| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Oregon State University, Corvallis, 97331-6702
Abstract
An experiment utilizing 391 preweaning and 187 postweaning litter records from 145 does was conducted for 12 mo to determine the effect of dietary crude protein level on performance of commercial New Zealand White rabbits. Does and their litters were fed alfalfabased pelleted diets containing either 17.5, 19 or 20.5% crude protein (CP). In a separate experiment, the 17.5 and 20.5% CP diets were fed during lactation to 10 does to determine nitrogen (N) digestibility and retention. Body weights of does fed 17.5% CP were lower (P<.01) than for the other treatments after 21 and 28 d of lactation. No differences (P>.10) were observed for doe weight at kindling, percentage fertility, litter size, preweaning litter mortality, 1- to 21-d consumption, preweaning feed efficiency and 28- to 56-d average daily consumption, average daily gain and average weight. Total born tended to be higher (P=.07) on higher protein levels but percentage born alive was greatest (P<.01) on the 17.5% CP diet. Does fed 19% CP tended to have a greater number of parities (P=.06). Other significant differences observed for preweaning litter traits were between 17.5 and 19% CP groups. Does fed 19% CP had heavier litters at birth (P<.01), at 21 d (P=.05) and 28 d (P=.06) and had greater 1- to 21-d litter gains and 21- to 28-d consumption (P=.05) than those fed 17.5% CP. For postweaning performance, feed efficiency values were lowest and mortality was highest for litters fed 20.5% CP. When litters were switched to different diets after weaning, mortality tended to be higher (P=.07) for animals that were fed 20.5% CP before weaning. The month of experiment effect did not influence any of the characters studied (P>.05). Parity number was important for percentage fertility, percentage born alive, litter birth weight and doe weight at 21 and 28 d (P<.05). Does at first parity showed the poorest performance for all traits (except percentage fertility). Fertility fluctuated throughout the first four parities and then steadily declined. Does fed 20.5% CP had greater apparent dry matter and acid detergent fiber digestibilities and N intakes (P<.05) and retained 90% more N during lactation (P=.22) than does fed 17.5% CP. Milk production and CP digestibility did not differ between the two diets tested. Results indicate that 17.5% CP is not optimal for the lactating commercial rabbit and 20.5% CP provides no advantage over 19% CP. A general purpose diet for maximum production of both lactating does and growing fryers should contain approximately 19% CP.
1 Oregon Agr. Exp. Sta. Tech. Paper No. 7287.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
