4-5 months after vaccination. Of the seropositive animals, the proportion of animals with titers 3.0 IU/ml or greater was higher in raccoon dogs (73%) than in red foxes (51%) (x2 = 5.29, p less than 0.05). The trial shows that raccoon dogs can be immunized against rabies in the field with vaccine baits originally developed for controlling sylvatic rabies in foxes.     

免疫组化法检测犬瘟热病毒在貉组织内的分布

对79只确诊为犬瘟热的病貉进行CDV在组织内的定位。采用HE染色检测到包涵体出现在肺(57只貉)、脑(19只貉)、肾(58只貉)、胃(63只貉)、脾(61只貉)、淋巴结(63只貉)、扁桃体(79只貉)。采用免疫组化方法检测出上述器官之外在足垫上皮细胞(70只貉)、鼻黏膜(69只貉)、支气管(71只貉)也有强阳性表达。结果表明,采用免疫组化方法能更加准确的对CDV在犬瘟热病貉组织内分布的定位,CDV分布最广泛的器官是扁桃体。     

Reproduction of the raccoon dog (Nyctereutes procyonoides) after feeding or food deprivation in winter

The wild raccoon dog (Nyctereutes procyonoides, Canidae, Carnivora) goes through autumn fattening followed by winter sleep. Farmed raccoon dogs also exhibit autumn fattening but not winter sleep, as a result of daily feeding and lack of nests. We studied the effects of food deprivation and winter sleep or active winter feeding on the physiology and reproduction of farm-born raccoon dogs. Eighty-six animals were put on a 2-month fast in November-December. The fast caused no deleterious effects on the health of the raccoon dogs. In the spring the food-deprived animals had slightly more cubs per mated female than the fed animals. There was a significant negative correlation between the number of cubs obtained and the mean body mass of the females at the beginning of the mating season. The highest mean number of cubs was obtained by the females that weighed 5-7 kg. The results indicate that the raccoon dog is finely adapted to a long period of food deprivation in the winter. Furthermore, winter sleep and food deprivation could be introduced to farm conditions by providing the raccoon dogs with nestboxes and withholding food for a period of 6-8 weeks in mid-winter.     

Altered expression of melanocortin-1 receptor (MC1R) in a yellow-coloured wild raccoon dog (Nyctereutes procyonoides)

Background – The melanocortin 1 receptor (MC1R) gene plays a key role in determining coat colour in mammals by controlling the proportion of eumelanin and pheomelanin granules. Wild raccoon dogs have a mixed coat colour, with black to brown and grey hairs. Hypothesis/Objectives – The study was performed to identify the cause of the variant yellow coat colour in a wild raccoon dog. Animals – A wild raccoon dog that showed coat colour change to yellow and four wild‐type raccoon dogs that showed normal coat colour were included. Methods – To identify the cause of the variant yellow coat colour, we examined the sequence of the MC1R gene and its expression at the mRNA and protein levels. Results – The coding region of the MC1R gene of this raccoon dog comprised 954 bp, the same as for wild‐type raccoon dogs and domestic dogs. By comparing the gene with that in the wild‐type raccoon dog, a 2 bp deletion was detected in the 5′‐untranslated region, positioned 152 bp upstream of the start codon. However, there was no significant difference in the mRNA expression level. The yellow raccoon dog revealed a significantly decreased MC1R protein level compared with the wild‐type raccoon dogs, indicating an increase in pheomelanin synthesis. Conclusions and clinical importance – These results suggest that the variant coat colour in the yellow raccoon dog was associated with decreased MC1R function.     

Effect of dietary glycine and benzoate level on benzoate metabolism in mink (Mustela vision), blue fox (Alopex lagopus), and raccoon dog (Nyctereutes procyonoides)

Three 2 x 4 factorial experiments were carried out from August to September with 30 juvenile male mink, 24 raccoon dogs, and 24 blue foxes to investigate the effect of dietary glycine supply (low or high) on the efficiency of these species to excrete hippuric acid with incremental benzoate intake (0, 1, 2, or 4 mmol/kg BW). For mink, two additional treatments with 1 or 2 mmol/kg BW of ethyl benzoate were included. A basal low-glycine diet was formulated to meet the minimum protein requirements of fur animals (30% of ME). This diet was supplemented with 0 or 3 g/kg of glycine, or with 0, 1.0, 2.07, or 4.15 g/kg of sodium benzoate for mink and blue foxes, and with 0 or 4.5 g/kg of glycine and 0, 1.58, 3.17, or 6.34 g/kg of sodium benzoate for raccoon dogs, respectively. Two additional diets with .76 or 1.53 g/kg of ethyl benzoate were made for mink. Fecal and urinary benzoic and hippuric acid excretion were measured for 3 d. The 24-h recovery of [14C]benzoic acid injected intraperitoneally was measured from urine, the liver, and the kidneys. All animals appeared healthy and no clinical signs of benzoate overdose were observed. Dietary benzoate level did not affect ADFI or ADG in any species. Glycine supplementation lowered ADFI in mink. The majority of ingested benzoates were absorbed from the gut (over 95%), except in blue foxes, which excreted 6 to 15% of ingested benzoates in feces with incremental increases in benzoate intake. Urinary free benzoic acid excretion accounted for 10% of the ingested benzoates in blue foxes but less than 5% in mink and raccoon dogs. When benzoate intake was 1 mmol/kg BW, mink, blue foxes, and raccoon dogs excreted 71, 77, and 34% of ingested benzoates as hippuric acid in urine, respectively. With higher benzoate intakes, urinary hippuric acid excretion decreased quadratically with mink to 20%, and linearly with blue foxes and raccoon dogs to 45 and 16%, respectively. The hippuric acid pathway appears to be the principal route of benzoate elimination in the mink and blue fox, whereas, in the raccoon dog, other pathways appear to be more important. In mink, the elimination of ethyl benzoate did not differ from that of sodium benzoate. Because glycine conjugation is the primary route of benzoate elimination, it is recommended that benzoate content in fur animal feeds should not exceed 1 g/kg feed on an as-fed basis.