Biscuit residue in the nutrition of laying hens: effects on animal health, performance and egg quality

ABSTRACT

Background: Corn and soybean meal are common ingredients used in poultry feed in order to supply the demand forenergy and protein, respectively. Also, these ingredients directly influence the final price of the diets, and consequently,the final cost of production. A major problem is associated to the oscillation of these grains in some months of the year.Therefore, there is a need to search for nutritionally and economically viable alternatives to mitigate this problem. The aimwas to evaluate whether the addition of biscuit residue could partially replace the use of corn in the feed of laying hens inorder to obtain economic viability without impairment on production, egg quality and animal health.Materials, Methods & Results: The experiment was completely randomized and each repetition was considered one experimental unity. One hundred Hy-line brown 48 week-old chickens were allocated in cages and divided into five groupswith four repetitions each, allocating five animals per cage. The group T0 was composed by animals that received thebasal diet, i.e. without biscuit residue. The other groups were composed by increasing levels of biscuit residue to substitutecorn i.e., group T7 (7% of biscuit residue), T14 (14% of biscuit residue), T21 (21% of biscuit residue) and T28 (28% ofbiscuit residue). Productive performance of the animals, egg quality, as well as analysis of blood parameters related tolipid metabolism, carbohydrates and proteins of birds were measured at the beginning of the experiment (day 0) and atthe end of each cycle (days 21, 42 and 63 of experiment). Among the performance variables, only feed conversion wasaltered by biscuit residue, i.e., the feed conversion was lower in the groups that received the residue when compared tothe control. The replacement of corn by biscuit residue did not affect laying rate (P > 0.05). Regarding egg quality, a less...