Dietary supplementation with diatomaceous earth was proposed in this study in order to evaluate its effect on the concentration of parasites, egg production and egg quality of free-range organic laying hens. 440 Novogen Brown hens of 54 weeks of age were split in two groups of 220 hens each and fed a basal organic diet with (intervention group) and without (control group) supplementation of diatomaceous earth for five weeks. Faecal egg counts were performed in faecal samples once a week using the McMaster and Modified Stoll methods. External and internal egg quality tests were performed in eggs sampled on weeks one and five of the trial. Four DNA extraction methods for faeces were applied and compared, and DNA was tested for the presence of Eimeria species parasites by PCR; Eimeria acervulina was detected and quantified by qPCR. Dietary treatment did not have a significant effect on the concentration of parasites, but seemed to lower the parasite counts of Ascaridia galli and Heterakis gallinarum. Intervention daily egg production and laying index were increased, and even if they laid good quality eggs these failed to prove better quality eggshells or lower number of broken eggs. Further studies may want to consider a dietary intervention with diatomaceous earth in a flock of younger (pullets) or oder hens and increasing the length of time of the trial.
|Date of Award||2018|
|Supervisor||Justin Pachebat (Supervisor)|
Use of Diatomaceous Earth as a dietary supplement in organic laying hen production
Tello Velamazan, J. (Author). 2018
Student thesis: Master's Thesis › Master of Philosophy