Effect of size on spawning time in the lesser sandeel Ammodytes marinus.

Ovarian development was examined in relation to size and temperature in late pre-spawning Ammodytes marinus over 5 years. Oocyte diameter was positively related to length indicating that larger females spawned earlier. Age and temperature, whilst accounting for the effect of length, were not found to affect oocyte development, although the thermal range examined was only 1·3° C.

Physiological and behavioral responses of poultry exposed to gas-filled high expansion foam.

Disease control measures require poultry to be killed on farms to minimize the risk of disease being transmitted to other poultry and, in some cases, to protect public health. We assessed the welfare implications for poultry of the use of high-expansion gas-filled foam as a potentially humane, emergency killing method. In laboratory trials, broiler chickens, adult laying hens, ducks, and turkeys were exposed to air-, N2-, or CO2-filled high expansion foam (expansion ratio 300:1) under standardized conditions.

Physiological responses of laying hens during whole-house killing with carbon dioxide.

1. Poultry on farms are sometimes required to be killed in an emergency, such as during a disease epidemic, yet none of the available methods are ideal. Whole-house carbon dioxide (CO(2)) administration has practical advantages, but gives rise to welfare concerns.

Sedimentation patterns caused by scallop dredging in a physically dynamic environment.

Scallop dredging grounds in the Firth of Lorn, western Scotland, are juxtaposed with rocky reef habitats raising concerns that reef communities may be impacted by sediment disturbed by nearby scallop dredging. A particle-tracking model of sediment transport and settling is applied at two scales. In the near-field, a suspension of typical sand/gravel-dominated bed sediment is subjected to a steady current across the dredge track.

Pain perception, aversion and fear in fish.

There is now compelling evidence that teleost fish possess similar nociceptive processing systems to those found in terrestrial vertebrates. Noxious stimulation of these nociceptors--specialised pain receptors -in the skin around the snout of fish generates neural activity that can be electrophysiologically recorded, and induces a number of behavioural and physiological changes. To determine whether changes in behaviour are more than simple responses to the noxious stimulation it is necessary to demonstrate that higher order cognitive processes such as mental state or 'affective state' are involved.