Maternal Diet Influences Offspring Feeding Behavior and Fearfulness in the Precocial Chicken

Abstract

BackgroundIn chicken, oils in the maternal diet confer a specific scent to the yolk. Embryos are known to perceive and memorize chemosensory signals of the surrounding environment; however, the potential impact of the maternal diet has not previously been investigated. In the present study, we hypothesized that chicken embryos memorize the chemical signals of the maternal diet and that this perceptual learning may orient subsequent feeding behavior of the hatchlings.Methodology/Principal FindingsLaying hens were fed standard food enriched with 2% menhaden oil (MH group) or 2% soybean oil (controls). The scent of menhaden was significantly more detected in MH egg yolks than in control yolks by a human panel. We analyzed the development and behavior of offspring towards different types of food, bearing or not bearing the menhaden scent. When chicks were exposed to a 3-min choice test between the familiar food bearing the menhaden scent and the familiar food without menhaden, no effect of treatment was observed. In a 3-min choice test with unfamiliar food (mashed cereals) MH chicks showed a clear positive orientation toward the unfamiliar food bearing the menhaden scent. By contrast, control chicks showed a preference for the non-odorized unfamiliar food. MH chicks expressed higher emotional reactivity level than control chicks as expressed by food neophobia and longer immobility in a restraint test.Conclusion/SignificanceChicks exposed in ovo to menhaden oil via the maternal diet preferentially oriented their feeding behavior towards food containing menhaden oil, but only when the food was unfamiliar. We propose that oil in the maternal diet engenders maternal effects and contributes to the development of behavioral phenotype in the offspring. In ovo chemosensory learning may have evolved to prepare precocial offspring for their environment. This suggests a common principle of embryonic chemosensory learning across vertebrate taxa.

Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks

“…On the other hand, control chicks ingested preferentially the odorized unfamiliar food rather than the nonodorized unfamiliar food. The same result was obtained in our previous study in which chicks were exposed to the menhaden scent via maternal diet (Aigueperse et al, ). It is possible that the in ovo chemosensory experience in combination with the posthatch chemosensory experience coact in the construction of feeding preferences.…”

“…We used menhaden oil because previous studies indicated that the presence of menhaden in the diet of hens naturally confers a “fishy smell” into the eggs (Sirri, Meluzzi, Immerseel, Nys, & Bain, ). In addition, we demonstrated that chicken embryos exposed to menhaden oil via maternal diet were able to learn this odor (Aigueperse et al, ).…”

“…Analysis of Feeding Preferences. All of the tests used and the protocol were previously described by Bertin et al (2012) and Aigueperse et al (2013). Chicks become extremely distressed when isolated, and therefore we tested chicks in pairs from the same exposure conditions during choice tests.…”

“…Exposure to chemosensory stimuli at the end of incubation (when embryos breathe air inside the egg) exhibited more pronounced effects than in the middle of incubation (embryos are surrounded by amniotic fluid) (Bertin, Calandreau, Arnould, & Lévy, ) but olfactory learning can take place before the breathing stage (Bertin et al, ; Hagelin et al, ). Moreover, we demonstrated that chicks exposed in ovo to fish oil (menhaden) via maternal diet preferentially oriented their feeding behavior toward food containing menhaden oil when the food was unfamiliar (Aigueperse, Calandreau, & Bertin, ).…”

Lipids in maternal diet influence yolk hormone levels and post‐hatch neophobia in the domestic chick

“…In domestic hens, we previously showed that adding fish oil to the maternal diet induced food neophobia in the offspring (Aigueperse, Calandreau, & Bertin, 2013). As fish oil is particularly rich in n-3 poly-unsaturated fatty acids (PUFA), this result suggested that PUFA in the maternal diet may directly affect the development of behavior in the offspring.…”