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This study aimed to compare feed efficiency measures of Nellore beef cattle on different residual intake and gain (RIG) classes. We used data from 610 animals weighing on average 236.33 kg and average of 283 days of age from feedlot performance tests carried out between 2005 and 2012. Animals were grouped based on RIG into three different classes: high RIG (>?mean?+?0.5 standard deviation (SD), most efficient; n?=?193), medium RIG (mean?±?0.5 SD; n?=?235), and low RIG (<?mean – 0.5 SD, least efficient; n?=?182). Residual feed intake (RFI), residual gain (RG), feed conversion ratio (FCR), feed efficiency (FE), relative growth rate (RGR), and Kleiber ratio (KR) of animals in each RIG class were compared by Tukey test at 1% of probability. Phenotypic correlations between variables were evaluated as well. Animals on high RIG class showed lower dry matter intake (P?<?0.01) and higher average daily gain (P?<?0.01) than low RIG animals. Consequently, high RIG animals had lower FCR (P?<?0.01) and higher FE (P?<?0.01) than those animals in low RIG class. The most efficient animals based on RIG were also the most efficient animals based on RG and RFI. RIG was negatively correlated to dry matter intake (P?<?0.01) and FCR (P?<?0.01), and a positive correlation was found between RIG and FE (P?<?0.01). Therefore, RIG appears to be a good parameter to select animals with reduced dry matter intake and high productive performance.

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A study of cultured healthy turbot haemochemistry is based on blood data of 107 twelve- to fifteen-month-old fish. Six successive samplings were carried out in the Centre Oceanologique de Bretagne (COB) and in two aquaculture experimental stations in Brittany. Turbot were not fed 36 h before sampling.Thirteen parameters were studied: in the blood, haematocrit and haemoglobin, and in the plasma, glucose, total protein, total cholesterol, triglycerides, phospholipids, sodium, potassium, chloride ion, calcium, magnesium and mineral phosphorus. Moreover, electrophoresis of plasma proteins was systematically carried out. Indicative haemochemistry standards are proposed from these results.A parallel is drawn between the present results and previously known haemochemistry data in turbot and other flat-fish.  相似文献   
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The blue shark (Prionace glauca) is the most frequently captured shark in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. As part of cooperative scientific efforts for fisheries and biological data collection, information from fishery observers, scientific projects and surveys, and from recreational fisheries from several nations in the Atlantic and Indian Oceans was compiled. Data sets included information on location, size and sex, in a total of 478,220 blue shark records collected between 1966 and 2014. Sizes ranged from 36 to 394 cm fork length. Considerable variability was observed in the size distribution by region and season in both oceans. Larger blue sharks tend to occur in equatorial and tropical regions, and smaller specimens in higher latitudes in temperate waters. Differences in sex ratios were also detected spatially and seasonally. Nursery areas in the Atlantic seem to occur in the temperate south‐east off South Africa and Namibia, in the south‐west off southern Brazil and Uruguay, and in the north‐east off the Iberian Peninsula and the Azores. Parturition may occur in the tropical north‐east off West Africa. In the Indian Ocean, nursery areas also seem to occur in temperate waters, especially in the south‐west Indian Ocean off South Africa, and in the south‐east off south‐western Australia. The distributional patterns presented in this study provide a better understanding of how blue sharks segregate by size and sex, spatially and temporally, and improve the scientific advice to help adopt more informed and efficient management and conservation measures for this cosmopolitan species.  相似文献   
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The objective was to estimate genetic correlations between body weight (BW), scrotal circumference and visual evaluation scores of body conformation measured at standard ages in Guzerat cattle. All measurements were performed at 205 (weaning age), 365, 450 and 550 days of age; for BW, two additional measurements (at birth and 120 days of age) were realized. The data utilized in this study were retrieved from a database of the Brazilian Association of Zebu Breeders that contained information of registered Guzerat animals born between 1970 and 2013. Genetic parameters were estimated in bi‐trait analyses by using Bayesian inference. Genetic correlations between BW at 205 and 450 days of age with other traits were high and positive, whereas the correlations between visual evaluation scores with other traits were moderate. Based on correlations herein obtained, we conclude that selection based on BW results in increased visual scores and scrotal circumference, leading to improvements in productive performance and animals with best body conformation.  相似文献   
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