Weight Changes in Quail Eggs During Incubation
Commercially, Quails are mostly raised for their meat and eggs. The eggs are tastier, low in calories and are good sources of essential vitamins, minerals and amino acid, thereby making it a preferred egg compared to other poultry eggs. Chick weight at hatch positively impacted on subsequent productivity indices of Quails thereby making it a primary index for the future performance traits of the bird. Differences in chick weight at hatch have been largely influenced by the pre-hatch egg weight and weight loss associated with incubation. Chick weight is primarily determined by initial egg weight and is secondarily determined by weight loss during incubation, shell and residue weight, strain, incubation time and conditions, breeder age and chick sex. This study aims at investigating some egg measures and its influence on chick weight at hatch with a view to statistically predict its chick weight. The eggs used in this study were sourced from a semi-intensively managed poultry farm in Jos, Plateau State in the Savannah region of Nigeria. A total of 987 hatching Quail eggs were collected and appropriately labeled for identification purposes and set for incubation. Out of the total eggs set, 606 eggs were hatched and were used for the analyses. Egg weight and egg shell weight were measured with a sensitive (0.00g) digital scale, while egg length and width were measured with a sensitive (0.00 mm) digital Vernier caliper. Other measures included both the vertical and horizontal circumference of the eggs using a flex graduated tape, 14th day incubation weight of egg and chick weight at hatch. Indices such as shape index, egg density, egg surface area, egg volume and incubation weight difference were computed. With the exception of shell thickness and shape index, all other variables were highly significantly (P<0.01) impacted on chick weight and were used to model. The statistical model for predicting chick weight at hatch using the eleven variables that significantly influenced chick weight at hatch is given by: Y = β0 + β1X1 + β2X2 + β3X3 + β4X4 + β5X5 + β6X6 + β7X7 + β8X8 + β9X9 + β10X10 + β11X11. The model accounted for 31 percent of the variability in chick weight. The study revealed that egg weight, density, volume and incubation weight loss were the largest influence on chick weight.
Keywords: Quail Eggs, Incubation, Chick Weight