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Copyright of Canadian Journal of Applied Physiology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In Algeria, rabbit meat production is small-scale, mainly on small farms with rabbits from local populations whose productivity and growth are rather low, but which are well adapted to the local environment. Of these, farmers prefer white rabbits, with the Albino or Himalayan alleles of gene C. Our objective was to verify the appropriateness of this preference for white rabbit does over a period long enough to also assess the effect of season. From September 2006 to June 2010, reproduction data from 209 females (138 white and 71 coloured) mated by 51 males from the same population were recorded. There was neither effect of sire coat colour nor any interactions between coat colour, season and physiological status of does. There was a significant relationship between coat colour (white vs. coloured) and most reproductive traits, except receptivity and fertility, in favour of coloured females. Litter size was higher by 0.67 kits born ( P = 0.041), 1.27 born alive ( P < 0.0001) and 1.04 weaned ( P = 0.0011). There was a highly significant effect of season on all the measured traits. Receptivity, fertility and prolificacy were significantly higher before the hot period; in summer, reproductive performance was depressed, but no more than during the following period, confirming the good adaptation of this local population to hot conditions. We can conclude that the preference of farmers for white animals is not justified because there is in this population an unfavourable genetic association between reproduction and Albino or Himalayan alleles of C gene, which needs to be explored in more detail. [ABSTRACT FROM AUTHOR]

Seaweeds are macroalgae, which generally reside in the littoral zone and can be of many different shapes, sizes, colours and composition. They include brown algae (Phaeophyceae), red algae (Rhodophyceae) and green algae (Chlorophyceae). Seaweeds have a long history of use as livestock feed. They have a highly variable composition, depending on the species, time of collection and habitat, and on external conditions such as water temperature, light intensity and nutrient concentration in water. They may contain non-protein nitrogen, resulting in an overestimation of their protein content, and nitrogen-to-protein conversion factors lower than 6.25, normally used for feed ingredients, have been advocated. They contain considerable amount of water. Most essential amino acids are deficient in seaweeds except the sulphur containing amino acids. Seaweeds concentrate minerals from seawater and contain 10–20 times the minerals of land plants. They contain only small amounts of lipids (1–5%), but majority of those lipids are polyunsaturated n-3 and n-6 fatty acids. Brown seaweeds have been more studied and are more exploited than other algae types for their use in animal feeding because of their large size and ease of harvesting. Brown algae are of lesser nutritional value than red and green algae, due to their lower protein content (up to approx. 14%) and higher mineral content; however brown algae contain a number of bioactive compounds. Red seaweeds are rich in crude protein (up to 50%) and green seaweeds also contain good protein content (up to 30%). Seaweeds contain a number of complex carbohydrates and polysaccharides. Brown algae contain alginates, sulphated fucose-containing polymers and laminarin; red algae contain agars, carrageenans, xylans, sulphated galactans and porphyrans; and green algae contain xylans and sulphated galactans. In ruminants, step-wise increase in the levels of seaweeds in the diet may enable rumen microbes to adapt and thus enhance energy availability from these complex carbohydrates. In monogastrics, those polysaccharides may impact the nutritional value but the addition of enzyme cocktails might help. In vivo studies on ruminants, pigs, poultry and rabbits reveal that some seaweeds have the potential to contribute to the protein and energy requirements of livestock, while others contain a number of bioactive compounds, which could be used as prebiotic for enhancing production and health status of both monogastric and ruminant livestock. Seaweeds tend to accumulate heavy metals (arsenic), iodine and other minerals, and feeding such seaweeds could deteriorate animal and human health. Regular monitoring of minerals in seaweeds would prevent toxic and other undesirable situations. [ABSTRACT FROM AUTHOR]

Abstract: Meat from rabbits reared either according to a standard (STAND) or a high quality norm (LABEL) or a low growth breeding (RUSSE) system were submitted to a sensory evaluation and to a large set of physicochemical measurements (weight of retail cuts, colour parameters, ultimate pH, femur flexure test, Warner-Bratzler shear test, water holding capacities and cooking losses). STAND rabbit meat exhibited the most juicy meat in back and in leg (p <0.01). Leg tenderness significantly decreased (p <0.001) in the rank order STAND>LABEL>RUSSE. Canonical correlation analysis showed strong correlations between physicochemical and sensory variables (R 2 =0.73 and 0.68 between the two first pairs of canonical variates). Especially, sensory tenderness and WB shear test variables assessed on raw longissimus muscle (LL) were correlated. Fibrous attribute in back was correlated with cooking loss in LL. When analysed separately only RUSSE rabbits exhibited the same relations between variables as those calculated in whole dataset. [Copyright &y& Elsevier]