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Non-spinning syndrome in Bombyx mori (L., 1758) (Lepidoptera: Bombycidae) is a serious issue for the sericulture industry. Determination of urea metabolism as an important parameter at the onset of spinning has shown the need for examining the role of urea metabolism in the non-spinning syndrome. The aim of this study was to investigate role of urea metabolism in the non-spinning syndrome by evaluating urease activity and L-arginine concentrations in the silkworm hemolymph and mulberry leaves. Additionally, urea concentrations were determined in hemolymph samples. Urease activities in hemolymph samples were almost twice as high in spinning larvae (SL) than in non-spinning larvae, 25 ± 5.8 vs 10.9 ± 2.4 units/l (P < 0.05). Urea concentrations in the SL hemolymph decreased significantly from day 5 (137 ± 13 mg/l) to day 7 (97 ± 17 mg/l) of the fifth instar (P < 0.01), it remained almost constant in NSL hemolymph (149 ± 19 to 167 ± 4 mg/l). Additionally, L-arginine concentrations in hemolymph samples obtained from NSL of 4.55 ± 0.48 mM were significantly higher than in SL at 2.72 ± 0.45 mM (P < 0.01). Changes in urease activity and L-arginine concentrations in hemolymph were similarly observed in mulberry leaves. These results suggested that changes in urea metabolism may cause or contribute to non-spinning syndrome in silkworms., Bombyx mori (L., 1758) (Lepidoptera: Bombycidae)’de görülen koza örememe sendromu, ipekböcekçiliği sektöründe ciddi bir sorun olarak görülmektedir. Üre metabolizmasının koza örme başlangıcında önemli olması, bu metabolizmanın koza örememe sendromunda olası rolünün incelenmesi gereğini doğurmuştur. Bu çalışmanın amacı, ipekböceği hemolenfinde ve dut yapraklarında üreaz aktivitesi ve L-arginin konsantrasyonlarını saptayarak, koza örememe sendromunda üre metabolizmasının rolünü araştırmaktır. Bu parametreler ek olarak hemolenf örneklerinde üre konsantrasyonları da ölçülmüştür. Koza ören grubun hemolenfinde üreaz aktivitesi (25 ± 5,8 units/l), koza örmeyen gruba (10,9 ± 2,4 units/l) göre iki kat daha yüksek bulunmuştur (P < 0.05). Koza ören larvaların hemolenfinde üre konsantrasyonu 5. dönemin 5. gününden (137 ± 13 mg/l) 7. gününe önemli seviyede azalırken (97 ± 17 mg/l; P < 0.01), koza öremeyen larvalarda hemen hemen sabit kalmıştır (149 ± 19 mg/l’den 166 ± 4 mg/l’ye). Koza öremeyen larvaların hemolenf örneklerinde L-arginin konsantrasyonu (4.55 ± 0.48 mM), koza ören larva grubundan anlamlı ölçüde yüksek bulunmuştur (2.72 ± 0.45 mM; P < 0.01). Hemolenfteki üreaz aktivitesi ve L-arginin konsantrasyonlarında gözlemlenen değişiklikler benzer şekilde dut yapraklarında da saptanmıştır. Bu sonuçlar, üre metabolizmasındaki olası bir baskılanmanın ipekböceklerinde görülen koza örememe sendromuna katkıda bulunabileceği ve/veya bunun sonucu olabileceğini düşündürmektedir.

Silkworm, Bombyx mori L. is an economic insect that has great importance on cocoon and silk production. The development of sericultural industry depends on quality and yield in terms of qualitative and quantitative silkworm characters. Mature larval weight and silk gland mass are important factors in silkworm breeding. Silk gland mass has significant impact on the synthesis of silk protein in fifth larval stage. The investigation was conducted to evaluate the correlations between silk gland mass and mature larva weight of M and ZF (China), and N and ZB (Japan) lines and their hybrids MxN, ZFxZB. In this research, silkworm lines and hybrids were reared at the laboratory with 600 silkworm larvae for each four lines and their hybrids to determine these silkworm traits. Analysis of variance indicated that the mean values in Chinese lines and hybrids were found to be significant (P

The aim of this study was to investigate effects of conventional-cage (CC), enriched-cage (EC), and free-range (FR) systems and hen age on internal and external egg quality parameters of layers (Lohmann Brown). A total of 720 eggs were analyzed for egg weight (EW), shell weight (SW), yolk weight (YW), albumen weight (AW), shell thickness (ST), shell breaking strength (SBS), shape (SI), albumen (AI), yolk index (YI) of eggs, shell ratio of eggs (SR), albumen ratio of eggs (AR), yolk ratio of eggs (YR), yolk color (YC), and Haugh unit (HU). The highest EW, YW, AW, SW, AI, YI, HU (all P < 0.001), and SI values were found in FR system eggs compared with CC and EC system eggs (P = 0.045). The SBS, ST, YC, SR, YR, and AR were found similar in all housing systems. There was an interaction between the housing system and hen age for EW, SW, YW, AW, SBS, ST, AI, YC, HU, AR (all P < 0.001), SI (P = 0.003), SR (P = 0.001), and YR (P = 0.001) of eggs. It can be concluded that eggs in the FR system were better in overall quality than eggs from CC and EC systems.

Ipek, A., Karabulut, A., Sahan, U., Canbolat, O. and Yilmaz-Dikmen, B. 2009. Effect of different diets on the behaviour of slow-growing broiler genotype. J. Appl. Anim. Res., 35: 87–90. A total of 420 male day-old-chicks of a slow-growing genetic line (Hubbard ISA Red JA) were used as the trial material. The treatment groups were: Dilute-AL (energy and protein diluted diet fed ad libitum), Dilute-R (restricted energy and protein diluted diet), High-AL (high energy and protein diet fed ad libitum) and High-R (restricted high energy and protein diet). Restricted birds showed a greater percentage of time spot pecking, preening and in feather maintenance and less time resting than birds fed ad libitum but the differences were relatively small.

The present study was conducted to determine the effect of cold stress on broiler performance and ascites susceptibility. Male chicks were obtained from a commercial strain of broiler breeders. The trial was divided into two treatments (control and cold stress groups). Ascites was induced in broiler chickens in the trial by exposing the chickens to low temperature (Ta) and by supplying a pelleted diet. The two experimental treatments consisted of. 1) Control group, 33.3 degrees C the 1(st) wk, 30.2 degrees C the 2(nd) wk, and 27.5 degrees C the 3(rd) wk. 2) Cold stress group, 29.0 degrees C the 1(st) wk, 26.4 degrees C the 2(nd) wk, and 23.1 degrees C the 3(rd) wk. From the end of the 3(rd) wk all broilers were reared to 6 wk of age at a constant temperature of 21 degrees C. There was significant difference in live BW during wk 1 to 5. The control group was consistently the heaviest; however, at 6 wk of age, both groups weighed the same. Body weight gain up to 3 wk was significantly decreased by cold stress. During wk 3 and 6 the chicks in the cold stress group had greater BW gain compared with the chicks in the control group. There were significant differences in mortality due to ascites between the groups. During wk 3 and 6 the cold stress group exhibited the most ascites mortality (9.52%) when compared with the control group (1.90%). At 5 wk of age cold stress condition caused significant changes in packed cell volume (PCV), hemoglobin (Hb) and red blood cell counts (RBC). Right ventricle weight was significantly heavier in the cold stress group than the control. There were also significant differences in right ventricle/total ventricle (RV/TV) ratios at 5 wk. the right ventricle/total ventricle ratios in the cold stress group was higher (0.25) than the control group (0.20). It was concluded that, fast growth and cold temperatures are the primary triggers for ascites during commercial broiler production.

The aim of the current study was to determine the effects of different eggshell temperatures (EST) during 10 to 18 d of incubation on embryonic development, hatchability, chick quality, first-week broiler performance. The EST were maintained within the temperature ranges of 33.3 to 36.7, 37.8 to 38.2, and 38.9 to 40.0 degrees C for the low, control, and high EST treatments, respectively. From d 15 to 18, embryo weight and relative embryo weight were found to be similar in the low and high EST groups. Salable chicks and hatchability of total eggs was found to be higher in the control EST group. Between d 10 and 17 of incubation, embryonic mortality in low, control, and high EST groups was determined to be 1.6, 0.8, and 2.0%, respectively. From d 18 to hatch, embryonic mortality and rate of dead and cull chicks were found to be significantly different. Hatching in high EST group was completed 26 h early, although hatching in low EST group was completed 10 h later than the control EST group. On the of hatching day, chick weight and length were found to be 39.5, 41.0, and 42.5 g, and 18.5, 21.4, and 19.1 cm in low, control, and high EST groups, respectively. The highest residual yolk sac weight and relative residual yolk sac weight were observed in high EST group as 7.7 g and 18.7%. Yolk-free chick weight and relative yolk-free chick weight were highest in the control EST group. At 1 wk of age, the BW in low, control, and high EST groups were determined as 131.1, 140.0, and 140.8 g, respectively. No significant difference was found for feed intake and feed conversion among treatments for wk 1. The mortality during the first week did not differ among groups; however, a higher mortality rate was observed numerically in the high EST group. In conclusion, embryo development, incubation parameters, chick quality, and the first week performance are affected by small changes in the EST.

La presente etude a ete conduite pour evaluer l'utilisation possible d'un apport supplementaire d'oxygene pendant les trois derniers jours d'incubation sur les performances du poulet de chair, l'apparition d'ascite et quelques parametres physiologiques. Au 18 e jour d'incubation, les oeufs fertiles ont ete divises en deux groupes. De 18 a 21 jours, les oeufs ont ete places dans deux eclosoirs, l'un (groupe temoin) sous conditions atmospheriques normales (20, 9 ± 0,5 % O 2 a 754 ± 2 mmHg) et l'autre (groupe experimental) sous atmosphere enrichie en oxygene a 23,0 ± 0,5 %. L'apport d'oxygene a eu un effet significatif sur le poids initial des poussins. A six semaines d'âge, le poids corporel, la vitesse de croissance et la consommation d'aliments ont ete accrus avec la pression partielle en oxygene la plus elevee, alors que l'indice de consommation a ete diminue. La mortalite en general et la mortalite due a l'ascite en particulier n'ont pas differe entre les groupes. A cinq semaines d'âge, l'apport d'oxygene n'a provoque aucun changement significatif pour la numeration des globules rouges, le taux d'hemoglobine et de glucose. Toutefois, l'hematocrite a ete sensiblement augmente lorsque la pression partielle d'O 2 est passee de 20,9 a 23,0 %. Aucune difference significative n'a ete observee entre les deux groupes pour le poids du ventricule droit, le poids du ventricule gauche + septum interventriculaire, le poids ventriculaire total et le rapport du poids du ventricule droit au poids ventriculaire total (VD/VT).