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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Effect of Duration of Feed Restriction, Prebreeder Protein Content, and Nesting Material on Growth and Reproductive Performance of Commercial Large White Turkey Breeder Hens

Klein-Hessling, Hermann III 26 April 1998 (has links)
Large White turkey breeder hens were used to examine the effect of duration of feed restriction, prebreeder protein content, and nesting material on subsequent growth and reproductive performance. Day old poults were raised following standard commercial practices with feed and water for ad libitum consumption until 6 wk of age (WOA). At this time, hens were equally divided among six grower feeding regimens. The treatments were as follows: a) a control group fed standard commercial diets for ad libitum consumption (CON); b) a second control group like (a) but fed plain white oats from 19 through 26 wk (OATS). In contrast, the 4 remaining treatment groups were feed restricted beginning at 6 WOA to achieve body weights 45% less than the full-fed CON at 16 WOA. Birds were kept at this level of restriction until either 17.0 (R17.0), 18.3 (R18.3), 19.6 (R19.6), or 20.9 (R20.9) WOA. Thereafter, feed allowance was gradually increased to achieve a predetermined minimum target BW of 10.8 kg at photostimulation. An additional prebreeder protein treatment was superimposed from 27 to 31 WOA. Treatments reduced BW but none of the four quantitatively restricted groups achieved the target BW of 10.8 kg at photostimulation. Feed restriction reduced feed consumption and improved feed conversion. There were no differences in flock uniformity, sexual maturity, mortality, body composition at photostimulation, and total egg production. The R18.3 treatment achieved the highest peak production. The quantitative restriction treatments exhibited low laying persistency. There were no differences in number of large yellow follicles, egg weight, fertility, or hatchability, but poult weight was reduced in the R18.3 treatment. Dietary protein influenced the proportions of multiple follicle sets and percentage misshaped eggs.Three nesting materials were compared and were as follows: 1) all nests filled with shavings (S), 2) all nests filled with paper chips (P), and 3) two nests filled with shavings and two nests with paper chips (S/P). There were significant differences in percentage floor and broken eggs. Nesting materials did not affect total egg production, fertility, or hatchability. The data suggest, if restriction is too severe and is continued too near to the time of conventional photostimulation, BW recovery and egg production will be depressed. Oat feeding was the easiest treatment to implement and resulted in equivalent reproductive performance. Dietary protein content may affect proportions of multiple follicle sets. Turkey breeder hens can and do distinguish between nesting materials and this may affect floor laying. Combinations of various types of nesting materials within the same breeder unit should be avoided. (Key words: turkey breeder hens, feed restriction, prebreeder protein, egg production, body composition, nesting material) / Ph. D.

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