1日龄火鸡新城疫免疫后外周血液的免疫学变化

应用ＮＤ来活苗与弱毒苗联合及单独弱毒苗对１日龄火鸡进行早期免疫，于第６０日进行ＮＤ强毒攻击。分别在第７、１４、２１、３５和日龄检测外周血液的免疫学变化。结果表明，１日龄火鸡疫苗接种后其外周血液中Ｔ细胞、Ｂ淋巴细胞和淋巴细胞数量、血清ＩｇＧ，ＩｇＭ，ＩｇＡ含量及ＨＩ抗体滴度均明显升高，可获得良好的免疫保护效应，其中活苗与死苗联合免疫组优于单独活苗免疫组。     

Breed and Management Interaction for Production and Reproduction in Swedish Dairy Cows

The effects of grazing during summer and possible interaction effects between breed and management system on milk production and postpartum reproductive performance were studied in 93 Swedish Red and White (SRB), Swedish Holstein (SLB) and Swedish Jersey (SJB) cows with 214 initiated lactations. The cows were divided into two groups: zero-grazing with tiestalls, or grazing during summer. Effects were studied by mixed-model analysis. The results indicated that grazing (rather than zero-grazing) can reduce the milk yield in the following lactation in SLB cows, whereas it had little effect on the production of SRB cows. Grazing SJB cows produced more milk, but with a significantly lower fat content. Grazing before or during the postpartum period stimulated reproductive performance, indicating a higher conception rate in all breeds and a 13-27-day shorter interval from calving to conception in the SRB and SLB cows, whereas in the limited number of SJB cows, the trend was the converse.     

三倍体毛白杨无性系人工林林地土壤养分消耗与林木生长研究

三倍体毛白杨因其速生、轮伐期短的特点,被广泛地用于造纸纸浆、胶合板材、纤维板材等工业,并在我国的山东、河北、辽宁、内蒙古等地开展了广泛的引种与规模化栽培[1].     

Effects of Rice Husk Powder on Performance,Body Size Traits,Internal Organs Development and Economic Benefit of Young Turkey

The purpose of this experiment was to study the effect of adding rice husk powder on the growth performance, body size traits, development of internal organs and economic benefits of young turkey. 180 young turkeys with similar body weight were selected and randomly divided into two groups, with each group having 5 replicates, each replicate of 10 birds. The control group was fed with basal diet, the experimental group was fed with basal diet added rice husk powder. The experiment lasted 8 weeks. The results showed that there was no significant difference in avarage daily feed intake (ADFI) between control group and experimental group (P>0.05).Compared with control group, the body weight and avarage daily weight gain (ADG) of the birds in experimental group increased extremely significantly (P<0.01), while the ratio of feed intake and daily weight gain (F/G) decreased extremely significantly (P<0.01); The heart weight of the birds tended to increase (P=0.09), whereas the proventriculus weight significantly increased (P<0.05), and the gizzard weight extremely significantly increased (P<0.01) in experimental group. There were no significant differences in body size traits, organ index, intestinal weight and length of the birds between control group and experimental group (P>0.05). The economic benefit of each bird in experimental group at 56 days of age was increased by 39.4% compared with control group (P<0.05). In summary, adding rice husk powder in young turkey's diets could improve the growth performance and the economic benefits of turkey.     

Effects of Metabolizable Energy and Amino Acid Levels on Turkey Performance from Hatch to Marketing

Two experiments were conducted with growing turkeys from hatch to market examining the performance at various dietary energy and amino acid (AA) levels as well as the relationship between energy and essential amino acids at these energy levels. The results of the first experiment indicated that increasing ME alone improved feed efficiency (FE); however, it did not affect BW in either toms or hens. In addition, increasing ME alone resulted in better regulation of caloric intake (CI) in toms than in hens. The caloric efficiency (CE) (BW/CI) improved with the higherenergy diets. In a second experiment both AA and ME levels were changed. Using 95% of NRC amino acid levels depressed performance, whereas turkeys receiving 105 and 110% of the recommended AA levels had improved BW and FE until 6 wk. From 7 to 19 wk, increasing dietary AA levels decreased feed intake (FI). Increasing both AA and ME together did not, in all cases, produce the same effect as altering their levels independently.     

Feeding time can alleviate negative effects of heat stress on performance,meat quality and health status of turkey

1. A total of 180 one-day-old turkeys were randomly assigned to 6 equal groups to investigate the effect of feeding time on growth performance, carcass characteristics, meat quality, leg problems and physiological responses of growing turkeys under the high temperature conditions of summer.

2. Birds of the first group were ad libitum fed and were considered as the controls (C). The second group (T1) was given 80% of diet in the morning and 20% of diet in the afternoon, the third group (T2) was given 60% of diet in the morning and 40% of diet in the afternoon, the fourth group (T3) was given 40% of diet in the morning and 60% of diet in the afternoon, the fifth group (T4) was given 20% of diet in the morning and 80% of diet in the afternoon and the sixth group (T5) was given 100% of diet in the afternoon.

3. Body weight, body weight gain and feed conversion ratio were improved with T2, T3, T4 and T5 in comparison to control or T1 under heat stress conditions. No significant impacts on carcass traits and meat quality due to changing the time of feeding were seen, except for tenderness and juiciness.

4. Feeding in the afternoon (100%) decreased body temperature and tonic immobility test score, which were positively related with the health condition of the birds.

5. The incidence of leg problems, plumage condition and breast blisters were not significantly different among the experimental groups.

6. It is concluded that feeding turkeys mainly or totally in the afternoon (T4 and T5, birds were fed with 80% or 100% of the diet in the afternoon) can be used as a strategy and a managerial tool for improving growth rate, feed utilisation, carcass and meat quality, as well as health status of growing turkeys reared under hot climate conditions.     

Modification of the lipid profile and antioxidant status of the blood plasma of turkey hens fed mixtures with raw or extruded linseed

The aim of the study was to determine the most beneficial proportion of raw linseed in complete feed mixtures for turkey hens on the basis of lipid and redox indicators in the blood. In experiment 1, the turkey hens received the complete mixture with 2%, 4% or 6% linseed. On the basis of the results obtained in experiment 1, we selected the most effective proportion of linseed, which was given to the birds in the group receiving a 4% linseed additive. In experiment 2, the birds were fed mixtures with a 4% addition of raw or extruded linseed. The use of 4% raw linseed was found to improve production effects (improvement of weight gain, and lower feed conversion ratios), while extruded linseed in the diet of turkey hens did not affect growth performance. The use of linseed (4% and 6%) as a feed component for turkey hens led to an increase in indicators of antioxidant potential, that is the total antioxidant potential of the plasma, vitamins E and C, bilirubin and creatinine. A benefit resulting from the use of linseed, particularly in the amounts of 2% and 4% was a marked improvement in lipid indicators in the blood. The reduced percentage of unsaturated fatty acids (n‐3) following the use of extruded linseed resulted in a decrease in lipid peroxidation (lower content of malondialdehyde, superoxide and vitamins C and E in the blood). The most effective dose and form of linseed in the diet of turkey hens is 4% raw linseed.     

Encephalomalacia Associated withVitamin E Deficiency in Commercially Raised Turkey

Thirteen of 64turkeys on a commercial turkey farm in Daqing exhibited neurological signs that included backward staggering,incoordination,generalized weakness,and sitting on their hocks with head retracted backward,Eight of the bires showing such signs were found dead.Two of these turkeys were necropsied,and no significant gross lesions were observed.Major histopathological lesions were found in the cerebellun and included multiple malacic foci in association tith neuropil rarefaction and astroglinosis within the white matter of folia.In addition,the hepatic vitamin Elevel of one turkey was determined at the High Pressure Liqid Chro-matography Laboratory in Life Science and Biotechnique Research Center of Northeast Agriculture Universi-ty.(NEAU-HPLCL)to be14.61μg/g dry weight.This vitaminh Elevel was in the lower percentile(35%)of 30turkey liver samples examined at NEAU-HPLCL.A diagnosis of vitaminE-associated encephalomalacia was made bassed on chlinical signs,gross and histological lesinons,and liver vitamin Elevels.     

The development of injurious pecking in a commercial turkey facility

Injurious pecking is considered a major economic concern and affects all sectors of commercial poultry production. Though extensive research has been performed examining feather pecking in layer chickens, little information exists regarding feather or head pecking behavior in domestic turkey flocks, and less still in commercial settings. The objective of the present field study was to examine the development of injurious feather and head pecking in tom turkeys raised in 2 different commercial environments. At a commercial facility, 49,332 beak-conditioned tom turkeys were placed in 8 barns (5,000–7,500 turkeys/barn) and studied through 16 wk of age. Approximately half were housed in control barns in March 2010; these barns were environmentally controlled (artificial light and tunnel ventilation) in both rearing and growing, with a density of 0.16 m²/bird for rearing through 4.5 wk and 0.39 m²/bird for growing through 16 wk. The remaining turkeys were housed in curtain-sided barns in April 2010; the 4 rearing barns were environmentally controlled with a density of 0.10 m²/bird, whereas the 4 growing barns had natural light and ventilation and a density of 0.36 to 0.38 m²/bird through 16 wk. Two barns from each growing environment were provided with multicolored plastic balls as enrichment. Each housing and enrichment combination had 2 replicate barns. Behavior, weights, and feather condition were assessed every 3 wk. Mortalities and culls were recorded as they occurred. Turkeys in curtain-sided barns had worse feather condition and more culls and mortalities with severe pecking injuries compared with those in control barns. In both environments, severe and gentle pecking was observed throughout production, and the majority of culls and mortalities had severe pecking injuries. More controlled studies are needed to parse the causal factors of injurious pecking in toms.