中草药添加剂对生长肥育猪横纹肌肌纤维特性及肉质的影响

 选用20 kg左右的“杜长大”三元杂交猪80头,随机分成对照组、试验组,测定添加中草药添加剂对横纹肌肌纤维特性和肉质品质的影响。结果表明,试验组的大理石纹评分比对照组提高了23.33%（P＜0.01）、肌间脂肪的含量增加了52.77%（P＜0.01）、嫩度改善了13.53%（P＜0.05）;而失水率、贮存损失分别降低了5.03%（P＜0.05）和20.35%（P＜0.05）.试验猪的肌纤维直径比对照组降低了7.98%(P＜0.05)、而密度增加了4.70%(P＜0.05).结果提示,添加中草药添加剂对肉质的改善的作用与横纹肌肌纤维直径的减少、肌间脂肪含量的增加有关。     

施钾和AM真菌对烤烟产量和品质的影响

通过盆栽和大田试验 ,研究了施钾和 AM真菌对烤烟产量、品质的影响。结果表明 ,在不同施钾水平下 ,接种 AM真菌对烟叶产量、品质具有明显的影响。接种 AM真菌具有提高宿主产量的功能 ,且菌根菌与施钾量二者之间存在最佳组合关系。施钾和 AM真菌对不同叶位烟叶干重的影响差异显著 (P<0 .0 1) ,但不同组合间差异较复杂 ,随叶位、施钾量不同而有区别。施钾量为 0 .75～ 1.12 5 g· kg- 1 时 (盆栽试验 ) ,接种 AM真菌的烤烟可获得较高产量和较佳品质的烟叶 ;施钾量为 6 7.5～ 10 1.2 5 kg/ hm2 时 (大田试验 ) ,接种 AM真菌的烤烟单株产量、每公顷产量最高 ,且超过了在 135 kg/ hm2 施钾水平下对照株的产量 ,还可以提高每公顷产值和中上等烟比例。     

兴义鸭的肉质性状测定及其相关性

为兴义鸭的选育及科学养殖提供理论依据,随机选取同批出雏、健康无病、体况相近的10周龄兴义鸭50只(公母各半),进行肉质性状测定及其相关性分析。结果表明:兴义鸭具备优良的肉品理化特性,保水性好,肌内脂肪含量和嫩度适中,脂肪酸以棕榈酸、硬脂酸、油酸和亚油酸为主,含量在95.23%左右,不饱和脂肪酸含量(57.075%)高于饱和脂肪酸(42.944%),且多不饱和脂肪酸较丰富。公母鸭脂肪酸含量无显著差异(P0.05);pH值与肉色呈显著正相关(P0.05),与失水率呈显著负相关(P0.05);不饱和脂肪酸间及其与SFA、EFA、UFA间多数呈极显著相关,C17:0与pH值呈显著负相关,C14:0、C16:1、C18:0、C18:1、C18:2、C20:3、C20:4、EFA与嫩度呈显著或极显著相关(P0.05或P0.01)。兴义鸭具有良好的肉质特性,是一个值得开发的优良地方鸭品种。     

温湿度对烤烟醇化过程中各化学成分的影响

从测定与烤烟醇化相关的指标物质入手,研究醇化库的温、湿度等条件对片烟醇化的影响。高温低湿(35℃70%)条件下既能保证烟叶含水量的安全,同时也促进了烟叶中物质的转化过程,加快了醇化进程,是本研究条件下最佳的醇化条件。     

鲜活农产品在连云港市的物流与营销

指出了人们对农产品的消费观念发生了深刻的变化，从消费者对农产品的需求及消费者购买行为两方面分析了连云港市的市场环境，并对鲜活农产品在连云港市的物流与营销进行了探讨。     

冬闲地种草养鹅模式下不同鹅品种生长性能、屠宰性能、肉品质的比较

为比较冬闲地种草养鹅模式下不同鹅品种的生长发育、屠宰性能和肉品质,以28日龄四川白鹅、浙东白鹅、扬州鹅和霍尔多巴吉鹅为研究对象,采取全程草地放牧加补饲方式,每组3个重复,每个重复10只,于70日龄开展屠宰测定和肉品质测定。结果显示:①在整个生长发育期间,四个品种鹅在生长发育前期增重较大,后期趋于缓慢。在生长发育前期(28~49日龄),扬州鹅的周增重均不同程度地高于四川白鹅和浙东白鹅,但在36~42日龄时扬州鹅的体增重低于霍尔多巴吉鹅;在生长发育后期(50~70日龄),扬州鹅的体增重均高于其他三个品种鹅。②扬州鹅的屠宰率高于其他三个品种的鹅;扬州鹅的腹脂率为1.39%,显著低于其他三个品种鹅。③扬州鹅不同部位肌肉中水分含量最低,胶原含量最高;扬州鹅的胸肌中蛋白质含量显著高于其他三个品种鹅。综上所述,扬州鹅可作为种草养鹅的理想品种,研究结果为种草养鹅模式下适宜品种的选择提供了理论依据。     

Are dual-purpose and male layer chickens more resilient against a low-protein-low-soybean diet than slow-growing broilers?

ABSTRACT

1. Although fattening dual-purpose types or male layer hybrid chickens appears more ethical than the common practice of culling day-old male layer chicks, the lower feed efficiency of these birds raises concerns. Replacing feed ingredients that compete with food production by those of lower value for human nutrition would be beneficial.

2. Lohmann Dual (LD), a modern dual-purpose type, Lohmann Brown (LB), a male layer hybrid, and Hubbard JA 957 (HU), a slow-growing broiler type, were fattened for nine weeks on two diets (control or ?20% crude protein; n = 6 × 12 birds). Growth, carcass and meat quality were analysed.

3. Growth performance of HU exceeded that of LD and especially of LB. The growth depression caused by the low-protein diet fed to LD (?7%) was only half of that found in HU (?13%). The LD fed the control diet had the same feed efficiency as the HU fed the low-protein diet. Even the LB had a lower performance and feed efficiency with the low-protein diet in growth. There was a gradient in carcass properties (weight, dressing percentage, breast meat yield, breast proportion and breast angle) from HU to LD to LB, with some additional adverse effects of the low-protein diet especially in HU. There were some breed differences in fatty acid profile in the intramuscular fat.

4. In conclusion, the dual-purpose type used complied with regulations for Swiss organic poultry systems in terms of growth rate and was found to respond less when fed a low-protein diet than the slow-growing broiler type. The LB males were inferior in all growth and carcass quality traits. Future studies need to determine the exact protein and amino acid requirements of dual-purpose and layer hybrid chickens and the economic feasibility of the systems, especially for organic farming.     

健康家兔肠道中乳酸菌的分离鉴定

本试验选用MRS、MRS+10%家兔硬粪浸出液和MRS+10%泡菜汁3种选择培养基,对健康家兔肠道的乳酸菌群分别进行需氧和厌氧培养,根据可培养细菌菌落特征、染色特性、显微镜形态观测,共分离出7株乳酸菌株,其中需氧菌2株,厌氧菌5株。结合生化试验初步鉴定,需氧菌株分别为乳酸乳球菌和短乳杆菌,厌氧菌株分别为嗜酸乳杆菌,嗜粪乳杆菌,肠乳杆菌,乳酸乳杆菌和弯曲乳杆菌。本实验为弄清健康家兔肠道的有益菌群,以便下一步制作更易于在畜禽的肠道中定植存活的复合动物微生态制剂做准备。     

Assessment of interactions between glutamine and glucose on meat quality,AMPK, and glutamine concentrations in pectoralis major meat of broilers under acute heat stress

The objective of this experiment was to evaluate the effects of dietary glutamine and glucose on pectoralis major meat quality in broilers under acute heat stress. Three hundred 35-day-old male broilers (Arbor Acres) were randomly divided into 5 groups. Broilers in the positive control group were kept in a thermoneutral environment (23 ± 1°C, RH 45%–55%) and fed a basic diet, whereas the experimental (2 × 2) group was exposed to acute heat stress (34 ± 1°C, RH 65%–75%) for 12 h and fed the basic diet that contained glutamine (0 and 10 g/kg) and glucose (0 and 10 g/kg). Compared with the positive control group, acute heat stress without glutamine and glucose supplementation increased (P < 0.05) drip loss, L* values, and AMPK concentrations, but it decreased (P < 0.05) water-holding capacity, moisture, pH, a* values, b* values, and glutamine concentrations in pectoralis major meat of chickens. However, dietary glutamine (10 g/kg) increased (P < 0.05) water-holding capacity, moisture, pH, a* values, b* values, and glutamine concentrations, while it decreased (P < 0.05) drip loss, L* values, and AMPK concentrations in heat-stressed chicken pectoralis major meat. Dietary glucose (10 g/kg) increased (P < 0.05) water-holding capacity, moisture, pH, and a* and b* values, while it decreased (P < 0.05) L* values and AMPK concentrations of pectoralis major meat in chickens exposed to acute high temperature. There were significant interactions between glutamine and glucose in the water-holding capacity, pH values, AMPK, and glutamine levels of pectoralis major meat in the heat-stressed chickens. The above results suggest that the addition of glutamine and glucose in the diet is necessary for broilers during acute heat stress condition.     

Fractionation of the reference inoculum of epizootic rabbit enteropathy in discontinuous sucrose gradient identifies aetiological agents in high density fractions

Epizootic rabbit enteropathy (ERE) is a major cause of economic loss in intensive rabbit production. Since its first recognition in 1997, much work has been done to determine the pathogenic mechanisms of the disease and to identify the aetiological agent(s). Unfortunately, the quest for aetiology has only met with limited success despite the ability to reproduce the syndrome by inoculation of intestinal contents from field cases. These intestinal inocula contain a huge number of microorganisms which could all be involved in the aetiology of ERE. To decrease the number of putative agents, the French reference inoculum TEC3 was fractionated on a discontinuous sucrose gradient so that seven fractions (supernatant, 10%, 20%, 30%, 40%, 50% and pellet) were obtained. Specific-pathogen-free rabbits were inoculated with three out of these seven fractions (supernatant, 30%, and pellet). The objectives were: (1) to characterise the seven fractions by bacteriological examination; (2) to verify whether the aetiological agent was present in the fractions by inoculation of rabbits; (3) to assign the aetiological agent of ERE to a morphological group of pathogens; (4) to identify a fraction which could replace the reference inoculum TEC3 in applications such as cell cultures or egg inoculation. The results strongly suggest that ERE is a bacterial disease and does not have a viral or parasitic aetiology.