Effects Of Training Methods And Environmental Factors On Domestic Chickens' Cognitive Behavior

Ethology is a subject that studies the interaction between animals and their environment.With the development of animal behavior,more and more researchers were concerned about animal experience and animal cognition was derived.Animals with cognitive abilities can experience pleasure and pain.Nowadays the poor environment has caused abnormal behavior.We assessed the cognitive ability by object-choice tasks.The purpose of this paper was to investigate the performance of object-choice tasks by the domestic chickens in three different stages:3-day-old,15-day-old and 150-day-old,and then effects of gesture cues and environmental factors on the chickens were discussed.Three parts as follow:1 Effects of training methods and environmental enrichments on domestic chickens' cognitionThe experiment of object-choice tasks was divided into four stages:training(0-1 day old),the first test period(2-3 days old),rearing period(4-15 days old),and the second test period(16-18 days old).Total 156 new-born chickens were divided into two parts:the manual training group with 81 birds and the watching-video group with 75 birds.For the human-given training group,an experimenter showed the food to the chicken,and then placed the food in one bowl randomly.The experimenter kept motionless while the bird looked for the food in 30 s.For the watching-video group,the chickens were demanded to watch the video that the birds found the food successfully in the experimenter-given training group.The first test was performed after the training.Five gesture cues were used in the test periods,Pointing(P),Gaze(G),Pointing and Gaze(P+G),Body Location(BL)and None(N).After the first test,the chickens were randomly reared in two different environments:the enriched environment and the non-enriched environment.Therefore,four groups in each above group were presented,training and enriched environment,training and non-enriched environment,non-training and enriched environment,and non-training and non-enriched environment.The procedure in the second test was as the same as the first test.The results showed that chickens' performance was better(P<0.05)and less time spent in P+G trials(P<0.05)than those in other trials in 3-day-old stage,either human-given or watching-video group.Compared to the human-given training group,the chickens performed the tasks better and spent less time in the watching-video group.During the second experiment,P+G cues brought the highest success rate and the least time spent(P<0.05)in 8 groups.There was no effect by environmental factors in the human-given training group,but both the training and environmental factors affected the chickens performing the object-choice tasks.In summary,all cues could help the chickens to finish the object-choice tasks and found the hidden food,especially P+G and P cues.Meanwhile,the early training experience could affect the chickens' task performance.2 Effects of different training methods on the cognition of domestic chickensThirty domestic chickens were divided randomly into three groups:training(T),observation(O)and interaction(I),and ten birds were in each group.In the T group,an experimenter showed the chickens their favorite food and required the birds to find the hidden food in 30 s.Chickens in the O group were required to watch the successful training video of the T group and chickens in the I group were required watched the training period of the T group.Gesture cues included:Pointing(P),Gaze(G),Pointing+Gaze(P+G),Body Location(BL),Pointing,Gaze and Body Orientation(P+G+BO)and None(N).Object-choice tasks were used.The results showed that all chickens had the best performance while the experimenter gave the P+G cue.In the T group,the success rate was higher than 80%with the P+G cue and 50%with the other cues.There were no significant difference in the recognition rate by all cues between the O and I groups.In summary,adult chickens made good performances with the P+G and P cues,which could showed that the chickens were sensitive to hand gestures.Training could improve the cognitive abilities of chickens.3 Effects of predator risks on chickens' food choice and behavioral time budgetsEight chickens,four males and four females,were divided into four groups and rice and wheat with the similar color and size were provided.Dog' s bark recording was used to simulate the predator risk and to investigate effects of the bark on the food choosing and behavior performance by chickens.Results showed that the predator risk reduced significantly the consumption of rice and both the time and frequency of feeding were significantly reduced(P<0.05).Meanwhile,the predation risk affected the behavioral time budget,especially moving,vigilance and resting.While the risk presented,male chickens increased their resting and females decreased their moving and foraging and increased their vigilance.In summary,the predation risk affected the behaviors of domestic chickens and the consumption of their preferred food decreased.