固态发酵葡萄皮渣生产生物饲料的菌种筛选

为了筛选适宜固态发酵葡萄皮渣生产生物饲料的菌种,以葡萄皮渣为主要原料,以真蛋白含量为评价指标,采用产朊假丝酵母、酿酒酵母、嗜酸乳杆菌、植物乳杆菌4株菌的单菌和多菌组合进行固体发酵试验筛选最佳发酵菌种,同时研究了固体培养基灭菌与不灭菌工艺对其产物真蛋白含量的影响。结果表明,葡萄皮渣固体培养基不灭菌发酵产物的真蛋白含量高于灭菌处理;4株菌中产朊假丝酵母单菌发酵后产物的真蛋白含量最高,为13.75%;产朊假丝酵母和嗜酸乳杆菌双菌组合的发酵效果优于三菌和四菌发酵,发酵后产物的真蛋白含量最高,为13.88%。由该试验结果可以确定固态发酵葡萄皮渣的最佳菌种组合为产朊假丝酵母+嗜酸乳杆菌。     

固态发酵甘薯渣增值效果的研究

试验旨在研究利用不同菌种固态发酵甘薯渣,对其增值效果的影响。采用乳酸菌、芽孢杆菌、酵母菌和霉菌4类10株菌对甘薯渣进行固态发酵,测定发酵产物中粗蛋白质、真蛋白质、粗纤维和氨基酸含量变化,比较筛选适宜菌种。结果表明:产朊假丝酵母和霉菌X3提高粗蛋白质和真蛋白质的效果较好,发酵后真蛋白质较发酵前分别提高118.05%和107.02%;酿酒酵母和植物乳杆菌降解粗纤维能力较好,发酵后粗纤维较发酵前分别降解51.54%和49.57%;产朊假丝酵母提高真蛋白质和降解粗纤维的综合能力最好,增值加权值为91.51%;必需氨基酸总量和氨基酸总量均明显提高,其中产朊假丝酵母效果最好,必需氨基酸总量和氨基酸总量分别提高211.32%和154.78%。因此,利用微生物发酵能够改善甘薯渣的营养价值,试验10株菌中产朊假丝酵母改善甘薯渣的营养价值最好。     

复合菌种固态发酵法提高甜高粱秸秆饲料品质的研究

试验探讨了不同菌种及菌种组合对固态发酵甜高粱秸秆酒糟生产蛋白饲料的影响。以产朊假丝酵母、康宁木霉、黑曲霉、枯草芽孢杆菌和白地霉为发酵初筛菌种,探索单一菌种及双菌组合对甜高粱秸秆酒糟木质纤维素、蛋白质含量积累的影响。结果表明,对比未发酵甜高粱秸秆酒糟数据可知,单一菌种和双菌组合均能提高发酵产物的蛋白质含量和降低粗纤维含量。黑曲霉和产朊假丝酵母组合为最佳菌种配伍,且当菌种比例为11时,粗蛋白质含量为18.79%;粗纤维含量为34.68%,较未接菌降低了16.38%,且较单一菌种黑曲霉和产朊假丝酵母分别降低了8.15%、7.01%。通过微生物菌种发酵处理可以降解部分纤维素、提高蛋白质含量,还可在很大程度上缓解饲料中蛋白不足的矛盾。     

复合微生态制剂的制备及其对雏鸡生长性能的影响

研究对动物来源的产朊假丝酵母菌和具有抑菌功能的乳酸菌进行固体发酵条件的筛选,制备活菌数高的功能性复合微生态制剂,通过在雏鸡日粮中添加不同微生态制剂,研究其对雏鸡生产性能的影响。试验经重复检测,验证出产朊假丝酵母固态发酵菌制剂和嗜酸乳杆菌制剂活菌数最高的发酵底物配比及最优发酵条件,并按照11的添加比例进行饲养试验。饲养试验选用1日龄的AA肉用公鸡雏240只,随机分成4组(对照组、产朊假丝酵母菌组、嗜酸乳杆菌组和复合菌添加组),每组5个重复,每个重复12只鸡。试验期28 d,分别在第1、15、29 d称重并记录采食量。研究结果表明:在活菌数最高的发酵底物配比及最优发酵条件下产朊假丝酵母菌固体发酵的活菌数稳定在1.05×1010CFU/g,嗜酸乳杆菌固体发酵的活菌数稳定在3.7×1010CFU/g;添加复合微生态制剂的雏鸡日增重在各个时期均显著高于对照组(P0.05),而料肉比在3~4周和1~4周显著低于对照组(P0.05)。由此可见,复合微生态制剂,可以提高肉仔鸡的生长性能,增加肉鸡养殖的经济效益。     

不同微生物发酵对豆粕营养品质影响的研究

试验选用3种菌株(粪肠球菌、产朊假丝酵母及枯草芽孢杆菌)对豆粕进行发酵,观察豆粕营养品质的变化,结果发现发酵饲料微生物活性越高,干物质回收率(DMR)越低;粪肠球菌发酵活性最高,为32.4亿CFU/g,产朊假丝酵母活性最低,仅为5.8亿CFU/g;干物质回收率以产朊假丝酵母最高,为94.50%,粪肠球菌最低,为90.02%。酸度和粗灰分的上升幅度以粪肠球菌最大,分别上升1.28%和0.44%,粗蛋白提高幅度以产朊假丝酵母最高,为3.95%,枯草芽孢杆菌则以小肽和总氨基酸含量变化最大,分别提高4.35%及12.57%。粗纤维含量无明显变化,说明这3株菌均不产纤维素酶。     

红薯渣固态发酵条件优化

本试验旨在选出最佳单一菌株且确定其混合菌比例和发酵路线,再运用正交试验对混合菌固态发酵红薯渣工艺进行条件优化,以达到提高产物粗蛋白质含量的目的。首先采用4株酵母菌,4株黑曲霉菌,5株枯草芽孢杆菌,1株乳酸菌,在相同发酵条件下固态发酵红薯渣,以产物粗蛋白质含量为主要衡量目标,进行单一菌株的筛选;再利用筛选出的4株最佳单菌进行发酵路线选择;最后对选出的发酵工艺以发酵时间、发酵温度、氮源添加量和菌液接种量4个因素为变量进行L16(44)正交试验,通过测定产物粗蛋白质含量,确定最佳发酵条件。结果表明,产朊假丝酵母、黑曲霉41126、枯草芽孢杆菌Y111、乳酸菌为最佳单一菌株;混合菌比例为(黑曲霉41126∶产朊假丝酵母=2∶1)+(产朊假丝酵母∶枯草芽孢杆菌∶乳酸菌=1∶1∶1)的二次发酵路线产物粗蛋白质含量最高,为15.11%;最佳发酵条件为:发酵时间3 d,发酵温度28℃,氮源添加量1%,菌液接种量3%。此发酵条件下,产物粗蛋白质含量达12.35%,较同等氮源添加量原料发酵前提升了85.99%,且产物能量值和氨基酸含量都有了不同程度的提升,尤其几种必需氨基酸含量明显上升。     

用于蛋白富集的三七渣培养基制备条件优化

利用白腐菌与产朊假丝酵母混合发酵三七渣进行蛋白富集,研究了氮源添加量、磷源添加量、水含量、原料粒径、初始pH值等因素对蛋白富集效果的影响,并采用正交试验优化了培养基制备条件。研究结果表明,利用白腐菌与产朊假丝酵母混合发酵三七渣进行蛋白富集是可行的,优化的培养基制备条件为:氮源添加量40 mg硫酸铵/g干药渣,水含量50%,原料粒径80目,pH自然,在此条件下发酵,发酵培养物中真蛋白含量可达到20.48%。     

不同组合菌种固态发酵马铃薯渣对其营养价值影响研究

研究以马铃薯渣为原料,芽孢杆菌、酵母和霉菌为候选发酵菌种,固态发酵马铃薯渣,研究不同菌种组合固态发酵对其营养价值影响。结果表明:在温度为30℃及自然p H的条件下,发酵72 h,15个组合均能够提高马铃薯渣真蛋白和氨基酸含量、降低粗纤维含量和优化氨基酸组成。其中枯草芽孢杆菌+产朊假丝酵母+绿色木霉和枯草芽孢杆菌+扣囊腹膜酵母+黑曲霉组合改善马铃薯渣氨基酸组成效果较好,总氨基酸含量分别提高111.87%、106.34%和107.93%;枯草芽孢杆菌+酿酒酵母+绿色木霉、枯草芽孢杆菌+产朊假丝酵母+霉菌X3、枯草芽孢杆菌+酿酒酵母+霉菌X3及枯草芽孢杆菌+产朊假丝酵母+绿色木霉组合综合增值能力较强,枯草芽孢杆菌+酿酒酵母+绿色木霉增值加权值达到37.09%,明显或显著高于其他组合(P0.05)。     

麦冬渣固态发酵生产蛋白饲料的动力学研究

对康宁木霉以及康宁木霉/产朊假丝酵母固态发酵麦冬渣生产蛋白饲料的动力学过程进行了比较,提出了用于描述发酵过程中真蛋白增长的动力学模型。研究结果表明,对数方程可以很好地描述发酵过程中真蛋白含量的动态变化情况;在单菌和混菌发酵体系中,真蛋白含量的最大增加量分别为4.97%和6.55%,比增加速率常数分别为0.049 8/h和0.054 2/h;与单菌发酵体系相比,混菌发酵体系能有效促进真蛋白含量的增长。     

三七渣混菌发酵生产蛋白质饲料的工艺条件研究

为研究装料量、温度、接种量、接种比、发酵时间、接种方式对白腐菌与产朊假丝酵母混菌固态发酵三七渣生产蛋白质饲料的影响,本研究在单因素试验基础上,采用正交试验优化了发酵工艺条件。研究结果表明,三七渣固态发酵过程受发酵工艺条件的影响较大。接种比、接种量、接种方式三个因素的交互作用显著(P0.05),这三个因素以及它们之间的交互作用对试验结果影响的大小顺序为:接种量交互作用接种比接种方式。优化的发酵工艺条件为:白腐菌与产朊假丝酵母接种比1∶2,接种量10%,白腐菌发酵2 d后再接入产朊假丝酵母,发酵时间6 d,发酵温度30℃,装料量10 g,在此条件下,发酵培养物的真蛋白质含量可达22.81%。     

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 -