不同肉鸡用植物性饲料总磷真利用率的测定

本试验利用无磷原料配制无磷饲粮,选择低磷原料配制基础饲粮,用一定比例待测植物性饲料替代基础饲粮配制待测饲粮,通过平衡试验法测定了35日龄艾维茵肉仔鸡对玉米、豆粕、麦麸3种饲料原料的总磷真利用率。结果表明:在控制饲粮含磷量低于肉仔鸡的磷需要量,研究饲料磷的最大利用率时,肉仔鸡的内源磷排出量为(44.84±3.14)mg/d。玉米、豆粕和麦麸的总磷真利用率分别为(16.42±3.36)%、(28.34±4.90)%和(46.48±4.29)%。利用总磷含量的1/3和非植酸磷含量估计肉鸡饲料有效磷并不准确。因麦麸本身含有高活性的植酸酶,肉仔鸡可部分利用其植酸磷。     

生长猪植物性饲料中可消化磷的评定

采用4×4拉丁方设计 ,用玉米淀粉—豆粕作为基础饲粮 ,运用替代基础饲粮的方法测定了生长猪对一些植物性饲料中磷的消化吸收情况 ,并分析了饲料的总磷、植酸磷含量和饲料植酸酶(E.C.3.1.3.26)活性的高低与饲料表观可消化磷的关系。试验结果表明 ,生长猪对以下几种饲料磷的表观消化率如下 :次粉 ,(54.43±3.41) % ;麦麸 ,(50.67±3.96) % ;小麦 ,(49.11±3.37) % ;大麦 ,(42.06±2.12) % ;豆粕 ,(30.83±3.66) % ;玉米 ,(18.99±4.11) % ;细米糠 ,(14.22±2.00) % ;统糠 ,(10.60±3.28) %。试验结果的分析表明 :饲料的总磷含量(X,g/kgDM)、植酸磷含量(Y,g/kgDM)、饲料天然植酸酶活性(Z,PU/g DM)对饲料的表观可消化磷含量(ADP ,g/kgDM)的影响极显著(P<0.01) ,并有极显著的回归关系 :ADP= -0.4155+0.7972X -0.7802Y +0.0013Z(R2=0.9767,P=0.001)。     

饲粮非植酸磷水平对0-4周龄怀乡鸡趾骨特性及内脏器官发育的影响

试验旨在研究不同非植酸磷水平的饲粮对0-4周龄怀乡鸡的趾骨特性及内脏器官发育状况的影响,以此探讨0-4周龄怀乡鸡饲粮非植酸磷的适宜水平。选取同批出生、体况良好的1日龄怀乡鸡300只,随机分成5个处理组,每个处理组6个重复,每重复10只鸡。各处理组分别饲喂非植酸磷含量为0.32%、0.39%、0.46%、0.53%、0.60%的玉米-豆粕型基础饲粮,试验持续期28天。结果表明:1)饲粮非植酸磷水平对怀乡鸡的趾骨脱脂风干重、趾骨脱脂钙含量、趾骨灰分钙含量、趾骨脱脂磷含量、趾骨灰分磷含量有显著影响(P<0.05),其最佳拟合曲线分别为二次曲线(R2=80.22%)、线性折线(R^2=69.19%)、线性折线(R^2=69.78%)、线性折线(R^2=68.70%)、线性折线(R^2=69.02%),拟合结果可用于评价怀乡鸡饲粮非植酸磷的适宜水平。2)饲粮非植酸磷水平对怀乡鸡的心脏指数有显著影响(P<0.05),其线性折线(R^2=57.59%)模型的拟合结果可用于评价怀乡鸡饲粮非植酸磷的适宜水平。建议0~4周龄怀乡鸡饲粮中NPP的适宜水平在0.46%~0.50%范围,满足骨骼发育的需要量为0.46%。     

饲用复合酶对蛋用种鸡日粮磷的利用和生产性能的影响

本试验旨在研究低磷日粮添加复合酶制剂对蛋用种鸡磷的利用和生产性能的影响。选用972只24周龄罗曼褐父母代种鸡,分为3个处理,每处理6个重复,每重复54只种鸡。采用玉米-豆粕-杂粕型基础饲粮,正对照组含总磷0.55%,非植酸磷0.40%,不加酶;负对照组含总磷0.40%,非植酸磷0.21%,不加酶;试验组含总磷0.40%,非植酸磷0.21%,加酶制剂。试验期18周。结果表明:在低非植酸磷的日粮中添加复合酶,粪便中磷含量极显著低于正对照组(P<0.01);粪便中粗蛋白质含量显著低于正对照组和负对照组(P<0.05);显著改善蛋黃顔色(P<0.05);不影响生产性能、骨骼发育和蛋壳质量。添加200 g/t复合酶替代罗曼褐蛋用种鸡日粮中75%的磷酸氢钙能够降低饲料成本,提高养殖企业的经济效益,对罗曼褐蛋用种鸡生产性能无不利影响。     

猪用3种常规植物性饲料磷有效率的测定

本试验采用4×4拉丁方设计,用玉米、豆粕和麦麸替代低磷基础饲粮的方法配制待测饲粮,以平衡试验法测定了生长猪对3种饲料总磷的表观消化率和沉积率。结果表明以总磷和非植酸磷含量估测饲料有效磷并不准确。玉米、豆粕和麦麸总磷表观消化率分别为20.14%±1.97%、31.42%±3.32%、49.83%±2.50%,总磷沉积率分别为19.49%±1.91%、31.22%±3.30%、49.74%±2.46%。     

肉鸭常用饲料原料磷真利用率及真可利用磷预测模型的研究

本试验旨在测定代表性肉鸭饲料原料的总磷和植酸磷含量及其磷真利用率,并建立各原料真可利用磷的预测模型,丰富肉鸭饲料原料数据库,为肉鸭饲粮配方的精确配制提供科学依据.试验收集全国各地常用肉鸭饲料原料,以不同来源饲料原料的化学成分特点及变异规律为依据选出30种代表性样品,采用化学分析法测定样品的总磷和植酸磷含量,以成年樱桃谷...     

生长猪饲粮中植酸磷水平对体内矿物质代谢的影响

二十四头长白猪(70日龄),随机分为四组,饲喂在玉米淀粉—豆饼为主的基础饲粮中添加不同量植酸钠组成植酸磷水平分别为0.065%、0.15%、0.25%、0.35%(占总磷水平分别为13%、30%、50%、70%)的4种饲粮,试验期为五周,研究植酸磷对体内矿物质代谢的影响。结果表明:饲粮中植酸磷影响钙、锌、铜等元素的吸收利用,且这些元素的利用率与饲粮中植酸磷含量呈显著负相关,从而也影响了钙、磷、锌等元素在骨中沉积。饲粮中植酸磷水平达到0.35%时,钙、铜、锌、磷的吸收利用及其在骨中沉积量显著高于其它三个组,而这三组间则无显著差异,但表现出随饲粮中植酸磷水平升高,钙、铜、锌吸收利用及其在骨中沉积量呈下降趋势。     

微生物植酸酶与1～21日龄肉鸡饲粮无机磷当量模型研究

本试验研究饲粮非植酸磷（NPP）和植酸酶添加水平对1～21日龄肉鸡生长性能、养分利用、血液指标及胫骨发育的影响,确定微生物植酸酶与无机磷当量关系。试验设计10个处理,每个处理4个重复,每个重复10只鸡。前4种饲粮NPP水平为2.1、2.9、3.7和4.5 g/kg;后6种饲粮在基础饲粮（NPP 2.1 g/kg,总磷（tP）4.5 g/kg）中添加植酸酶250、500、1 000、2 000、4 000和8 000 U/kg。结果显示：（1）随饲粮NPP水平升高,肉鸡体增重、采食量、饲料转化率、血浆无机磷浓度、胫骨长度、强度、灰分含量与重量、胫骨磷含量以及粗蛋白质、tP和Ca利用率呈二次曲线升高,而死亡率、血浆Ca含量及碱性磷酸酶活性呈二次曲线降低;（2）随植酸酶水平升高,肉鸡生长性能、血浆和胫骨指标、养分利用率呈现与NPP水平增加类似的趋势;（3）当植酸酶水平达到8 000 U/kg时,肉鸡生长性能、血浆和胫骨指标以及粗蛋白质利用率达到对照组（NPP 4.5 g/kg）水平,总磷利用率提高到85%,植酸磷释放率达到94.84%;（4）以胫骨灰分重量为指标,饲粮中无机磷释放量（y,g/kg）与微生物植酸酶添加水平（x,U/kg）之间的关系模型为y = 0.425 4 &#215; log2（1 ＋ x/250） ＋ 0.283 （n=7,R^2 = 0.915 3,P=0.000 7）。结果表明,高水平植酸酶可降解肉鸡饲粮中几乎全部植酸磷,植酸酶添加水平与无机磷当量模型可为确定配方中磷水平提供参考。     

饲粮非植酸磷水平对高峰期蛋鸭产蛋性能、蛋品质和胫骨指标的影响

本试验旨在研究饲粮非植酸磷水平对高峰期蛋鸭产蛋性能、蛋品质和胫骨指标的影响。选取即将达到产蛋高峰期的山麻鸭900只,随机分为6组,每组6个重复,每个重复25只。各组非植酸磷水平分别为0.20%、0.25%、0.30%、0.35%、0.40%、0.45%,试验期11个月。结果表明:1)饲粮非植酸磷水平对蛋鸭产蛋性能和蛋品质均无显著影响(P0.05)。2)饲粮非植酸磷水平对蛋鸭的胫骨重、胫骨长度和折断力无显著影响(P0.05)。骨密度和骨矿盐含量随饲粮非植酸磷水平升高呈现先上升后降低的变化趋势,0.35%组和0.40%组的胫骨密度显著高于0.20%组和0.25%组(P0.05),当饲粮非植酸磷水平升至0.35%以上时,骨矿盐含量显著高于0.20%组(P0.05)。3)饲粮非植酸磷水平对胫骨灰分中钙和磷含量、血清中钙和磷含量均无显著影响(P0.05)。由此可见,在本试验条件下,由于饲粮非植酸磷水平对产蛋性能和蛋品质无显著影响,以骨密度和骨矿盐含量作为参考指标,通过回归方程得出蛋鸭适宜的饲粮非植酸磷水平为0.33%~0.38%。在实际生产中,若只考虑生产性能,建议采用0.20%饲粮非植酸磷水平,可节约饲料成本。     

饲粮非植酸磷水平对产蛋高峰期临武鸭产蛋性能、蛋品质和血清生化指标的影响

本试验旨在研究饲粮非植酸磷水平对产蛋高峰期临武鸭产蛋性能、蛋品质和血清生化指标的影响,以确定其非植酸磷需要量。试验选用遗传背景一致、产蛋率为80%的250只临武鸭,随机分成5个组,每组5个重复,每个重复10只。各组分别饲喂非植酸磷水平为0.20%、0.25%、0.30%、0.35%和0.40%的饲粮,试验全期63 d。结果表明:与0.20%非植酸磷组相比,其他4组合格蛋率分别提高了1.37%(P0.05)、2.15%(P0.05)、2.05%(P0.05)和1.24%(P0.05);0.30%、0.35%和0.40%非植酸磷组的蛋壳厚度高于0.20%和0.25%非植酸磷组(P0.05);随着饲粮非植酸磷水平增加,蛋壳强度呈上升趋势(P0.05);饲粮中非植酸磷水平对血清钙含量无显著影响;0.20%和0.25%非植酸磷组血清中碱性磷酸酶活性高于0.30%、0.35%和0.40%非植酸磷组(P0.05);0.30%、0.35%和0.40%非植酸磷组血清中磷含量高于0.20%非植酸磷组(P0.05)。由此可见,日粮中适宜非植酸磷水平可以提高合格蛋率,保持机体钙、磷代谢平衡,在饲粮钙水平为3.46%条件下,30～38周龄笼养蛋鸭适宜的非植酸磷水平为0.30%～0.35%。     

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.     

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.     

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.     

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 -