Effects of an induced molt using cassava meal on body weight loss, blood physiology, ovarian regression, and postmolt egg production in late-phase laying hens
| Autor: | N. Sopa, N. Yu-nun, K. Poonpan, J. Aungsakul, Nirat Gongruttananun, P. Kochagate |
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| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
medicine.medical_specialty Manihot Oviposition Ovary Molting Hematocrit Biology Body weight Feed conversion ratio Egg Shell 03 medical and health sciences Animal science Internal medicine Weight Loss medicine Animals Animal Husbandry photoperiodism Meal medicine.diagnostic_test 0402 animal and dairy science 04 agricultural and veterinary sciences General Medicine Blood physiology Animal Feed 040201 dairy & animal science Diet 030104 developmental biology Endocrinology medicine.anatomical_structure Oviduct Animal Nutritional Physiological Phenomena Female Animal Science and Zoology Chickens |
| Zdroj: | Poultry Science. 96:1925-1933 |
| ISSN: | 0032-5791 |
| DOI: | 10.3382/ps/pew457 |
| Popis: | This study was conducted to determine the effect of an induced molt using cassava meal on body weight, blood physiology, ovary, and postmolt performance in late-phase (74 wk old) HN Brown laying hens. Hens were randomly assigned to 3 treatments of 90 birds each: 1) Controls withno induced molt (CONT); 2) molted by full feeding with cassava meal for 3 wk (FP3); and 3) molted by full feeding with cassava meal for 4 wk (FP4). Groups 2 and 3 were fed a pullet developer diet for 3 wk following treatment. During the molt period, the birds were exposed to an 8L:16D photoperiod and had access to drinking water at all times. Thereafter, all hens were fed a layer diet (17%CP), and exposed to a 16L:8D photoperiod, and production performance was measured for 16 wk. The molt treatments resulted in total cessation of egg production within 2 wk following feeding the molt diet. BW loss of birds in the FP4 treatment was approximately 30.13%, which was significantly higher than those in the FP3 treatment (25.23%). At the termination of feeding the molt diet, an increase in hematocrit values was observed for the FP3 and FP4 treatments compared to the CONT treatment. Conversely, lower values of serum estradiol, progesterone, ionized Ca and phosphorus concentrations were found for the 2 molted treatments. Ovary weight, number of follicles, and oviduct weight and length of the FP3 and FP4 treatments were diminished as compared to the CONT treatment. No consistent differences were observed between the molted treatments. Significant (P0.05) improvements in postmolt feed efficiency, egg production, Haugh units, shell weight, shell thickness, shell breaking strength, and mortality rate were observed for the FP4 treatment. An improvement in those performances, except for feed efficiency and egg production, was also found for the FP3 treatment. It was concluded that feeding the cassava molt diet for 4 wk could induce molt in laying hens effectively, and produce optimum postmolt productive performance. |
| Databáze: | OpenAIRE |
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