苜蓿和全株玉米混合青贮效果研究

为了寻求提高苜蓿和全株玉米发酵品质和营养成分的最优混贮比例,试验以初花期第三茬紫花苜蓿与全株玉米为原料,制成不同混合比例(苜蓿和全株玉米比分别为0∶100、40∶60、51∶49、61∶39、80∶20、100∶0)的青贮饲料,水分含量为50%~70%,在室内装袋发酵90 d,测定混合青贮的各项营养指标。结果表明:不同混合比例及时间对混合青贮的品质有显著影响,苜蓿与全株玉米混贮80∶20组合粗蛋白和粗灰分含量高于全株玉米单贮(P0.05),低于苜蓿单贮(P0.05);51∶49组合的酸性洗涤纤维含量最低,与苜蓿单贮相比差异极显著(P0.01),与全株玉米单贮相比差异不大;苜蓿与全株玉米40∶60、61∶39组合p H值与苜蓿单贮相比差异极显著(P0.01)。苜蓿和全株玉米混贮40∶60组合的品质最佳。     

全株玉米与紫花苜蓿拉伸膜裹包混合青贮的研究

试验以全株玉米和紫花苜蓿为原料,探讨不同混合比例青贮效果,确定最佳混合比例。试验设5个处理组:全株玉米单贮(Y组)、紫花苜蓿单贮(Z组)、75%全株玉米+25%紫花苜蓿(Y75Z25组)、67%全株玉米+33%紫花苜蓿(Y67Z33组)、50%全株玉米+50%紫花苜蓿(Y50Z50组)。结果表明,全株玉米与紫花苜蓿混合青贮的粗蛋白、酸性洗涤纤维、粗灰分含量介于全株玉米单贮和紫花苜蓿单贮之间。表现为,青贮饲料粗蛋白(CP)、粗灰分(CA)含量随着紫花苜蓿比例的提高,而显著提高(P0.05);酸性洗涤纤维(ADF)含量随着紫花苜蓿比例的降低,而显著降低(P0.05)。紫花苜蓿单贮,发酵品质较差。与紫花苜蓿单贮相比,混合青贮饲料随着全株玉米比例的提高,青贮效果逐步改善,当比例达到67%时,显著降低了青贮饲料的pH值、氨态氮/总氮值(P0.05),显著提高了乳酸含量、乳酸/总酸值(P0.05),并使丁酸含量低于检测水平,获得优质青贮饲料。综合各项指标,以67%全株玉米+33%紫花苜蓿与75%全株玉米+25%紫花苜蓿混合青贮效果较为理想。     

紫花苜蓿和全株玉米混合青贮研究

试验以紫花苜蓿和全株玉米为原料,探讨不同混合比例对混合青贮发酵品质的影响,确定最佳混合比例。试验设5个处理组:紫花苜蓿单贮组(Z),全株玉米单贮组(Y),20%紫花苜蓿+80%全株玉米(ZY28),40%紫花苜蓿+60%全株玉米(ZY46),50%紫花苜蓿+50%全株玉米(ZY55),将各组青贮发酵60 d后开窖并测定青贮发酵品质。测定结果表明:紫花苜蓿单独青贮,发酵品质较差,青贮饲料评分较低。与紫花苜蓿单独青贮相比,紫花苜蓿与全株玉米混合青贮中,随着全株玉米比例的提高,青贮发酵品质逐步改善,当达到60%时,显著降低了青贮饲料的pH值和氨态氮/总氮值,并使丁酸含量低于检测水平,提高了乳酸含量,获得优质混合青贮饲料。随着玉米比例的进一步提高,其pH值和感官评分没有明显变化,而干物质含量略有降低。从营养均衡和发酵品质综合考虑,建议以40%紫花苜蓿与60%全株玉米混合青贮较为适宜。     

不同比例全株玉米与高粱混贮对青贮发酵品质的影响

试验旨在探究不同比例全株玉米与高粱混贮对青贮发酵品质和营养价值的影响,确定全株玉米与高粱青贮的适宜混合比例。试验共设5组,其中3个混贮组,2个单贮组。混贮组全株玉米与全株高粱按3∶1(YG31)、1∶1 (YG11)、1∶3 (YG13)比例分别混合,单贮组为全株青贮玉米（YG10）和全株高粱单独青贮（YG01）,每组3个重复。发酵期60 d。结果显示：与单贮相比,玉米与高粱混贮能够不同程度地提高青贮感官评分与发酵品质,YG31的综合评分显著高于YG10、YG01 (P<0.05),pH值显著低于YG10 (P<0.05),乳酸/总酸显著高于YG01 (P<0.05)。与YG10相比,YG31、YG11的干物质、粗脂肪、中性洗涤纤维含量显著降低（P<0.05）,而相对饲喂质量（RFQ）显著升高（P<0.05）。随着混合青贮中高粱比例增加,青贮饲料有氧稳定性呈先减后增再减的趋势。YG31青贮的有氧稳定性显著低于YG13 (P<0.05)。研究表明,全株玉米与高粱混合青贮能够不同程度地改善青贮饲料发酵品质和营养价值,其适宜混贮比例为3∶1～1∶1。     

西藏地区荞麦与玉米混合青贮对发酵品质和微生物多样性的影响

为探究西藏林芝市全株荞麦与全株玉米混合青贮对青贮饲料发酵品质和微生物多样性的影响,分别设定全株荞麦单独青贮组(A)、全株荞麦∶全株玉米=4∶1混合青贮组(B)、全株荞麦∶全株玉米=3∶2混合青贮组(C)、全株荞麦∶全株玉米=2∶3混合青贮组(D)和全株荞麦∶全株玉米=1∶4混合青贮组(E)共5个处理组。分别在青贮第7、14、30和60天时,开窖取样,测定青贮饲料的发酵品质和微生物菌群结构。结果表明,与全株荞麦单独青贮组相比,全株荞麦与全株玉米混合青贮组在一定程度上改变了青贮的发酵品质,混合青贮组降低了青贮饲料的pH值,提高了乳酸含量,且氨态氮/总氮的值和丁酸含量均符合优质青贮饲料的要求量。从微生物菌群结构来看,混合青贮改变了青贮饲料的菌群结构,相比与全株荞麦单独青贮组,混合青贮组提高了厚壁菌门和LAB菌种的丰度,有效地抑制了腐败菌的生长,且这种效果随着全株玉米混合比例越高而越显著。综合考虑全株荞麦利用最大化和发酵品质,建议将全株荞麦和全株玉米以2∶3混合青贮较为适宜。     

西藏地区荞麦与玉米混合青贮对发酵品质和微生物多样性的影响

为探究西藏林芝市全株荞麦与全株玉米混合青贮对青贮饲料发酵品质和微生物多样性的影响,分别设定全株荞麦单独青贮组(A)、全株荞麦∶全株玉米=4∶1混合青贮组(B)、全株荞麦∶全株玉米=3∶2混合青贮组(C)、全株荞麦∶全株玉米=2∶3混合青贮组(D)和全株荞麦∶全株玉米=1∶4混合青贮组(E)共5个处理组。分别在青贮第7、14、30和60天时,开窖取样,测定青贮饲料的发酵品质和微生物菌群结构。结果表明,与全株荞麦单独青贮组相比,全株荞麦与全株玉米混合青贮组在一定程度上改变了青贮的发酵品质,混合青贮组降低了青贮饲料的pH值,提高了乳酸含量,且氨态氮/总氮的值和丁酸含量均符合优质青贮饲料的要求量。从微生物菌群结构来看,混合青贮改变了青贮饲料的菌群结构,相比与全株荞麦单独青贮组,混合青贮组提高了厚壁菌门和LAB菌种的丰度,有效地抑制了腐败菌的生长,且这种效果随着全株玉米混合比例越高而越显著。综合考虑全株荞麦利用最大化和发酵品质,建议将全株荞麦和全株玉米以2∶3混合青贮较为适宜。     

全株玉米与秣食豆单贮混贮效果的研究

以中北青贮410玉米(Zea mays L.)和秣食豆(Glycine max Merrill)为青贮材料,设置单贮全株玉米、单贮秣食豆、80%全株玉米和20%秣食豆混贮、70%全株玉米和30%秣食豆混贮、60%全株玉米和40%秣食豆混贮5个处理组,研究全株玉米和秣食豆混合青贮的青贮效果以及最佳比例。结果表明:单贮全株玉米的发酵品质最好,单贮秣食豆的发酵品质最差。秣食豆添加比例为20%和30%的发酵品质效果相似,比秣食豆添加比例为40%的混贮效果好;就化学成分而言,单贮全株玉米的青贮效果较差,单贮秣食豆的青贮效果最好,其蛋白质含量最高(P<0.05),中性洗涤纤维和酸性洗涤纤维含量最低(P<0.05),3组混贮中秣食豆的添加比例越高效果越好。5个青贮处理综合比较发酵品质和化学成分,以70%全株玉米和30%秣食豆混合青贮的效果最好,秣食豆添加比例为20%和40%的混合青贮效果次之。     

玉米与高粱混合青贮的研究

以全株玉米和高粱为青贮原料,设置玉米、高粱单贮以及70%玉米+30%高粱、50%玉米+50%高粱、30%玉米+70%高粱的混贮试验,研究玉米与高粱单贮和混合青贮的效果,以及混贮的最佳比例。结果表明,全株玉米单贮发酵品质最好,高粱单贮的发酵品质最差,三个混贮处理的发酵品质也都好。从营养品质看,玉米单贮的蛋白质含量最高,中性洗涤纤维和酸性洗涤纤维的含量最低;高粱单贮的营养品质较差;对3个混贮处理组的发酵品质、营养品质以及V-Score评分进分综合比较发现,以50%玉米+50%高粱混贮的青贮效果最好,70%玉米+30%高粱的混合青贮效果较好,得出这两种混贮处理是适宜凉山地区推广的玉米与高粱混合青贮模式。     

白三叶与全株玉米混合青贮的效果研究

以白三叶和全株玉米为青贮原料,设置全株玉米单贮、30%白三叶+70%全株玉米、50%白三叶+50%全株玉米、70%白三叶+30%全株玉米以及白三叶单贮共5个试验组,研究白三叶和全株玉米混合青贮的青贮效果及其最佳比例。结果表明,全株玉米单贮发酵品质良好,白三叶单贮发酵品质尚可;混贮中70%白三叶+30%全株玉米的发酵品质良好,其余为尚可;综合比较发酵品质、营养品质以及V-Score评分,得出以70%白三叶+30%全株玉米混贮发酵的品质最佳,是攀西地区开展白三叶与全株玉米混贮的最佳配比。     

红三叶与全株玉米混合比例对青贮品质的影响

以红三叶和全株玉米为青贮原料,设置全株玉米单贮、30%红三叶+70%全株玉米、50%红三叶+50%全株玉米、70%红三叶+30%全株玉米、红三叶单贮的青贮试验,研究红三叶的青贮效果以及红三叶与全株玉米混贮的最佳比例。结果表明:红三叶不能单独调制青贮饲料,三个混贮处理的发酵品质中,30%红三叶+70%全株玉米和50%红三叶+50%全株玉米的青贮品质为良好。混贮的粗蛋白含量为8.56%~12.40%,比全株玉米单贮粗蛋白含量提高11.17%~61.04%,混贮的粗蛋白含量随着红三叶添加比例升高呈现逐渐增加的趋势。混贮的酸性洗涤纤维为21.85%~23.62%,中性洗涤纤维为37.25%~39.71%,都分别低于两个单贮处理,酸性洗涤纤维和中性洗涤纤维含量较低的是30%红三叶+70%全株玉米和50%红三叶+50%全株玉米。综合比较发酵和营养品质以及V-Score评分,以30%红三叶+70%全株玉米混贮的青贮效果最好,50%红三叶+50%全株玉米的混合青贮效果次之,这两种混贮处理是适宜攀西地区推广的红三叶青贮模式。     

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.     

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