STUDIES REGARDING THE INFLUENCE OF REARING SYSTEM FOR LAYING HENS ON THEIR HEALTH STATE

C. Spridon, Paula Viorela Druc, Carmen Irimia (Gavrilescu), Roxana Nicoleta Raţu, M.G. Usturoi

Abstract
    Civic associations succeed to change the legislation regarding rearing of laying hens. Phenomenon lead to adaptation of some technological solutions which offer birds those life conditions specific both to welfare and also to obtain superior productive performances. In the current paper are presented the results of a study which aimed the survival rate of laying hens reared in two different systems: in batteries and in lofts. Research took place during 41 weeks, starting with the age of 20 weeks and were consisted in evaluation of flock losses and the causes which generate them. The obtained data shown that total flock losses were of 6.41% for the hens reared in lofts and 4.26% at the ones reared in batteries, face to 3.1% which is recommend by the producer of the utilised hybrid. Regarding the causes which generate the flock losses, at variant with accommodation in lofts was founded a higher rate of hens with mechanical accidents (51.7% face to only 42.1% in batteries) due to frequent movements both horizontally and vertically, to the food/water sources or to laying/rest area. Hens accommodated in batteries presented a higher incidence of obstetrical diseases (34.7% vs. 29.6%) and internal ones (23.2% vs. 18.7%) caused by more intense laying rhythm in comparison with the hens from lofts. Data obtained by us regarding survival rate of laying hens flocks show the fact that this one is clearly influenced by the utilised rearing system, but it is also the dependence of some perturbation factors which could be eliminated by adaptation of some adequate measures.

Key words: hens, eggs, rearing, technology, survival