Enhancing duck well-being through early-age stimulation, human-animal interaction, and probiotic supplementation

Intensive modern poultry production exposes birds to a multitude of stressors, posing substantial challenges to their welfare. However, there is still a lack of research on the effects of positive human-animal interaction, early-life stress, and a probioticsupplemented diet on stress resilience, fearfulness, and growth performance in ducks undergoing processes like catching, crating, and transportation. This thesis aims to fill this gap. Hence, the thesis's first objective was to investigate the effects of positive human contact on fear and physiological stress in Pekin ducks (Anas platyrhynchos domesticus) subjected to crating and transport. This study exposed the ducks to human contact across various age groups. At D 42, serum levels of corticosterone (CORT), heat shock protein 70 (HSP70), and tonic immobility (TI) tests were analysed following 3 hours of crating or 3 hours of transport stresses. The study reveals that ducks that received human contact from D1 to D42 and from D1 to D21 had significantly higher levels of HSP70 expression than the no-contact group, but human contact had no effect on growth performance. Human contact and stressors significantly affected the TI duration. The second objective aimed to determine the effects of early-life stress on growth performance, fear, and physiological stress responses, as well as gut microflora composition in both Pekin and Muscovy (Cairina moschata) ducks subjected to transportation stress at market age. The ducks were stressed at D3 to D14 by keeping them in a climate chamber set at 24°C±1 and hearing 100 dB of noise (construction and road traffic noises) for three hours every day, and at D42, the ducks underwent three hours of transportation stress. Blood analyses for CORT and HSP70 were done at D14 and D42. The RT-PCR for the gut microbiota count and TI tests were conducted at D42. The results showed that subjecting Pekin ducks to early-life stress can alleviate the stress associated with transportation at market age by significantly changing the CORT and HSP70 levels in Pekin ducks but not in Muscovy ducks. The TI test demonstrated a significant breed difference, with Muscovy ducks exhibiting a longer TI duration and more attempts compared to Pekin ducks. The Pekin ducks showed significantly higher weight gains and feed intake compared to Muscovy ducks. Earlylife stress is also beneficial in maintaining the gut population of Lactobacillus spp. following transportation. For the third and fourth objectives, the experiments were conducted on Pekin ducks that were fed with probiotic-supplemented feed containing CLOSTAT® (Bacillus subtilis) at a concentration of 1 g/kg on D1 to D21. Blood tests for heterophil-tolymphocyte ratio (HLR), serum biochemistry such as creatine kinase (CK), total protein (TP), triglycerides (TG), glucose (GLU), total cholesterol (CHOL), and lactate (LACT), stress hormonal (CORT and HSP70), TI, and exploratory behaviour tests were determined at D21 after 4 hours of crating stress. The findings revealed that the dietary intervention did not exert a significant impact on growth performance. Despite this, the probiotic-added diet significantly reduced the levels of CORT, HSP70, HLR, TG, and CK in ducks compared to those fed the control diet. The exploratory and fear-related behaviour tests also showed that B. subtilis supplementation significantly decreased TI duration, lowered TI attempts, and increased their exploratory activity in a new environment. In summary, the experiments indicate that positive human contact, early life stress, and dietary probiotic supplementation collectively have a significant impact on stress resilience in ducks, but they did not affect growth performance.

Text 122970 edited.pdf Download (1MB) Official URL or Download Paper: https://ethesis.upm.edu.my/id/eprint/18690

Actions (login required)

View Item