 ผลงานตีพิมพ์ในวารสารวิชาการThe effects of a short-term molt method using cassava meal, broken rice, or corn on ovarian regression, bone integrity, and postmolt egg production and quality in older (95 week) laying hensผู้แต่ง: Dr.Nirat Gongruttananun, Associate Professor ,  Guntapa, P., Saengkudrua, K., วารสาร:  
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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Red Light Illumination on Productivity, Fertility, Hatchability and Energy Effi ciency of Thai Indigenous Hens) ผู้เขียน:ดร.นิรัตน์ กองรัตนานันท์, รองศาสตราจารย์, Pannapat Guntapa สื่อสิ่งพิมพ์:pdf AbstractThis study was conducted to determine the effects of red light exposure on the productivity, fertility and hatching characteristics in Thai native hens (Gallus domesticus). A total of 120 birds aged 18 wk were housed in an open-sided shed and exposed to one of the following lighting treatments: 1) natural daylight supplemented with fl uorescent light (Control), 2) natural daylight supplemented with red light (NR) and 3) red light as the sole light source (R). The red light was produced by light- emitting diodes. All treatments were provided with a daily light:dark photoperiod of 16:8 hr over a 28-week egg-laying period, and there were four replicate pens of 10 hens for each treatment. Photostimulation of the light sources was initiated at age 18 wk and any subsequent effects on the live performance and reproductive traits were observed during the experimental period. Feed and water were available at all times. Body weights, feed consumption and mortality rates were similar among the treatment groups. The age at fi rst egg of the NR birds (130.7 d) was comparable to that of the R birds (129.2 d) which was signifi cantly less than that of the control hens (134.7 d). During the fi rst week of the laying period, R hens produced more eggs than did hens in the control treatment (P < 0.05), whereas the NR birds exhibited an intermediate value between those groups. At 2 wk after photostimulation, the serum estradiol concentration was signifi cantly higher for hens in the R treatment compared to those of the control and NR treatments. The hematocrit values of the birds in the R treatment tended to be lower than those of the other two treatments in some periods of the study. During the lighting period from weeks 6 to 8, a signifi cantly improved feed conversion ratio was observed in the R and NR treatments compared to that of the control treatment. No signifi cant differences in egg weight, egg and eggshell quality or any parameters of hatching occurred between the R and control groups. The weights of the ovary, pituitary gland, spleen and the abdominal fat were similar for all light treatments. It was concluded that photostimulation by red light resulted in an acceleration of sexual development in Thai native hens compared to hens exposed to full-spectrum lighting; however, live performance, egg production, egg and eggshell quality, and fertility were not affected whatever the light treatment. The light-emitting diode lighting regimens could be benefi cial for energy conservation and the reduction of rearing costs in laying hens. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Utilization of Different Basal Diets for Molt Induction in a Strain of Commercial Laying Hens) ผู้เขียน:ดร.นิรัตน์ กองรัตนานันท์, รองศาสตราจารย์, ดร.ชัยวัฒน์ บุญแก้ววรรณ, ผู้ช่วยศาสตราจารย์ , Viriya Lungyai, Panaput Guntapa สื่อสิ่งพิมพ์:pdf AbstractThe objective of the study was to evaluate a nonfasting method for induced molting of laying hens by using different basal diets. An experiment was conducted using 300 H&N Brown hens (aged 95 wk ) randomly assigned to one of five treatment groups: group 1 (NC), which served as the non-molt control group, was provided with a layer ration and exposed to a 16:8 daylight:dark (L:D) photoperiod daily throughout the study, whereas groups 2 (BR), 3 (RB), 4 (C) and 5 (CM) were subjected to an induced molting program. Hens in the BR group were fully fed with a broken rice molt diet, whereas for 14 days, hens in the RB, C and CM groups received rice bran, corn mash and cassava mash molt diets, respectively. During the 2 wk molt period, all birds were exposed to an 8L:16D photoperiod and had access to drinking water at all times. Following the molting period, all hens were fed the layer ration and provided with 16 h of light per day, and production performance was measured for 20 wk. The CM treatment resulted in total cessation of egg production within 7 d. Egg production of hens in the BR, RB and C treatments all decreased to 3.7, 2.6 and 8.7%, respectively. Bodyweight loss ranged from 6.0 to 22.0%, with the highest value for the CM treatment. At the end of the molt period, no significant differences in the mortality rate, the ratio of heterophil to lymphocyte numbers and plasma cortisol concentrations were found among the experimental bird groups. No consistent differences were observed among the molt treatments throughout the 20 wk postmolt period for egg production, egg weight or egg quality. However, the peak of egg production of hens in the CM treatment reached a level of 70% of hen-day egg production, which was higher than those of the other treatments. In addition, during the early phase of the postmolt period, egg production and albumen quality of the CM treatment were significantly improved as compared to those of the control group. At week 2 of the postmolt period, the egg shell thickness of the CM treatment was significantly lower than that of the control group. The results indicated that feeding the cassava molt diet is an effective non-feed removal method for molting laying hens. However, the technique needs to be adjusted to improve egg production and egg shell quality. Keywords: molting, laying hen, cassava, egg quality, cortisol |
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