Effects of early and chronic exposure to high temperatures on growth performance, carcass parameters and fatty acids of subcutaneous lipid of broilers

This study was conducted to assess the effects of early and chronic exposure of broilers at a scorching temperature on growth performance, carcass parameters, fatty acid deposition and composition of subcutaneous lipids (SCL). Three hundred male chicks (Hubbard origin) of a day are reared for 50 days. They are divided into three groups, each of cent chicks. The chronic thermal environments are applied from the 8th growing day: a neutral temperature (NT: 25 ± 2°C) for the first one, a moderate summer temperature (MT: 32 ± 2°C) for the second and hot temperature (HT: 37 ± 2°C) for the third. The results were summarized as follows: (1) from the 40th day, a decrease of 37 g/d of feed intake (FI) related to HT was observed; (2) a higher body weight (BW) of NT chickens was recorded from the 40th day; (3) regarding the early breeding, a higher daily weight gain (DWG) was recorded in HT chickens at the end of rearing; (4) compared to other temperature, the feed conversion ratio (FCR) of HT chickens was significantly better from 40th day; (5) at the end of breeding, the yields EC/BW: eviscerated carcass weight (EC) on body weight (BW) were comparable as recorded in NT and HT chickens; (6) at the end of breeding, a decreased weight of pectoral muscle (PM) associated with the HT was observed: -17 and - 20% compared with TM and TN, respectively; (7) a higher deposit of SCL up to 105g/Chicken and SCL/EC (+7.3% compared with NT) occur in the HT chickens mainly at the end of rearing; (8) conversely, the abdominal fat weight (AF) was higher in NT chickens from the 32th day; (9) compared with NT chickens, an increase in the proportion of saturated fatty acids (SFA) and polyunsaturated (PUFA) of SCL was obtained in HT chickens of 50 days. No temperature effect on the monounsaturated fatty acids proportion (MUFA) of LSC has been highlighted. Finally, the HT resulted in a significant decrease of the UFA/SFA ratio reflecting a degree of SCL saturation greater in HT chicken carcass; (10) these results have shown that chickens can tolerate early and chronic higher temperatures.Keys words: Temperature, broilers, growth, subcutaneous lipids, fatty acids

Growth performances, carcasses parameters and meat fatty acid composition of lamb fed green oak acorns (Quercus ilex) based diet

The aim of this experiment is to compare the effects of diets containing green oak acorns (GO) and barley (BL) on the growth performances, carcasses parameters and the composition in fatty acids of lambs. Twogroups of five lambs each were fed, respectively, during 105 days with diets containing 50% of oaks acorns and 50% of barley. At the end of the test, the animals of the two diets expressed comparable body weights and weight gain. A significant difference (P < 0.05) was observed for the thickness of fat cover which is 3 mm for the BL group against 1.6 mm for GO group even if no significant difference was revealed concerning the output with slaughtering. The intramuscular lipids were significantly higher (P < 0.05) in the group of animals fed with GO diet compared to the BL diet (3.88 vs 2.83 g.100-1 g of muscle). Among the saturated fatty acids (SFA), the stearic acid significantly appeared in higher proportion (P <0.05) in GO diet (20.8 vs 18.1%) whereas the palmitic acid is prevalent in the group of animals fed with the BL diet (25 vs 30%). For the  polyunsaturated fatty acid (PUFA), no significant difference was observedbetween the two groups. The linoleic acid is prevalent among the PUFA of two groups without significant difference. The linolenic acid is higher in the animal fed BL. The n-6: n-3 ratio is higher in the BL group (8.9 vs 7.3). At the end, the low level of incorporation of PUFA in muscle of the lamb because of biohydrogenation, suggests us supplementing the diet by green grass

Fatty acid profile and assessment of heavy metals content of Sardina pilchardus captured in the Algerian coast

Total lipids, fatty acid composition and heavy metal content of Sardina pilchardus fillet samples captured in February 2014 in Beni saf, Mostaganem, Ghazaouet, Algiers and Jijet coast were evaluated. Total lipid content was related to the five sites of catch (p<0.05), ranging from 7.18 g 100g-1 for Algiers to 10.07g 100g-1 for Beni saf. The fatty acid composition of S. pilchardus shows a high content of polyunsaturated fatty acids (PUFAs) dominated by n-3 fatty acids eicosapentaenoic acid (EPA C20:5 n-3) and docosahexaenoic acid (DHA C22:6n-3) with maximum rates of 15.75% and 33.42%, respectively (p<0.05). The saturated fatty acid (SFA) content was important in different samples of sardines, ranging from 35.50% to 41.32% according to sites of capture (p<0.05). Concerning the heavy metals, the levels of lead (Pb) ranged from 0.013mg to 0.024mg, however those of mercury (Hg) varied from 0.080 mg to 0.130 mg (p<0.05), which affects the health value of the fish species