The influence of AME(n) concentration of the diet on productive performance and egg quality traits was studied in Hy-Line brown egg-laying hens differing in initial BW from 24 to 59 wk of age. Eight treatments were arranged factorially with 4 diets varying in energy content (2,650, 2,750, 2,850, and 2,950 kcal of AME(n)/kg) and 2 initial BW of the hens (1,733 vs. 1,606 g). Each treatment was replicated 5 times (13 hens per replicate), and all diets had similar nutrient content per unit of energy. No interactions between energy content of the diet and initial BW of the hens were detected for any trait. An increase in energy concentration of the diet increased (linear, P < 0.05; quadratic P < 0.05) egg production, egg mass, energy efficiency (kcal of AME(n)/g of egg), and BW gain (P < 0.05) but decreased ADFI (linear, P < 0.001) and feed conversion ratio per kilogram of eggs (linear, P < 0.01; quadratic P < 0.01). An increase in energy content of the diet reduced Haugh units and the proportion of shell in the egg (P < 0.01). Feed intake (114.6 vs. 111.1 g/hen per day), AME(n) intake (321 vs. 311 kcal/hen per day), egg weight (64.2 vs. 63.0 g), and egg mass (58.5 vs. 57.0 g) were higher for the heavier than for the lighter hens (P < 0.01), but feed conversion ratio per kilogram of eggs and energy efficiency were not affected. Eggs from the heavier hens had a higher proportion of yolk and lower proportion of albumen (P < 0.01) and shell (P < 0.05) than eggs from the lighter hens. Consequently, the yolk-to-albumen ratio was higher (P < 0.001) for the heavier hens. It is concluded that brown egg-laying hens respond with increases in egg production and egg mass to increases in AME(n) concentration of the diet up to 2,850 kcal/kg. Heavy hens had higher feed intake and produced heavier eggs and more egg mass than light hens. However, feed and energy efficiency were better for the lighter hens.

Mohiti-Asli, M., Shariatmadari, F., Lotfollahian, H. and Mazuji, M. T. 2008. Effects of supplementing layer hen diets with selenium and vitamin E on egg quality, lipid oxidation and fatty acid composition during storage. Can. J. Anim. Sci. 88: 475Á 483. A 7-wk trial was carried out to investigate the effect of vitamin E and inorganic and organic selenium added to hens' diet on quality and lipid stability of eggs during storage. One hundred forty-four Hy-Line W-36 hens (63-wk of age) were divided into six equal groups. Five groups received a basal diet supplemented with 0.4 mg kg(1 sodium selenite or selenium yeast, 200 mg kg (1 vitamin E or a combination of selenium and vitamin E; whereas the control group received no supplementation. Hen production was assessed daily and fresh egg quality parameters were determined every 2 wk. Eggs were stored under different conditions (48C, 23Á278C or 318C) for 14 d. Eggs were analyzed for quality characteristics, egg component weight, Malondialdehyde values as a secondary oxidation product and yolk fatty acid (FA) composition. The performance of the hens and egg weights were not affected either by the source of the selenium or by the vitamin E. The inclusion of selenium or vitamin E in the diet significantly increased their concentrations in the egg. The supplemented diets also improved egg quality, oxidative stability and fatty acid composition during storage.Key words: Vitamin E, selenium, lipid peroxidation, egg fatty acid composition, storage Mohiti-Asli, M., Shariatmadari, F., Lotfollahian, H. et Mazuji, M. T. 2008. Incidence du se´le´nium et de la vitamine E dans la ration des pondeuses sur la qualite´des aeufs, l'oxydation des lipides et la composition en acides gras durant l'entreposage. Can. J. Anim. Sci. 88: 475Á483. Un essai de sept semaines devait pre´ciser les effets de la vitamine E ainsi que du se´le´nium mine´ral ou organique, ajoute´s à la ration des pondeuses, sur la qualite´des aeufs et la stabilite´des lipides pendant l'entreposage. Cent quarante-quatre poules W-36 Hy-Line (de 63 semaines) ont e´te´re´parties en six groupes e´gaux. Cinq groupes ont rec¸u la ration de base enrichie de 0,4 mg de se´le´nite de sodium ou de se´le´nium de levure par kg, ou 200 mg de vitamine E ou de se´le´nium et de vitamine E par kg, tandis que le groupe te´moin n'a rec¸u aucun supple´ment. La ponte a e´teé´v alue´e quotidiennement et les parame`tres qualitatifs des aeufs frais ont e´te´de´termine´s une semaine sur deux. Les aeufs ont e´te´garde´s 14 jours dans des conditions varie´es (4 8C, 23Á27 8C ou 31 8C). On a ensuite analyse´leur qualite´, le poids de chaque composante, la concentration de malondialdehyde en tant que produit secondaire de l'oxydation et la composition du jaune en acides gras. Le rendement des pondeuses et le poids de l'aeuf ne sont pas affecte´s par la source de se´le´nium ni la vitamine E. L'enrichissement de la ration avec du se´le´nium ou de la vitamine E augmente sensiblement la concentration de ces substances dans l'aeuf. Les supple´ments ame´lior...

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A trial was conducted to study the effects of the aromatic plant thyme, a commercial probiotic (Protexin) and avilamycin on broiler performance, blood biochemical parameters and also the antibody response to sheep red blood cells. A total of 750 broilers were assigned into five replicate groups for each of five dietary treatments, namely; control (C), 2.5 mg/kg avilamycin (AB), 0.1 g/kg commercial probiotic (P), 5 g/kg ground thyme (T1), and 7.5 g/kg ground thyme (T2). In general, body weight, feed consumption and feed conversion ratio were not affected by dietary treatments compared to the control birds (P>0.05). Birds fed the P supplemented treatment had the greatest serum protein levels (P<0.001) and highest albumin levels (P<0.001) when compared with control birds, while the birds fed T2 had the lowest (P<0.001). Dietary supplementation reduced (P<0.001) cholesterol and triglyceride concentration in serum of broilers, with the effect were more noticeable by P supplements. Moreover, blood calcium and phosphorus concentrations were higher (P<0.001) in birds fed the P-supplemented diet compared to the birds fed the control diets.This study suggests that probiotic supplementation in particular, and to an intermediate extent ground thyme supplementation in diets of broiler, resulted in chicks with favorably improved blood biochemical parameters and mineral utilization, compared to the birds fed diets supplemented with avilamycin or without any supplementation.