Effects of in ovo feeding with glycerol for broilers

    loading  Checking for direct PDF access through Ovid


Embryo development in birds is limited by the nutrient content present in the egg, especially in the final third of incubation (Gonçalves et al., 2013). Furthermore, it is known that weight is directly related to post‐hatch survival of birds, batch homogeneity and performance in the production phase (Decuypere and Bruggeman, 2007). This fact becomes even more important when the genetic potential of birds of zootechnical interest, such as broiler chickens, is considered. Moreover, the embryo starts to perform anaerobic catabolism of glucose in the period preceding hatching (Oliveira et al., 2008), especially because the energy demand for pipping the shell is large and the oxygen tension is low (Moran, 2007). As the concentration of carbohydrate in the egg is considered low compared with that of other nutrients, <1% of the total (Sugino et al., 1997), blood glucose and embryonic glycogen reserves are maintained by gluconeogenesis from amino acids, glycerol and other gluconeogenic compounds (Oliveira et al., 2008; Sunny and Bequette, 2010), thus reducing the availability of these nutrients for muscle growth. Therefore, the injection of gluconeogenic compounds directly into the amnion could enhance bird development at the end of the incubation stage and shortly after hatching.
Another problem that has been observed in current broiler strains is the physiological immaturity of the avian digestive tract in the early days post‐hatching (Uni et al., 2000). Besides limiting the absorption of nutrients required for growth during the first days after hatching, the presence of undigested material in the gastrointestinal tract favours colonization by pathogens (Lan et al., 2005), increasing the incidence of diarrhoea and further compromising animal performance. One way to stimulate early development of the gastrointestinal tract is to ensure the presence of highly digestible nutrients before and immediately after hatching (Noy and Uni, 2010). This has been achieved with the use of pre‐housing nutrition (Careghi et al., 2005) or in ovo feeding (Tako et al., 2004; Grodzik et al., 2013; Yair et al., 2015).
Glycerol, or propane‐1,2,3‐triol, is an organic alcohol compound that is liquid at room temperature (25 °C), hygroscopic, odourless, viscous and has a sweet taste (IUPAC, 1993). Studies evaluating the addition of this compound to the diet of broiler chickens have confirmed an increase in bird performance and carcass yield (Silva et al., 2012). Because glycerol is the main precursor of gluconeogenesis and glycogen synthesis (Sunny and Bequette, 2011), it is assumed that the in ovo feeding of this compound may favour glycogen stores, spare amino acids for muscle growth and stimulate intestinal maturity in broiler chickens. Therefore, the objective of this study was to evaluate the effect of in ovo feeding, which is defined by administration of nutrients in the amnion for the purpose to feed the embryo, with glycerol on the development of broiler chicks after hatching.
    loading  Loading Related Articles