Comparing fostering success between wild-caught and game farm bred captive red-legged partridges (Alectoris rufa, L.)

Occurrence of veterinary pharmaceuticals in golden eagle nestlings: Unnoticed scavenging on livestock carcasses and other potential exposure routes

Wildlife exposure to pharmaceuticals can occur through contaminated water, and through the excreta and carcasses of medicated livestock, with potential for bioaccumulation and transfer through food webs. We evaluated whether nestling exposure to pharmaceuticals can occur from food delivered to nests in the golden eagle (Aquila chrysaetos), a top predator and facultative scavenger. Despite the fact that diet analysis suggests an apparently low dependence on livestock carcasses reduced to two piglets remains (1.5% of food remains, n=134), a high proportion of nestlings (71%, n=7) showed fluoroquinolone residues in plasma, mostly enrofloxacin, which is exclusively used in veterinary treatments. The occurrence and concentration (54.5±6.6μg·L^-1) of fluoroquinolones in plasma was similar to those found in the nestlings of three vulture species largely dependent on livestock carcasses obtained at supplementary feeding stations, which are managed for the conservation of their populations. Although the number of analysed eaglets is comparatively small, the fact that enrofloxacin was found in all nests sampled in three breeding seasons suggest an exposure to the drugs similar to that of vultures. An underestimation of the role of carrion, especially from small piglets whose consumption may have gone unnoticed, and the predation of semi-domestic prey and generalist prey exploiting carcasses of medicated livestock, can contribute to explaining the unexpectedly high occurrence of these drugs in eaglets.

A comparison of fat-soluble antioxidants in wild and farm-reared chukar partridges (Alectoris chukar)

This study assessed differences in antioxidant (carotenoid, retinol, retinol-ester, vitamin E and coenzyme Q₁₀) composition of egg yolk and tissue in chukar partridges (Alectoris chukar) newly hatched from eggs of birds maintained in captivity on commercial maize-soybean based diets and birds from the wild whose diet was obtained from the natural environment. All eggs were incubated in a commercial hatchery. Day-old chicks from both groups were sacrificed and dissected for antioxidant analysis. Fat soluble antioxidant concentrations of egg yolk and tissues were determined by HPLC. Total carotenoids, retinol, alpha-tocopherol, and total vitamin E concentration of wild egg yolks were significantly higher compared to yolks from farm-reared birds (p<0.05). However, gamma tocopherol, and coenzyme Q₁₀ were not significantly different in the yolks of either wild or farmed birds (p>0.05). The concentration of total carotenoids in all tissues of wild chukar one-day old partridges was significantly higher than in farmed one-day old chukar partridge tissues (p<0.05). Alpha tocopherol, free-retinol, retinol-esters and total vitamin A were significantly higher in most tissues of wild chukar when compared to farmed chicks (p<0.05). Coenzyme Q₁₀ concentrations of heart, kidney and brain tissues of farm-reared chukar day old chicks were significantly higher than tissues from wild birds, although leg and breast tissues of wild chicks were significantly higher than in farmed birds (p<0.05). These findings suggest that maternal access to antioxidants in the diet of farmed chukar partridges could positively influence fat soluble antioxidant concentrations in the egg yolk and tissues of day old chicks.

Gender-related amino acid intake of adult wild Red-legged Partridge (Alectoris rufa)

The Red-legged Partridge (Alectoris rufa) is under an enormous hunting pressure. It is bred intensively in game farms. The hunting season is during the non-reproductive resting period when partridges are at maintenance conditions. There is a lack of information about the amino acid (AA) composition of the natural diet of the adult birds in their habitat or differences in dietary AA composition related to gender. The objective of this work was to establish a first approach to the AA composition of the natural diet of adult wild Red-legged Partridge. Food content in crops and gizzards of female and male birds hunted in the same hunting season and area was analysed for AA composition. Females food had higher concentrations of individual essential AA (EAA) and non-essential AA (NEAA) than males. There are important differences in the concentration of AA in the natural diet of wild females and males. It may be advisable to use diets differing in the proportion of individual AA in the game farms during the non-reproductive resting period.

Anti-predator behaviour of adult red-legged partridge (Alectoris rufa) tutors improves the defensive responses of farm-reared broods

The aim of this work was to improve natural anti-predator behaviour of farm-reared gamebirds. We evaluated the anti-predator behaviour of reared red-legged partridge Alectoris rufa chicks kept in brooder houses in large groups (>350 chicks), trained and not trained by parent red-legged partridges acting as experienced tutors. The experiment consisted of two conditioned tests (a raptor model and a human) and two control tests, which were conducted during three consecutive phases of life (1-4, 15-17 and 30-32 d after hatching). The motor anti-predator behaviour, its duration, the intensity of response in chicks and alarm calls elicited by adults were recorded. Tutors elicited aerial alarm calls (76% of tests) and showed prolonged crouching (59% of tests) in response to the raptor model whereas uttering the ground alarm call (73% of tests) and showing vigilance behaviour (78% of tests) was the main pattern during the human test. Trained and not trained chicks showed similar motor behaviour in response to the raptor model (crouching) and the human test (escaping), but frequency of strong responses (all chicks responding) from chicks trained with tutors was double that of chicks trained without them, and chicks trained with tutors showed a higher frequency of long responses (41-60 s). This study indicates that anti-predator training programmes before release may improve behaviour of farm-reared partridges which may confer benefits to survival of birds.