Imprinting Preference Test
Imprinting procedure had a greater impact on both Imprinting Preference and Social Preference Tests in terms of approaching imprinting stimuli. As expected, latency was highly consistent between individuals, as well as after replicating each test, imprinted chicks took less time to move towards imprinted stimuli than the control chicks. This is also in line with previous studies where they stated that chicks make an attachment to visually moving objects and show predisposed to reach moving objects after being exposed to stimuli for more than 30 minutes (Bateson, 1966; Martinho, 2016; Kacelnik, 2016) since our imprinting preocess was in 90 minutes.
Another reason of the reduction in latency could be the presence of two different stimuli in imprinting procedure (e.g. tidbitting sound and visual stuffed hen). Previous study claimed tthe combination of several stimuli have a stronger effect on learning than being presented alone.
Social Preference Test
The imprinted chicks displayed shorter latency in the replication compared to those in Imprinting Preferece Test. Morever, the latency to approach deacreased for the control chicks.
In the hen zone, imprinted chicks were more tend to stay here in both first trial of the experiment and its replication, compared to the time chicks spent in Experiment 1. It shows that chicks could clearly discriminate imprinting stimuli as soon as they come across novel stimuli. The reason would be the reaction of fear or coming across an undefined object for the first time (Bateson, 1976). A previous study which focused on newly hatched chicks had not been exposed to any visual stimuli prior to testing in darkness, shows a correlation with our findings. In that situation, it showed that chicks had spontaneous preferences to the face-like configurations (Di Giorgio, 2017).
Social Isolation Test
The results showed that there is no strong correlation between treatments; I only saw slight difference in peeping frequency, with control chicks, having more distress calling. we calculated peeping frequency to observe the imprinting effects in the absence of companion or imprinting stimuli, we observed that distress calling was not the only reaction when they are in fear-related situation in this test. Besides peeping, flying over to the box or freezing are also important response to be considered, which is categorized depressive-like syndrom ( Katz, 1981).
Another fragment in the results that imprinting procedure had no substantial effect on distress call could be the changes in main factors during the entire study such as age. Kaufman (1961) found in his study distress call in naive chicks decaresed with age. So, it is possible that the deacrese in peeps is not related with being imprinted but age.
•The imprinting procedure was successful in domesticated chicks to shorten the chicks’ approaching time to imprinting stimuli and distinguish novel objects.
•The imprinting procedure was not enough for identifying the frequency of distress calling, however, it had an impact on the decrease in the rate of peeps calls.
•Imprinting can be a way to improve chicks’ welfare by developing more artificially simulated features to decrease the possible implications for the chicks caused by the absence of a mother-offspring bond.