兵团农机产业化的若干思考

农机产业化是社会分工细化、生产专业化深化的必然产物，其实质是传统农业转变为现代产业的过程。日前，兵团农机产业化进程中存在着一些问题。为此，结合兵团实际，提出了推进农机产业化发展的基本思路。     

Behaviour in one fast-growing and one slower-growing broiler (Gallus gallus domesticus) hybrid fed a high- or low-protein diet during a 10-week rearing period

This study compared behavioural time budgets, presence of comfort behaviours and social behaviours in two different broiler genotypes (the fast-growing Ross 308 (R) and the slower-growing Rowan Ranger (RR)) fed organic diets with high (17.0% crude protein (CP)) or low (14.5% CP) protein content during a 10-week rearing period. 429-day-old chicks (218 R and 211 RR, respectively) were included in the study and behaviour was recorded at 2, 6 and 9 weeks of age. The results showed no effect of diet treatments but that R broilers were less active and sat, ate and drank more frequently than RR broilers, which stood and perched more frequently. However, both hybrids showed decreasing activity and foraging behaviour with increasing age, while time spent eating and sleeping was approximately similar over the entire rearing period.     

On farm observations to increase genetic gain in breeding schemes for village poultry production – A simulation study

To improve genetic gain of breeding programs for village poultry production, breeding schemes with observations obtained in village production systems using individual (VIO) and group recording (VGO) were examined under different levels of genotype-by-environment-interactions (GxE). GxE was modeled by varying the correlation between traits measured in the breeding station and village environments for bodyweight (r_{g_BW}) and egg production (r_{g_EP}). Relative and absolute genetic gains obtained from VIO and VGO were used for comparison between the schemes. Results showed that village observations significantly improved genetic gains compared to the scheme without birds tested in the village. The improvement was only slightly larger with individual observations than with group observations. Higher r_{g_BW} and r_{g_EP} led to lower relative genetic gain, but a higher absolute gain of VIO and VGO. It is recommended to apply a breeding scheme using group recording of village performance when strong GxE in breeding for village poultry is expected.     

Evaluation of smallholder pig production systems in North Vietnam: Pig production management and pig performances

This study investigated the productive adaptability of pig breeds under different smallholder production conditions in Vietnam, comparing an indigenous with a Vietnamese improved breed. Fieldwork was conducted in four villages with different remoteness in North Vietnam from 2001 to 2002, in 64 households keeping the improved Mong Cai or indigenous Ban as sow breeds and progeny for fattening. Four visits per farm yielded 234 structured interviews. Reproductive performances were derived from 135 litters. Individual weights of pigs (n = 755) were obtained. Data were analysed by regression, linear and generalised linear, especially loglinear models.

Two distinct pig production systems were identified, that differed in remoteness, market access, resource availability, distribution of pig breeds and pig production intensity. Higher performances of 1.4 and 1.5 litters year^− 1, 8.4 and 8.4 piglets weaned litter^− 1, 66.6 and 93.0 kg piglets weaned sow^− 1 year^− 1, and 136 and 177 g day^− 1 ADG were found in two villages near town with semi-intensive production conditions and a high rate of improved Mong Cai sows and MC and LW × MC offspring in the observed population. Lower performances of 1.1 and 1.1 litters year^− 1, 4.6 and 5.5 piglets weaned litter^− 1, 20.5 and 30.9 kg piglets weaned sow^− 1 year^− 1, and 66 and 85 g day^− 1 ADG were observed in parallel to higher incidences of indigenous Ban pigs away from town under extensive conditions. Total live weight offtake per household per year was higher near town and in one village distant to town. MC and LW × MC remained even under demand-driven conditions below the performance potential reported for improved genotypes. Under resource-driven conditions with a saving-oriented production pattern, the higher-yielding but more demanding Mong Cai might not be an efficient production alternative as a further performance reduction can be assumed. A considerable live weight output was observed under resource-driven conditions and with a higher percentage of crossbred LW × Ban offspring in the population, possibly representing a promising production alternative. Factors influencing the performance expression of pigs, and the suitability of different methods for the assessment of performance parameters on-farm are discussed.     

Maternal behaviour and performance in first-parity outdoor sows

When sows and their litters are kept outdoors, much of the responsibility for the litter is shifted from the herdsman to the sow compared to when the sows are kept indoors. Therefore, the maternal ability, including maternal behaviour, is believed to be important in outdoor piglet production. The aim of this study was to describe maternal traits in conventionally bred first-parity sows kept outdoors. Nursing behaviour, sow activity, sow body reserves, litter size and piglet growth were studied in 40 first-parity sows during a seven week long lactation. The sows were kept in groups outdoors. Sow activity (lying down or active) and nursing behaviour (nursing frequency, nursing duration and nursing terminator) were recorded on videotapes at four days post partum (pp) and directly observed at four and six weeks pp. Cross suckling was observed at four and six weeks pp. Sows were weighed and measured for backfat depth five days before farrowing, two weeks pp and at weaning seven weeks pp. Piglets were weighed at four days pp, at two weeks pp and at weaning. We concluded that sow nursing behaviour and activity are individual characteristics repeatable within sows' late lactation. Less active sows are more available for suckling. Light and thin sows have an earlier and more progressed weaning process than heavier, fatter sows. A significant positive relation was found between sow appetite in early lactation and piglet growth until weaning. Sow nursing behaviour is not important for piglet growth when sows and piglets are held in groups, piglets have access to sow feed and piglets are weaned as late as at seven weeks of age.     

Growth and development of Lilium longiflorum ‘Nellie White’ during bulb production under controlled environments : II. Effects of shifting day/night temperature regimes on scale bulblets

One-year old scale bulblets of Lilium longiflorum Thunb. ‘Nellie White’ (Easter lily) were grown for 107 days during growth period 1 (GP-1) in six growth chambers under constant day/night temperature regimes of 30/26, 26/22, 22/18, 18/14, 14/10 and 10/6 °C. Subsequently, half of the plants in each temperature regime were transferred to 18/14 °C and the other half continued at the six constant temperature regimes. Both groups of plants were grown for an additional 89 days in growth period 2 (GP-2). Continuous temperatures of 26/22, 26/22–22/18 and 26/22–18/14 °C produced the greatest increase in basal bulb fresh weight (the main planted bulb), basal bulb circumference and stem bulb fresh weight, respectively. However, shifting these optimal temperatures to 18/14 °C during GP-2 resulted in a lower increase in basal bulb fresh weight and circumference. The optimum range for stem bulb production was expanded to 30/26–14/10 °C by shifting to 18/14 °C. The greatest increase for basal root growth occurred at 14/10–10/6 °C and for stem root growth at 14/10 °C. The temperature shift did not affect either root type. Maximum increase for stem length was at 26/22 and 22/18 °C and for stem plus leaf weight at 14/10 °C under constant temperature regimes. Transferring the plants from 10/6 to 18/14 °C resulted in the greatest increase in stem length and from 10/6 and 14/10 to 18/14 °C in the greatest increase in stem plus leaf weight. The greatest increase in the number of leaves occurred at 26/22 and 10/6 °C, but this growth parameter was unaffected by shifting to 18/14 °C, indicating that leaf number was determined in GP-1. Bulbils developed only when bulbs at high GP-1 temperature regimes (30/26 and 26/22 °C) were transferred to 18/14 °C during GP-2. Lower temperatures tended to favor an increase in flower bud production under continuous temperature regimes, while shifting to 18/14 °C increased flower bud production after initially high and low temperatures. Meristem abortion was greatest at 30/26 °C followed by 26/22 °C, but was not affected by temperature shifts in GP- 2. Thus, it is concluded that the abortion was induced or initiated during GP-1.     

不同温度和温湿度组合对米蛾的影响

不同温度处理对米蛾有不同饲养效应。试验结果表明:以26℃饲养米蛾效果最好,幼虫存活率,平均蛹重,平均蛹长,成蛾率,产卵量,繁殖倍数均居首位。25℃和28℃对米蛾的生长发育和生殖产卵均有不利影响,21℃不适合米蛾生长发育的需要。在26℃条件下,采用人工加湿的办法,使相对湿度保持在84％左右,对米蛾生长发育和繁殖均有明显促进作用,各项生物学指标分别达到:幼虫存活率95.8％,平均蛹重31.54毫克.平均蛹长9.64毫米;成蛾率55％,单雌产卵量370粒,群体繁殖倍数达59倍。降低湿度,不但延缓米蛾的发育进度,还直接降低了米蛾的产卵量和繁殖倍数。     

家禽起源与驯化研究进展

随着全基因组扫描技术的突破及学科交叉互动,近年来家禽起源、驯化研究取得了一些重要进展。家禽为人类提供肉、蛋及羽绒,也用于宗教礼仪及文化生活。在人类文明进程中驯养家禽占据不可或缺的地位。分子生物学技术及考古学研究表明,家禽驯化是一个复杂而漫长过程,家禽适应人类改变了形态、行为及生理,人类因家禽出现改变了饮食结构及行为方式。家禽来源于野生物种,不同的家禽在不同地点由不同族群独立驯化而成,驯化过程伴随其他物种基因渗入。揭示家禽起源不仅是一个科学问题,对保护家禽遗传多样性及遗传育种都有重要意义,未来全基因组扫描及花粉考古有望成为家禽驯化研究热点。     

面向循环经济的畜禽养殖发展思路

本文阐述了循环经济的特征及其运行模式，分析了传统畜禽养殖业的污染现状及其原因，讨论了面向循环经济的畜禽养殖业应遵循的三大原则，即减量化、再利用和资源化，对畜禽养殖技术、废物利用技术进行了探讨，提出畜禽养殖业应该走循环经济的发展模式，通过研制生态饲料及废物综合利用，达到畜禽粪便的减量化、资源化和无害化。     

不同培养基继代培养蜡蚧轮枝菌对产孢量和烟粉虱毒力的影响

为了探究不同培养基继代培养的蜡蚧轮枝菌对烟粉虱的作用效果,通过继代培养方法测定JMC-01、JMC-02菌株的产孢量、对烟粉虱的毒力及其几丁质酶活性。结果表明,JMC-01、JMC-02菌株在添加蝉蜕和烟粉虱的PDA培养基中连续培养5代的产孢量、对烟粉虱的毒力、几丁质酶活性均高于无添加的PDA培养基,且JMC-01菌株的各项参数均高于JMC-02菌株。JMC-01菌株在添加蝉蜕的PDA培养基中T_1和T_3代的产孢量最大,均为1.279×10~7个/mL,T_3代对烟粉虱的毒力最大,为88.33%,T_5代的几丁质酶活最高,为0.268 3 U/mL;在添加烟粉虱的PDA培养基中,JMC-01菌株的最大产孢量、对烟粉虱的最高毒力和最高几丁质酶活分别出现在S_2、S_4和S_5代,分别为1.270×10~7个/mL、88.33%和0.325 4 U/mL。回归分析结果显示,JMC-01、JMC-02菌株几丁质酶活性与烟粉虱校正死亡率呈显著的正相关,且拟合优度较好。本试验表明JMC-01、JMC-02菌株均对烟粉虱具有较强的毒力,添加蝉蜕和烟粉虱的培养基可以维持菌株生长特性、增加产孢量、延缓菌株退化、增强菌株的几丁质酶活性,为烟粉虱的生物防治提供了新的菌种资源。