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121.
We tested the hypothesis that poultry by-product meal would produce a thermogenic response (an increased requirement for oxygen) resulting in an increased incidence of pulmonary hypertension with right ventricular failure and ascites in commercial broiler chickens.

Four treatment groups, each with three replicates of 40 chicks, were fed a commercial broiler starter to day 21, grower to day 35, and the following experimental diets after day 35: group 1, commercial chicken broiler finisher; group 2, commercial chicken broiler finisher with poultry by-product meal added to replace part of the soyabean meal; group 3, commercial chicken broiler finisher with poultry fat added to replace the animal-vegetable (AV) fat; group 4, commercial chicken broiler finisher with both poultry by-product meal and poultry fat added to replace soyabean meal and AV fat. On day 35, pen temperature was reduced to 15°C, and on day 42 to 12°C.

Mortality from ascites between days 35 and 56 was 11(9%) in group 2, 5(4%) in group 4 and 3(2.5%) in groups 1 and 3 The incidence of pulmonary hypertension, as measured by an increased right ventricle: total ventricle (RV:TV) ratio (RV:TV > 0.249) at processing on day 57, was higher in the groups receiving poultry by-product and poultry fat: 27(22.5%) in group 2, 26(21.7%) in group 3, and 20(16.7%) in group 4 compared to that of the controls 12(10%).

  相似文献   
122.
Caprine arthritis-encephalitis-virus (CAEV) was isolated from the carpal joint of an Anglo-Nubian yearling goat with chronic progressive pneumonia and subclinical carpal arthritis. Anti-CAEV antibody was detected in this goat and in nine of 69 goat sera tested from two herds.  相似文献   
123.
  目的  生物资源调查是保护区进行管理和保护的基础,对九龙山国家级自然保护区进行鸟类资源调查分析,可提供目前鸟类群落状况,为鸟类的保护和恢复提供科学依据。  方法  通过整合历史文献、进行鸟类专项调查和红外相机调查,分析九龙山国家级自然保护区的鸟类群落。  结果  共记录鸟类165种,隶属15目49科,主要为留鸟(56.36%)。群落优势种为灰眶雀鹛Alcippe morrisonia和红头长尾山雀Aegithalos concinnus。需重点保护的鸟类共有37种,其中,国家Ⅰ级重点保护鸟类2种(白颈长尾雉Syrmaticus ellioti和黄腹角雉Tragopan caboti);国家Ⅱ级重点保护鸟类26种;列入IUCN物种红色名录的10种,列入中国脊椎动物红色名录的18种。鸟类地理区系组成上兼具古北界和东洋界成分,但以东洋界(89种,53.94%)为主;121种繁殖鸟中,以东洋界种最多(69.42%);古北界种在旅鸟和冬候鸟中占比最多(分别为84.62%和100.00%)。  结论  九龙山国家级自然保护区鸟类资源丰富,占浙江省鸟类物种数的30.00%以上;区系组成以东洋界为主,且有向古北界过渡特征。表4参13  相似文献   
124.
分别以栽培和野生条件下的九龙山榧(Torreya jiulongshanensis)(雌、雄株)及同属广布种——榧树(T.grandis)为材料,比较了其叶片叶绿素荧光参数对光强的响应,以期为九龙山榧种质资源保育提供科学依据。结果表明,栽培条件下,九龙山榧雌株幼苗叶片的光系统I最大荧光值整体高于榧树及九龙山榧的雄株;九龙山榧雌、雄株幼苗的光饱和点也较高,分别为788.581和550.640μmol/(m2·s),所对应的最大电子传递速率也较高,分别为40.690和39.546μmol/(m2·s)。同样,在野外条件下,九龙山榧雌、雄株的光饱和点也均显著高于榧树,分别为1165.361和1416.817μmol/(m2·s),光系统II最大电子传递速率也以九龙山榧雌株为最高,其值为80.322μmol/(m2·s)。由此可见,九龙山榧为阳生树种,且与榧树相比具有更强的光合潜力。  相似文献   
125.
This study investigated consumer behavior towards meat across Asia and Pacific-Rim countries. Mail surveys were undertaken in 1994 and 1995. Data was obtained from 6197 households in Japan, the USA (mainland and Japanese–Americans in Hawaii), Australia, Thailand, Korea, Taiwan and China. The data were mainly analyzed using cluster analysis to determine the distance between each country and to classify countries into groups. Japanese respondents purchased beef more frequently than respondents from other countries. The average amount purchased on each occasion was far more for Australian respondents than for respondents from other countries, while Japanese purchased far less. Respondents in Japan, Korea, China and Australia thought beef was the most expensive meat, whereas lamb was thought to be the most expensive in the remaining countries. Chinese respondents indicated the highest consciousness of price indexes. The level of uneasiness about eating meat indicated by Asian respondents was relatively strong compared with respondents in Hawaii, the USA and Australia. Average ratings (semantic differential scale) on plans for future meat consumption were higher for beef than for other meats in Korea and China, whereas chicken was rated higher in the other countries. From the dendrogram, surveyed countries were classified into three groups: Japan, Taiwan and Korea; Thailand and China; and the USA, Japanese–Americans and Australia. Among them, the first and second clusters merged into a larger cluster, the 'Asian' group.  相似文献   
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