Muhammad Imtiaz Azam (2013-VA-566)

Productive And Reproductive Performance Of The Parents And The Growth Performance Of Subsequent Progeny As Influenced By Molting In Japanese Quails - 2015. - 67p.;

Japanese quail is a member of order Galliformes, family Phasianidae, genus Coturnix and specie Japonica. Scientific name of Japanese quail is Coturnix coturnix japonica (Mizutani, 2003). Japanese quail attained significance as agriculture specie due to its unique flavor of eggs and meat hence got importance as a food animal (Kayang et al. 2004). Egg production is important in south East Asia whereas meat is an important product in Europe (Baumgartner, 1994: Minvielle, 1998). Female quail starts laying at the age of 6 weeks and constantly produces eggs for at least one year. Quail is efficient converter of feed, with each egg a female deposits an edible package of 8 percent of her own body weight as compared to 3 percent in case of chicken (Martin et al. 1998).
Molting in avian species is the periodic shedding and replacement of feathers as well as rejuvenation of the reproductive system (Berry, 2003). Molting has been conducted through different techniques including photoperiod reduction, feed restriction, hormone administration, feeding dietary salt of zinc, aluminium and/or iodine (Khan et al. 2011). Molting has been associated with sudden change in physiological biochemistry which requires restoration before coming into production (Khan et al. 2011). The most important advantage of molting is the rejuvenation of reproductive system which increases tissue efficiency, development of reproductive system, loss of fat on female reproductive system, hence better post-molt performance (Park et al. 2004). Attia et al. (1994) explored that bird’s egg shell quality, albumen quality, and hatchability are influenced by molting method.
Molting is followed by ovary and oviduct histophysiological changes (De-cuypere and Verheyen 1986); affecting egg characteristics, hatchability and chick quality.
Induced molting is an effective management tool, enabling to meet egg production with demand and even providing greater economic benefit as it reduces bird cost per dozen of eggs because it lengthens the productive life of the hen (Carey and Brake 1987).Induced molting is used in the poultry industry to increase the reproductive lifespan of birds leading to new productive cycles (Laurentiz et al. 2005). In the induced molting methods, 25-30% of body mass reduction from initial weight is ideally required to achieve a maximum post-molt performance (Brake, 1993). Induced molting has been reported to improve egg production and other performance parameters (Akram, 1998; Usman et al. 2013). As to body weight loss (BWL), research studies point out that BWL levels between 25 and 30% promotes better post-molting production in a second laying cycle (Hussein, 1996). Reduction in ovary weight depends upon the duration of fasting or body weight loss levels (Berry, 2003); 15% body weight loss results in heavier eggs as compared to 20-25% (Buhr and Cunningham 1994). Post-molt reproductive improvement is related to the regression and to the regeneration of the cells of reproductive system (Brake and Thaxton 1979). Egg quality and hatchability decrease with the age of the breeder and are reported to be improved in terms of Haugh Units and overall hatchability after molting (Lapaˆo et al. 1999). Induced molting not only helps in improving production performance and egg shell quality but also increases profit by optimizing the use of replacement pullets on commercial layer farms (Bell, 2003).
The combination of feed withdrawal and light reduction was most widely used to induce molting in the US egg industry in the past. Most producers used some form of feed withdrawal for periods of 5 to 14 days in breeder birds (Bell and Kuney 2004).
It is further reported that induced molting improves the post-molt performance of the laying hens compared to the pre-molt performance, this improvement includes egg size, shell quality, internal
egg quality, and the rate of egg production. Egg size increases significantly after a molt with a higher percentage of higher grade eggs (Zeelen, 1975). Hatchability is influenced by molting method (Attia et al. 1994). Several researchers studied a relationship among hen age and hatchability (King’ori, 2011). Induced molting through feed withdrawal and photoperiod reduction is an effective method to improve egg production, egg quality, fertility and hatchability of broiler breeders (Moustafa et al. 2010).
The effect of molting in chicken and turkey is very well studied and some basic facts have been well established but its significance in quail production is still having a question mark. Reason being the availability of little information on this aspect of quail production. It is also being felt that in Pakistan, especially at Avian Research and Training Center selection for higher body weight is being practiced since last 5-6 years and with the passage of time final body weight (4 week) of quail is almost doubled. These genetically improved quails need to be subjected to maximum experimentation in order to study their potential and standardize their management requirements. Present study is also an effort in the same direction with the main objective to explore the effect of molting on productive and reproductive performance as well as subsequent progeny growth performance in Japanese quails.

Department of Poultry Production


Implemented and Maintained by UVAS Library.
For any Suggestions/Query Contact to library or Phone:+91 99239068
Website/OPAC best viewed in Mozilla Browser in 1366X768 Resolution.