Abstract
Earlier studies on breeding birds indicated no effect of dietary energy-content on feed intake. This observation is contradictory to results for other animals and/or poultry where feed intake decreases with an increase in dietary energy level. Literature revealed that a lack of certain nutrients may cause animals to consume more feed than necessary to satisfy their nutrient requirements for these limiting nutrients. In this study eight diet groups were evaluated. A standard commercial diet plus one of the following supplements: (i) Standard diet without a vitamin and mineral premix pack (control diet), (ii) with a normal premix pack, (iii) with normal vitamin and 2 x trace elements (M x 2), (iv) with normal trace elements and 2 x vitamins, (v) with a normal premix pack and limestone added as calcium source; (vi) with a normal premix pack and monocalcium phosphate added as phosphorus source, (vii) with a normal premix pack and soybean oilcake added as crude protein source, (viii) with a normal premix pack and linseed added as a fatty acid source. Significant differences were recorded in the quantity of feed ingested by birds between the diet with surplus minerals (M x 2) (Group 3) (2.3 ± 0.3 kg/bird/day), the diet with no vitamins and minerals added (Group 1) (2.7 ± 0.3 kg/bird/day) and the diet with added fatty acids in the form of linseed (Group 5) (2.9 ± 0.5 kg/bird/day). This indicates the possibility that ostriches may adjust feed intake to satisfy their mineral requirements. No statistically significant relationship was found between the thickness and strength of the shell. Significant differences in shell strength (mean value of 154.7, 109.9, 140.4, 142.7, 153.0, 143.4, 138.4 and 151.1 N/cm2, respectively) were found between all treatments, but no specific pattern could be identified. Results further revealed no effect of dietary treatment on egg production, dead-in-shell eggs (DIS), infertile eggs or chick production. Further experiments that include certain dietary treatments during the five months rest period are currently being done to quantify the effect of the addition of minerals and vitamins during this period on the production of breeding ostriches.Keywords: Eggshell strength; feed intake, minerals, vitamins
Highlights
Cooper et al (2004) stated that most ostrich performance problems relating to fertility can be traced back to an inadequate breeder diet
The higher feed intake of the birds fed the control diet than those fed the diet with the additional minerals (M x 2) may indicate that the birds in the first treatment group consumed feed to satisfy their need for minerals
If the additional minerals compensate for a higher feed intake, it may imply higher profitability levels for the ostrich producer
Summary
Cooper et al (2004) stated that most ostrich performance problems relating to fertility can be traced back to an inadequate breeder diet. 75% of a producer’s running costs can generally be attributed to that of the breeder birds’ nutrition (Brand et al, 2002b; Aganga et al, 2003; Kritzinger, 2011). Correct formulation of these diets, to ensure that adequate amounts of vitamins and trace elements are supplied, will prevent feed wastage and increase profitability. Earlier studies on breeding ostriches have indicated no effect of dietary energy content on feed intake. This observation is contradictory to results for other animals and/or poultry (March et al, 1984). Supplementation of feed generally occurs in the form of added premix packages which contain vitamins, minerals and other trace elements
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
