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2. Neither the position of the birds on the lorry, nor their sex, nor the ambient temperature nor the identity of the experimeter exerted any significant effects on tonic immobility reactions.
3. Although the longest and shortest immobility responses followed transportation in the fixed crates and metal modules respectively, system comparisons may be confounded by variations in the birds’ genetic and/or experiential backgrounds.
4. Both journey duration and waiting time before transport bore an unambiguous and positive linear relationship with mean TI duration. The duration of transit was the major factor determining fear levels following both commercial and simulated journeys. 相似文献
2. The feeding of whole oats halted egg production in 5.7 ±0.22 d and the duration of the pause was 8.3 ±0.78 d.
3. The induction of a pause improved the subsequent rate of egg production, egg output, efficiency of food utilisation, albumen quality, egg specific gravity and shell colour. It also increased food intake and body weight gain but neither egg weight nor the rate of mortality were affected.
4. Neither supplementation of the diet with iron nor its source had any significant effect on laying performance, egg quality or shell colour. 相似文献
2. No differences in growth or efficiency of food utilisation were apparent on feeding the more saturated fat. Skin tearing was slightly reduced and carcase quality slightly improved on feeding the more saturated fat for 28 d.
3. Decreases in linoleic acid content in intra‐abdominal fat were apparent after 14 d feeding the diet containing saturated fat. These decreases were greater after feeding the saturated fat for 28 d. 相似文献
2. The application and success of AI programmes in commercial broiler breeder operations are largely dependent on efficient cage management (nutrition, lighting, environment, health programmes) of both males and females.
3. Artificial insemination will remain a viable alternative for the broiler industry, which competes within the economic constraints of least‐cost production. 相似文献
2. TAM administration at the embryonic stage, but not at the day of hatching, reduced adiposity in females but not in males, at 8 to 9 weeks of age. This reduction in adiposity in females minimised or even alleviated the excess of fat in females compared to males. 相似文献
2. One proposed method of ensuring proportionality among nutrients involves numerous calculations during matrix construction, hampering matrix interpretation and revision.
3. An alternative, more convenient approach is presented and discussed. 相似文献