Using a fixed-speed test, burst swimming performance was found to vary among nine populations of emergent sockeye salmon Oncorhynchus nerka fry reared in a common-garden environment. No consistent relationship was, however, detected between difficulty of fry migration (upstream v. downstream) to rearing areas and total burst swimming duration or bursting rate.

The aim of the research was to evaluate the influence of sex, breeding group, litter size and age of lambs when placed in lambing pens for their growth rate during rearing. The average daily gain of lambs was evaluated based on their weighing data each week after their placement into lambing pens. Lambs of Improved Valachian, Tsigai and Lacaune breed (n=26) had been gradually integrated to the ...

This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare...

Three-hour milk production measurements determined by machine milking at 3-d intervals throughout a 63-d lactation period were used to describe lactation curves for crossbred ewes lambing at 1 and 2 yr of age and rearing single and twin lambs. Age of ewe, type of rearing, and day of lactation affected (P < 0.05) milk production. Over the 63-d lactation, average daily milk production was 2.56 an...

Contains: 7 figures and 4 tables; All text is double-spaced, 26 pages. Abstract The amount of visual information an animal can extract from its environment is ultimately limited by the signaling performance of its photoreceptors. To maximize their performance photoreceptors must be able to accommodate large changes in input caused by the dynamic properties of the visual environment and the anim...

The nutritional status of food plants and altitudes play pivotal role in successful rearing of Indian tropical tasar silk worm Antheraea mylitta Drury both in commercial and seed crops. The pupa is the most crucial stage of its life cycle for the adult life and race continuation as well as for exploiting its genetic potency and dynamics to our best advantages. In the present investigation an ex...

Transgenerational maternal effects on performance (rm) after host transfer were evaluated in the generalist aphid Myzus persicae s.s., and in its subspecies specialized on tobacco, M. persicae nicotianae Blackman. We tested whether the performance of these taxa, when reared separately on optimal and suboptimal hosts (as sources of different maternal background) and then transferred to optimal h...

The amount of visual information an animal can extract from its environment is ultimately limited by the signaling performance of its photoreceptors. To maximize their performance, photoreceptors must be able to accommodate large changes in input caused by the dynamic properties of the visual environment and the animal's own behavior. This is likely to require a range of adaptation mechanisms o...

Considering different fertility traits 411 cows from 73 farms used for economic analyses. From these, 202 lactating cows were selected for evaluating the fertility status. Pre-tested data sheets were used to record the socioeconomic status of the farms including their assets, cost and return and productive and reproductive performance of the dairy cows. Targets were set considering the situatio...