Dave Waddington

A bovine whole-genome radiation hybrid panel and outline map

A 3000-rad radiation hybrid panel was constructed for cattle and used to build outline RH maps for all 29 autosomes and the X and Y chromosomes. These outline maps contain about 1200 markers, most of which are anonymous microsatellite loci. Comparisons between the RH chromosome maps, other published RH maps, and linkage maps allow regions of chromosomes that are poorly mapped or that have sparse marker coverage to be identified. In some cases, mapping ambiguities can be resolved. The RH maps presented here are the starting point for mapping additional loci, in particular genes and ESTs that will allow detailed comparative maps between cattle and other species to be constructed. Radiation hybrid cell panels allow high-density genetic maps to be constructed, with the advantage over linkage mapping that markers do not need to be polymorphic. A large quantity of DNA has been prepared from the cells forming the RH panel reported here and is publicly available for mapping large numbers of loci.

Influence of motivational state on choice of food or a dustbathing/foraging substrate by domestic hens

Domestic hens were trained to run a Y-maze and make an association between differently coloured doorways and access to food pellets or sand. The hens were tested for their choice of doorway when the goals were not visible from the choice point and when they were food or sand deprived. Hens made the choice appropriate to their deprivation state (correct choice) significantly more often for food than sand and were faster at choosing and entering the goal box when food deprived. In a follow up experiment, the goals were visible from the choice point. Again the hens chose correctly significantly more often when food than sand deprived and made the choice and entered the goal box faster when food deprived. Thus, failure to choose sand in the first experiment was not due to an inability to learn the association, but appears to result from a strong motivation to feed in the Y-maze, even when not food deprived, and a weak motivation to dustbathe or forage, even when sand deprived.

Previous experience with different floors influences choice of peat in a Y-maze by domestic fowl

Chicks of two strains of domestic fowl were reared on either floors of wire (wire reared) or concrete covered with wood shavings with access to peat (litter reared). At 13 weeks of age, the birds were given a choice of wire or peat in a Y-maze. The wire-reared birds tended to choose wire and the litter-reared birds tended to choose peat.

Can domestic fowl (Gallus gallus domesticus) anticipate a period of food deprivation

Abstract Forty ISA Brown pullets were individually housed and fed in an environment designed to eliminate circadian cues. On Days 17–47, half of the birds were presented with a cue (a coloured card) during the final hour of food availability, prior to a period of deprivation of either 8 or 12 h. Food intakes were recorded to determine whether the cued birds showed anticipatory crop-filling. There was no indication that the birds learned that the cue predicted a period without food, as their intake did not increase during the final hour of feeding. These results are discussed in relation to the cognitive abilities of fowl and the implications for their welfare.

Measuring the motivation of domestic fowl in response to a positive and a negative reinforcer

Ten ISA Brown hens were trained to run an alleyway of 14.4 m in length to obtain a food reward. Each hen was deprived of food for each of 0, 6, 12 and 18 h on four occasions and the times taken to run the alleyway were recorded. The three deprivation periods resulted in greater speeds than the control (P<0.001), but there was no difference between the speeds for the deprivations. In a second experiment, 15 ISA Brown hens were trained to run the same alleyway for a food reward and then allocated to three groups which received differing numbers of exposures to a feather duster (negative reinforcement) on entry to the goal box. The three groups (0, 1 and 2) were given zero, four or eight exposures, respectively, during a 32 day period. The speeds of Groups 0 and 1 increased linearly during the experiment, but the slopes were not statistically distinguishable. The speeds of Group 2 showed a curvilinear pattern, with no overall change between the start and end of the experiment, but with a decrease in speeds during the middle part of the experiment.