养猪业可持续发展的技术思路

我国养猪业已进入了新的发展阶段．猪肉产品供求基本平衡．提高猪肉产品质量与市场竞争力．增加经济效益和社会效益．改善生态环境已成为我国养猪业实现可持续发展的主要目标。优良的品种、精确的营养、先进的管理、科学的保健、良好的设备是生产优质高效猪肉的五大要素。     

利用地方猪种开发高端猪肉的思考

<正>我国是世界养猪大国也是猪肉消费大国,我国养猪业（生猪生产）经历了从供应不足（短缺）、到供需动态平衡、再到追求品质品味这样一个发展过程。目前,我国经济发展到了一个新的阶段,人们生活水平极大提高,城乡居民对猪肉的消费已由数量的满足（有肉吃）转向质量（吃好肉）的提升,更加注重营养、品质、口感和健康,特别是对优质高端猪肉的需求与日俱增。     

绿色猪肉生产的技术与管理措施

一、生产绿色猪肉的意义 所谓"绿色猪肉"是指按特定的技术标准生产出来的安全、卫生、品质优良、有益人体健康的猪肉产品.随着改革开放进程的不断加快,我国城乡经济日趋繁荣,人们的生产水平逐渐提高,猪肉的消费比重越来越大.据统计,城市人均消费猪肉47 kg/年,农村人均消费28 kg/年,全年猪肉总产量达4000万t以上,居世界首位.如此,堂堂猪肉生产大国面临经济全球化、竞争国际化的大趋势,在冲破世界经济贸易壁垒、加入WTO的新历史时期,理应将发展安全、高效、优质的绿色养猪业列入重要的议事日程并扎扎实实予以实施.这是改善人民生活、保证身体健康的需要,是保护生态环境、使养猪业可持续发展的需要,是提高猪肉品质档次、参与国际竞争的需要.     

维生素E对猪肉品质的影响

近年来,随着现代养猪业的发展和人们生活水平的提高及健康意识的增强,消费者对猪肉品质的要求越来越高,如何生产优质猪肉是当前养猪业的一个热点问题。影响肉质的因素众多,其中营养在肉质的调控中起着重要作用。维生素E对猪肉品质的改善是近年来研究的热点。为此,本文就维生素E     

猪营养研究与饲料科技创新促进我国养猪业发展

改革开放40多年以来,我国养猪业飞速发展,猪营养研究与饲料科技创新对养猪业和饲料工业的发展起着极为关键的推动作用,猪肉产量从1978年的856.3万吨升至2021年的5296万吨。同时,猪营养研究与饲料科技创新提高了猪肉安全性并改善了肉品质,提高了人们的生活品质。猪营养研究与饲料科技创新的不断发展,也促进了饲料资源的合理利用,缓解了人畜争粮的困局。     

改善公猪精液品质的日粮营养调控措施分析

猪人工授精技术是当前养猪生产中的成熟的繁育技术,而优良的公猪精液是该技术发挥优秀繁育性能的必要前提,人们越来越多的研究发现通过对公猪日粮进行营养调控可以有效地改善猪精液品质。文章结合前人的相关研究,从调控公猪日粮蛋白质、微量元素、多不饱和脂肪酸、维生素以及饲料添加剂等方面分析了改善猪精液品质的营养调控措施,旨在为生产出优质种公猪精液提供思路和理论依据,促进人工授精技术的发展和推广应用,提高我国养猪业的发展水平。     

植物提取物对肌纤维类型转化和猪肉品质改善的作用机制研究进展

提高猪肉品质是未来养猪业高质量发展的重点方向。植物提取物含有多酚、类黄酮、多糖等多种活性成分，具有抗氧化、抗炎、免疫调节等多种生物学特性。近年来的研究表明，植物提取物不仅可以提高动物的生长性能，在改善肉品质和风味方面也发挥着重要作用。本文主要综述了植物提取物对肌纤维类型转化的作用机制以及在改善猪肉品质方面的应用研究进展，以期为植物提取物作为饲料添加剂应用于优质猪肉生产中提供理论依据。     

营养调控对宁乡猪肉品质的影响及其分子机制研究北大核心CSCD

宁乡猪是我国优良地方猪品种,具有繁殖力高、肉质好、耐粗饲等优良特点,但由于其背膘厚、瘦肉率低等突出问题,限制了宁乡猪规模化生产和高效利用。因此,通过营养干预等手段改善宁乡猪肉品质,并揭示其调控机制,已成为目前研究的热点。随着生物技术的快速发展,很多与宁乡猪脂质沉积等相关的基因已逐渐被鉴定,并初步揭示了其主要调控网络。因此,本文主要从宁乡猪肉品质特性、营养干预对肉品质的影响及调控肉品质的分子机制研究等方面进行了综述。     

四种优质牧草在养猪业中的应用研究概况

中国是一个猪肉生产和消费大国,随着养猪业的快速发展,猪与人争粮的矛盾日益突出,饲料原料短缺已成为限制我国养猪业持续稳定发展的重要因素。同时,随着人民生活水平的提高,肉食品消费逐渐从数量型向质量型转变,安全、优质的猪肉产品越来越成为消费需求。因此,开发利用新型饲料,减少粮食用量,降低饲养成本,生产安全、优质猪肉产品是发展养猪业的重要途径之一。     

猪肉品质调控的研究

瘦肉型猪的成功培育，使猪肉品质受到了影响。而随着生活水平的提高，消费者对优质风味瘦肉的需求增加。尤其是我国加入WTO后，生产优质猪肉的呼声日益高涨，使我们以立足国际猪肉市场的竞争和养猪业可持续发展战略的高度来审视这一问题。我国虽是第一养猪大国，但猪肉的出口量仅占很小份额。目前的形势与任务使优质猪肉生产更加迫切和重要，而生产优质猪肉的关键是掌握调控肉品质的途径和方法。     

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 -