全收粪法和指示剂法测定陕北白绒山羊日粮养分消化率的研究

通过全收粪法和指示剂法,测定陕北白绒山羊日粮CP、EE、NDF、ADF、DM、OM的消化率.结果表明:AIA法测定各营养成分消化率比全收粪法偏高,两种方法间差异显著.外源指示剂法(Cr2O3)测定CP、EE、NDF、ADF、DM、OM的消化率与全收粪法差异不显著,Cr2O3的回收率87.75%.研究认为Cr2O3可以作为测定陕北白绒山羊日粮消化率方法.     

全收粪法和AIA指示剂法测定奶牛日粮有机物消化率差异比较

采用奶牛消化代谢试验测定6头奶牛日粮中有机物消化率,对比分析用全收粪法和AIA法测定的有机物消化率差异.结果表明,用全收粪法、AIA法测定的日粮有机物表观消化率分别为68.2%、73.9%,AIA法测定值显著高于全收粪法(P<0.05),内源指示剂AIA回收率为110.9%.     

全收粪法与内源指示剂法测定德州驴饲粮中养分消化率的比较研究

本试验通过测定不同内源指示剂的回收率,筛选出最佳的内源指示剂,并且与全收粪法进行对比,测定德州驴饲粮中养分消化率。试验选用生长状况良好的德州公驴12头,体重(128.5±5.0) kg,随机分为3个处理,每个处理4个重复。试验选用单一饲草苜蓿和2种全混合日粮(TMR),分别使用酸不溶木质素(ADL)、含有浓硫酸不溶灰分的木质素(ADL+SAIA)、盐酸不溶灰分(AIA)3种内源指示剂和全收粪法进行消化试验,用聚酯筛网袋法测定饲粮中各内源指示剂的回收率。预试期10 d,正试期6 d。结果表明:1)3种饲粮中ADL的平均回收率为98.28%,可作为理想的内源指示剂,而AIA的平均回收率偏高。2) ADL内源指示剂法测定的3种饲粮中各养分消化率与全收粪法无显著差异(P0.05)。由此可见,ADL可作为内源指示剂对德州驴饲粮中养分消化率进行测定。     

全收粪法与不同内源指示剂法测定山羊饲粮中养分消化率的比较

本试验旨在比较全收粪法与不同内源指示剂法测定山羊饲粮养分消化率差异,并建立消化能(DE)的估测模型。选用生长状况良好的杂交波尔山羊72只,体重约35 kg,随机分为4组,每组3个重复,每个重复6只羊。使用3种内源指示剂[盐酸不溶灰分+酸性洗涤木质素(ADL+AIA)、酸性洗涤木质素(ADL)、盐酸不溶灰分(AIA)]法和全收粪法,分别对4种不同的颗粒型全混合日粮(TMR)进行试验,用聚酯筛网袋法测定内源指示剂的回收率。结果表明:1)内源指示剂ADL+AIA、ADL和AIA的平均回收率分别为99.84%、100.33%和100.60%,均可作为理想的内源指示剂,其中ADL+AIA作为内源指示剂平均回收率为99.84%,变异系数(CV)最低(4.59%)。2)ADL+AIA、ADL和AIA法测定4种饲粮的各养分消化率和DE与全收粪法无显著差异(P0.05)。3)采用饲粮中粗蛋白质(CP)、粗脂肪(EE)、中性洗涤可溶性碳水化合物(NDSC)、半纤维素(HCEL)和纤维素(CEL)含量建立的DE估测模型为:DE(MJ/kg)=0.017 2CP+0.034 6EE+0.015 3NDSC+0.010 8HCEL+0.007 8CEL。由此可见,ADL+AIA、ADL和AIA均可作为理想的内源指示剂进行育肥羊饲粮中养分消化率和DE的测定,通过测定饲粮中CP、EE、NDSC、CEL和HCEL含量,可以较好地预测育肥羊的DE。     

猪生长阶段与饲粮类型对酸不溶灰分法测定养分消化率的影响

本试验旨在探讨猪饲粮中添加硅藻土来源的盐酸不溶灰分(AIA)后,以饲粮和粪中AIA含量测定养分消化率的可行性。试验采用2×2两因素完全随机设计,其中饲粮设2个处理,即玉米-豆粕型饲粮和玉米-玉米干酒糟及其可溶物(cDDGS)-米糠粕型饲粮;猪生长阶段设2个处理,即生长期(60~100日龄)和育肥期(100~140日龄)。每个生长阶段分为2个试验期,每期试验包括5 d预试期、5 d全收粪期和3 d部分粪样定点采集期,测定饲粮及粪样的干物质、AIA、总能和粗蛋白质含量,从而计算饲粮的养分消化率及AIA的回收率。结果表明:1)玉米-豆粕型饲粮和玉米-cDDGS-米糠粕型饲粮中AIA的平均回收率分别为97.29%和97.54%,差异不显著(P0.05);2)全收粪法和AIA法测定的养分消化率差异不显著(P0.05),猪生长阶段和饲粮类型对其测定的养分消化率的绝对差影响不显著(P0.05);3)部分粪样定点采集AIA法测定的干物质消化率与全收粪AIA法差异不显著(P0.05),猪生长阶段和饲粮类型对其测定的干物质消化率的绝对差影响不显著(P0.05)。综合以上研究结果,在2种猪饲粮中添加0.8%的硅藻土后,以AIA法测定饲粮养分消化率不受猪生长阶段及饲粮类型的影响,且AIA法与全收粪法的测值是可比的。     

全收粪法与Cr2O3指示剂法测定家禽表观代谢能方法比较

通过全收粪法和Cr2O3指示剂法,对20种不同来源玉米-豆粕型日粮的肉鸡的表观代谢能(AME)进行测定.结果表明全收粪法测定玉米AME在绝干基础上是14.92～16.10 MJ/kg,平均15.60 MJ/kg,RSD为2.15%;指示剂法所测玉米AME在绝干基础上是15.05～16.16 MJ/kg,平均15.65 MJ/kg,RSD为2.11%;两种方法所测代谢能值相关分析,相关方程式AME(全)=1.00142×AME(指)-0.06918(R2=0.9708),二者高度相关;配对T检验,指示剂法比全收粪法值高,但差异不显著(P＞0.05).可见,Cr2O3指示剂法与全收粪法在测定肉禽AME时具有高度相关性,指示剂法可作为一种快速准确的评定家禽表观代谢能的方法在试验研究和生产实践中推广.     

应用不同方法测定獭兔单一原料表观消化率及消化能的研究进展

评价某种饲粮对獭兔营养物质表观消化率及表观消化能是动物营养学研究的重要内容,在饲料营养价值评定、非常规饲料资源开发利用等方面发挥重要作用。表观消化率及消化能测定结果的不同,一方面是由于收粪方法不同产生的差异,如全收粪法和直肠取粪法;另一方面是由于估算方法的差异,如单一原料饲喂法、套算法、指示剂法等,其中不同类型指示剂由于其回收率的不同也会造成差异,如酸不溶灰分(AIA)、二氧化钛(TiO_2)、三氧化二铬(Cr_2O_3)等。本文旨在探究不同方法测定獭兔表观消化率及消化能的研究进展,并阐述各类方法的应用效果。     

鱼饲料表观消化率测定方法的综述

消化率是评价饲料营养价值的重要指标,也是确定日粮配方的依据。由于鱼所生长环境的特殊性,使得测定鱼的消化率比较困难。体外测定法主要采用酶解法,而体内测定法主要采用间接指示剂的方法进行测定,以酸不溶灰分(AIA)、Cr2O3、Y2O3、La2O3、Yb2O3为指示剂测定表观消化率,不同的指示剂在不同的鱼、不同的饲料中其测定值的精确性有较大的差异。文中简要的介绍了3种体外测定方法并重点叙述了指示剂的使用,为鱼消化率测定方法提供参考。     

双内源指示剂法测定兔饲粮消化能值及其预测模型的研究

本试验旨在研究利用双内源指示剂法测定兔饲粮养分消化率及消化能(DE)值,并建立兔饲粮DE值的预测模型。选用体重相近的4月龄獭兔30只,随机分为3组,每组10个重复,每个重复1只兔。每组饲喂1种饲粮,用全收粪法进行消化试验,用聚酯纤维筛网袋法测定了饲粮中的2种内源指示剂,即酸不溶木质素(ADL)和盐酸不溶灰分(AIA)+ADL的回收率。同时选取了山东省不同饲料公司生产的17种兔颗粒配合饲料,在各自兔养殖场进行饲养试验,利用双内源指示剂法测定兔饲粮DE值,建立兔饲粮DE值的预测模型。结果表明:1)全收粪法测得3种饲粮ADL的平均回收率为99.87%,ADL+AIA的平均回收率为96.81%,二者可作为理想的双内源指示剂。2)利用双内源指示剂法可以准确测定兔饲粮的各种养分消化率和DE值。3)兔饲粮DE值可以用饲粮中可消化有机物质(DOM)含量进行准确的预测:DE(M J/kg)=0.0204DOM(g/kg)或DE(M J/kg)=0.939 5+0.018 2DOM(g/kg)。4)利用兔饲粮中养分[粗蛋白质(CP)、粗脂肪(EE)、可溶性碳水化合物(NDSC)、半纤维素(HCEL)和纤维素(CEL)]含量建立兔饲粮DE值的预测模型为DE(MJ/kg)=0.016 6CP(g/kg)+0.0334EE(g/kg)+0.015 3NDSC(g/kg)+0.005 4HCEL(g/kg)+0.003 1CEL(g/kg)。由此可见,利用双内源指示剂法可以较好地预测兔饲粮的DE值。     

日粮精料进食水平对肉牛消化道营养物质流量和表观消化率的影响

为了研究日粮精料进食水平对肉牛真胃食糜营养流量和营养物质表观消化率的影响,试验选择体重650kg左右荷斯坦(Holstein)公牛3头,安装有瘤胃、真胃瘘管,按3×3拉丁方实验设计分别饲喂粗料进食量相同而精料不同的3种日粮,以三氧化二铬(Cr2O3)作真胃食糜标记物,全收粪法收集粪样,测定真胃食糜和粪中的有机物(OM)、粗蛋白质(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)流量及在瘤胃内、真胃后段消化道(简称肠道)内的表现消化率.结果表明日粮精料进食水平对瘤胃及全消化道的OM、NDF、ADF表观消化率没有显著影响(P＞0.05),日粮精料水平明显影响到达真胃的OM和蛋白质量(P＜0.05),但全消化道CP表观消化率没有差异(P＞0.05).     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -