不同粗饲料对科尔沁肉牛瘤胃降解率及营养物质消化率的影响

采用尼龙袋试验和消化代谢试验研究不同粗饲料对科尔沁肉牛瘤胃降解率和营养物质消化率的影响。选用3头装有永久性瘘管的科尔沁肉牛,采用尼龙袋法评定肉牛常用粗饲料的干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的有效降解率。结果表明,DM和CP的肉牛瘤胃有效降解率依次为苜蓿草全株玉米青贮玉米青贮玉米秸秆稻草(P0.05);NDF和ADF的肉牛瘤胃有效降解率以玉米青贮最高,NDF有效降解率苜蓿草最低,ADF降解率以玉米秸秆最低,全株玉米青贮和苜蓿草居中。消化代谢试验选用5头科尔沁肉牛,按3×5非完全拉丁方设计,分3期分别饲喂5种粗饲料。结果表明,5种粗饲料的DM、CP消化率以苜蓿草最高,稻草最低,玉米青贮、全株玉米青贮和玉米秸秆居中;NDF和ADF消化率玉米青贮最高,稻草最低。因此,5种粗饲料的营养价值大小顺序依次为:苜蓿草、全株玉米青贮、玉米青贮、玉米秸秆和稻草。     

酒精清液发酵玉米秸秆、全株玉米青贮和玉米秸秆瘤胃降解率的研究

本试验旨在研究3种玉米秸秆的营养成分及瘤胃降解特性。首先测定玉米秸秆、全株玉米青贮及发酵秸秆的常规营养成分,然后采用尼龙袋法其干物质(DM)、粗蛋白质(CP)和中性洗涤纤维(NDF)的瘤胃消失率与瘤胃降解参数。结果表明:秸秆经酒精清液发酵后,其CP、EE含量显著高于玉米秸秆和玉米青贮(P<0.05),且NDF、ADF含量显著降低(P<0.05)。发酵玉米秸秆各种营养成分72 h瘤胃消失率均显著高于玉米秸秆(P<0.05),而DM、CP和ADF的72 h瘤胃消失率与全株玉米青贮水平相当,差异不显著(P>0.05)。发酵玉米秸秆DM、CP、NDF和ADF的有效降解率分别为46.93%、58.35%、36.41%和36.01%,显著高于玉米秸秆(P<0.05)。CP的有效降解率略低于全株玉米青贮;CP、NDF和ADF的潜在可降解部分(a+b)值显著高于玉米秸秆(P<0.05)。因此,经酒精清液发酵后,秸秆的营养价值得到明显改善,部分营养成分及瘤胃利用效率与全株玉米青贮相似。     

利用尼龙袋法比较3个全株玉米品种青贮前后肉牛瘤胃降解特性

本试验旨在利用尼龙袋法比较不同品种全株玉米青贮前后瘤胃降解特性的差异。试验采用2×3双因素试验设计,选择玉米7367号、玉米7377号、玉米7387号3个全株玉米品种为研究对象,采用尼龙袋法比较3种全株玉米青贮前和青贮后的营养成分和瘤胃降解特性,旨在探讨适合河北省种植的全株玉米青贮品种。结果表明:1)青贮前玉米7377的粗蛋白(CP)和非蛋白氮(NPN)含量显著高于玉米7367和玉米7387(P0.05);玉米7677和玉米7377的中性洗涤纤维(NDF)含量显著低于玉米7387(P0.05);玉米7677的酸性洗涤纤维(ADF)含量显著低于玉米7377和玉米7387(P0.05)。与青贮前同品种全株玉米相比,3种全株玉米青贮后的CP、粗脂肪(EE)、粗灰分(Ash)、钙(Ca)、磷(P)、NPN含量显著提高(P0.05),NDF含量显著下降。玉米7367青贮的CP和NPN含量显著高于玉米7377青贮和7387青贮(P0.05);玉米7677青贮和7377青贮的NDF和ADF含量显著低于玉米7387青贮(P0.05)。2)不同品种全株玉米青贮前的DM、CP、NDF、ADF瘤胃降解率有显著差异,玉米7367的干物质(DM)和NDF有效降解率显著高于玉米7377和玉米7387(P0.05);玉米7377的CP有效降解率显著高于玉米7367和玉米7387(P0.05)。青贮处理能显著提高3种全株玉米DM、CP、NDF和ADF的快速降解部分(P0.05),降低其慢速降解部分(P0.05),显著提高其有效降解率(P0.05)。玉米7367青贮的DM、CP、NDF、ADF有效降解率显著高于玉米7377和玉米7387(P0.05)。综合表明青贮处理能很好地保存3种全株玉米的营养成分,显著提高DM、CP、NDF和ADF的瘤胃降解率;玉米7367青贮前和青贮后的营养成分和瘤胃降解率显著高于玉米7377和玉米7387,在本试验中是比较适合河北省种植的全株玉米青贮品种。     

发酵湿玉米纤维饲料同常用粗饲料在瘤胃降解特性和小肠消化率上的比较研究

试验旨在研究发酵湿玉米纤维饲料同常用粗饲料在瘤胃降解特性和小肠消化率的异同点。选用2头体重550 kg左右,安装有永久性瘤胃瘘管的荷斯坦奶牛作为试验动物,采用常规方法测定发酵湿玉米纤维饲料(FWCGF)、湿玉米纤维饲料(WCGF)、苜蓿和全株玉米青贮的营养价值,采用尼龙袋法和三步体外法测定4种饲料的干物质(DM)、粗蛋白(CP)、中性洗涤纤维(NDF)的瘤胃降解率以及瘤胃非降解蛋白(RUP)的小肠消化率。试验结果表明:(1)FWCGF的CP含量显著高于WCGF、苜蓿和全株玉米青贮(P0.05);苜蓿的SP、NPN、NDICP和ADF含量最高,FWCGF的ADF含量显著低于WCGF(P0.05);FWCGF的EE含量显著高于WCGF的EE含量(P0.05)。(2)4种饲料的DM瘤胃降解率和有效降解率由高到低的顺序是FWCGFWCGF苜蓿全株玉米青贮;4种饲料的CP有效降解率由高到低的顺序是FWCGFWCGF全株玉米青贮苜蓿;4种饲料的NDF有效降解率由高到低的顺序是全株玉米青贮苜蓿FWCGFWCGF。(3)WCGF和FWCGF的RUP小肠消化率和小肠可消化蛋白质差异不显著(P0.05),苜蓿最高。综上可以得出,FWCGF和WCGF均含有高含量的可利用蛋白质和可利用纤维,并且FWCGF可以提高可利用蛋白的含量,有较高的DM和CP的瘤胃降解率,通过酿酒酵母发酵处理可有效保持WCGF的营养成分。     

新疆及内蒙古地区玉米青贮在肉用绵羊瘤胃中降解规律的比较

为了进一步了解我国西部地区玉米青贮在肉用绵羊瘤胃内的降解特性,试验选择了内蒙古、新疆的不同地区玉米青贮,并用尼龙袋法测定其中的干物质(DM)、粗蛋白(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)等营养成分在肉用绵羊瘤胃内的有效降解率,以期为提高玉米青贮在我国西部地区肉用绵羊生产中的利用率提供一定的参考依据。试验结果表明,新疆地区玉米青贮的营养价值高于内蒙古地区,且DM、CP、NDF、ADF的有效降解率都高于内蒙古地区,证明新疆地区的玉米青贮要比内蒙古地区的更易于在肉用绵羊瘤胃内降解消化。     

禾王草与奶牛常用粗饲料瘤胃降解特性的对比研究

本试验旨在研究2种刈割高度的禾王草干草和青贮、羊草干草、苜蓿干草以及全株玉米青贮共7种粗饲料的瘤胃降解特性。选用4头装有永久性瘤胃瘘管的荷斯坦奶牛为试验动物,采用尼龙袋法评定其干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的72 h瘤胃降解率。结果表明:1)禾王草干草CP含量显著高于羊草干草(P0.05),NDF含量显著低于羊草干草(P0.05);禾王草青贮CP和NDF含量显著高于全株玉米青贮(P0.05)。2)苜蓿干草DM有效降解率最高,与依次降低的全株玉米青贮、2.0 m禾王草青贮、2.5 m禾王草青贮、2.0 m禾王草干草、2.5 m禾王草干草和羊草干草差异显著(P0.05),羊草干草的DM有效降解率显著低于其他粗饲料(P0.05);CP有效降解率以苜蓿干草最高,与2.0 m禾王草青贮差异不显著(P0.05),显著高于依次降低的2.5 m禾王草青贮、2.0 m禾王草干草、全株玉米青贮、2.5 m禾王草干草和羊草干草(P0.05);全株玉米青贮与禾王草青贮的NDF有效降解率差异不显著(P0.05),而显著高于其他粗饲料(P0.05);禾王草青贮72 h时ADF有效降解率显著高于其他粗饲料(P0.05)。由此可知,禾王草有作为奶牛粗饲料的潜力,禾王草经青贮后可以保存营养成分,并可以提高营养成分的瘤胃利用效率。     

不同食品加工副产品的瘤胃降解特性与小肠消化率的测定

本试验旨在测定胡麻饼(FM)、DDGS、麦麸皮(WB)、白酒糟(DG)、干啤酒糟(DBG)、苹果渣(AP)的瘤胃降解规律以及小肠消化率。试验选用3头体重为650 kg左右、安装有永久性瘤胃瘘管的荷斯坦奶牛,采用尼龙袋法测定其有机物(OM)、粗蛋白(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃降解率以及粗蛋白(CP)和氨基酸(AA)的小肠消化率。结果表明:不同食品加工副产品常规营养成分存在差异;不同食品加工副产品的瘤胃有效降解率之间差异显著(P0.05),高低顺序为OM:WBDDGSDBGAPFMDG,CP:WBDBGFMAPDDGSDG,NDF:WBFMDDGSDBGAPDG,ADF:DBGAPFMDDGSWBDG;测定样品的CP和各种AA成分小肠消化率差异显著(P0.05),其中CP和TAA高低顺序为CP:FMDDGSWBDBGDGAP,TAA:FMDDGSDGWBDBDAP。由此可见,不同食品加工副产品的营养成分含量、瘤胃降解特性不同,为小肠提供可消化粗蛋白潜力也不同。     

几种主要粗饲料的瘤胃降解特性比较研究

选用体重(550±25)kg的4头装有永久性瘤胃瘘管的泌乳中期黑白花奶牛作为试验动物,研究比较了苜蓿与其他几种常用粗饲料的DM、CP、NDF和ADF的瘤胃降解特性。结果表明:DM、CP的奶牛瘤胃有效降解率以苜蓿最高,玉米秸秆最低,全株玉米青贮、羊草和玉米黄贮居中。不同粗饲料NDF的瘤胃有效降解率差异较小,最高的为全株玉米青贮。玉米黄贮、羊草和全株玉米青贮的ADF瘤胃有效降解率较高,玉米秸秆和苜蓿较低。     

奶牛对不同糟渣类饲料营养成分的瘤胃降解率和小肠消化率对比研究

本试验旨在对比奶牛对不同糟渣类饲料(玉米酒糟、高粱酒糟、醋糟、糖糟、啤酒糟)的营养成分瘤胃降解率和小肠消化率.选用3只装有永久性瘤胃瘘管的中国荷斯坦奶牛,用尼龙袋法测定干物质(DM)、粗蛋白质(CP)、必需氨基酸(EAA)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)在不同时间点的瘤胃降解率和小肠消化率.结果表明:1...     

青贮马铃薯渣作为肉羊饲料的营养价值评定

研究旨在探索青贮马铃薯渣的营养成分及其瘤胃降解率,为肉羊养殖饲料的选取提供一定的理论依据。以青贮马铃薯渣为对象通过尼龙袋法研究其瘤胃降解特性。结果表明:青贮马铃薯干物质(DM)、有机物(OM)、粗蛋白(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)的降解率随着时间的增加逐渐增大,DM、OM、CP、NDF、ADF的瘤胃有效降解率分别为58.58%、62.17%、55.45%、39.67%、41.92%,DM和CP的瘤胃有效降解率显著高于NDF和ADF。说明青贮马铃薯营养成分丰富且降解率较高,可在肉羊养殖中作为较好的粗饲料广泛利用。     

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.     

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

Tropical Animal Health and Production -     

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

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