A bulk of studies on the assay of gonadotrophic hormone content of the anterior pituitary from the animals in various reproductive conditions has been done. Riley and Fraps(1942b) assayed pituitary glands from chickens in various reproductive stages, judging the gonadotrophic potency by the increment of uterine weights of immature mice, and concluded that glands from non-laying hens produced a ...

The objective of the study was to determine the effect of Quantum Blue phytase on P utilisation and bone parameter in laying hens fed barley, oat and soybean meal based diets. Over a period of 40 days 64 laying hens (from 29 weeks of age) were distributed to 4 treatments (8 cages, two birds each). Experimental diets with no inorganic P added were supplemented with 0, 150, 300 or 1200 FTU phytas...

OBJECTIVE The objective of this experiment was to investigate the effect of dietary β-mannanase on productive performance, egg quality, and utilization of dietary energy and nutrients in aged laying hens raised under hot climatic conditions. METHODS A total of 320 84-wk-old Hy-line Brown aged laying hens were allotted to one of four treatments with eight replicates in a completely randomized ...

The deposition of dietary folic acid (FA) into the chicken egg is likely regulated by its conversion to 5-methyltetrahydrofolate (5-MTHF), the predominant form of this vitamin in eggs (>80%). Supplementation of 5-MTHF in the laying hens′ diet may therefore enhance total egg folate concentrations. To this end, a study was conducted using equimolar concentration of either FA or 5-MTHF in diets fe...

the aim of the present study was to investigate the possibility of improving egg lipids and fatty acids composition of laying hens through inclusion of olive cake plus barley malt rootlets in the diets. seventy, 54-week-old, lohman laying hens were fed for a 12 weeks laying period on 3 iso-caloric and iso-nitrogenous diets contained 0 (control), 28.5 g olive cake (oc) + 25.5 g barley malt rootl...

Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans with structure similar to 17-β-estradiol and capable of binding to estrogen receptors (ERs).This experiment was conducted to demonstrate the effect of isoflavones on estradiol concentration in blood and its influence on the productive performances in ISA Brown laying hens fed with supplemented feed with large...

In this experiment 180 Azerbaijan province native laying hens from 28 to 40 weeks were separated in 6 treatments and 3 replicates (10 birds per replicate) as a (2 × 3) factorial arrangement of treatments in a completely randomized design. Treatments included two levels of dried tomato pomace (DTP) (8 and 16%) and 3 types of using methods (unprocessed, alkali and acid processed). The results sho...

Feather pecking (FP) in laying hens may cause mortality due to cannibalism. Novel breeding methods using survival days of group-housed siblings allow for the genetic selection of laying hens with low mortality (LML: low mortality line) due to cannibalism. Previous studies have demonstrated less fear-related behavior and also less FP in LML hens compared to CL. Selection also caused changes in l...

This study was conducted to determine effects of dietary NaHCO supplementation on egg 3 production and egg quality during the late laying period. Hisex Brown layers, 54 wks of age, were blocked according to the cage location and then assigned randomly to receive one of four diets containing 0, 0.1, 0.2, or 0.4% NaHCO for 75 d. Each diet was replicated in 6 groups; each consisting of 2 cages con...

During recent decades productivity of laying hens increased substantially (Elliot, 2008). Not only egg number, egg mass, and feed conversion has increased but also persistency of lay has improved. As such, this must have implications on the optimal amino acid nutrition of current laying hen strains. Simply stated, increasing egg mass output per hen means an increased amino acid output which has...