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961.
The effect of extreme cooling and the temperature for crystallization on the quality of turkey sperm
Two experiments were performed to evaluate the influence of supercooling and temperature of ejaculate crystallization in white broad-breasted male turkeys, hybrid Ivagal, on the motility, proportion of live and morphologically normal spermatozoa. As follows from the results obtained by testing the quality of spermatozoa, increasing supercooling and decreasing temperature of crystallization have a destructive effect. 相似文献
962.
Changes in the mineral content of bones in fibrous osteodystrophy in standard minks and Arctic foxes
Laboratory characteristics of a metabolic disease (Osteodystrophia fibrosa) in standard young minks and arctic foxes is described. In comparison with the control group, while the biochemical characteristics of the blood samples of arctic foxes was not very different from the control group in the contents of macroelements (calcium, phosphorus, magnesium), significant differences were revealed by the analyses of the bone samples of os femoris. In young minks the ash weight in 1 g of fat-free dry matter made only 321.94 mg (52.45%), while in the control group 613.82 mg. A similar decrease (P less than 0.01) was observed, in comparison with the control, in the contents of calcium and phosphorus (44.75% and 56.90%). A slight increase in the magnesium content is not statistically significant. Evaluation of ash content in os femoris in young arctic foxes gave similar results. Biochemical characteristics of their blood showed a significant increase in the activity of alkaline phosphatase. An application of the chemical analyses of bones to diagnosing metabolic disturbances in fur animals is discussed. 相似文献
963.
H.M. Díaz-Mula P.J. Zapata F. Guillén D. Martínez-Romero S. Castillo M. Serrano D. Valero 《Postharvest Biology and Technology》2009,51(3):354-363
Eight plum cultivars (four dark-purple and four yellow) were harvested at the commercial ripening stage, and changes of fruit quality properties were evaluated during cold storage and subsequent shelf-life, with special emphasis on bioactive compounds (phenolics, anthocyanins and carotenoids) and antioxidant activity (TAA). From the eight plum cultivars, four showed the typical climacteric ripening pattern (‘Blackamber’, ‘Larry Ann’, ‘Golden Globe’ and ‘Songold’) while four behaved as suppressed-climacteric types (‘Golden Japan’ ‘Angeleno’, Black Diamond’ and ‘TC Sun’), the latter being described for the first time. At harvest, large variations in phytochemicals and antioxidant activity were found among cultivars in peel and pulp tissues, although phytochemical concentration and antioxidant activity were higher in the peel than in the flesh (2–40-fold depending on the bioactive compound). During storage, increases in total phenolics for all cultivars (peel and pulp), in total anthocyanin content in the peel of the dark-purple plums, and total carotenoids in the peel and pulp of the yellow cultivars were observed. This behaviour of the bioactive compounds was reflected in TAA changes, since hydrophilic-TAA (H-TAA) was correlated with both phenolics and anthocyanins, while lipophilic-TAA (L-TAA) was correlated with carotenoids. L-TAA comprised about 30–50% of the TAA in plum tissues. Carotenoids and phenolics (and among them the anthocyanins) could be the main lipophilic and hydrophilic compounds contributing to L-TAA and H-TAA, respectively. No significant loss of bioactive compounds and TAA occurred during prolonged plum storage. Moreover, for a better evaluation of the antioxidant potential of plums, the contribution to carotenoids should not be overlooked. 相似文献
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969.
Sources of casein protein and wheat gluten were analysed for the content of proteins, fats, saccharides, water and amino acids. The chemical score of the amino acids and the ratio of essential and non-essential amino acids (E/N) were determined. In rats (males) at the age of 120 days, given the diets for 14 days, the optimal and maintenance physiological daily rations were determined from the changes of body nitrogen, body water and weight dependent on the protein intake, using the method of increasing casein protein and wheat gluten content from 0 to 40 per cent in the diet. In 120-134-day-old rats, the optimal daily dose was 1.75 g of casein protein (7.5 per cent of all proteins in the diet) and 2.46 g of wheat gluten protein (10 per cent of all proteins in the diet). As to the maintenance rations determined from the weight changes, body nitrogen and body water in dependence on the protein intake, in these rats the successive daily rations were 1216 mg, 1214 mg and 1302 mg for the casein protein, and 1731 mg, 1760 mg and 1861 mg for the wheal gluten protein. 相似文献
970.
Fluctuation in the concentration of sex steroids and aflatoxin B1 in the seminal plasma of boars and its relation to sperm production 总被引:1,自引:0,他引:1
The concentration of testosterone, 17-beta oestradiol and aflatoxin B1 were studied in the semen plasma of 21 boars of four breeds for the period of twelve months. The following spermiological parameters were investigated: semen volume, sperm concentration, percentage of abnormal spermatozoa, and survival of spermatozoa. The fertilizing capacity of ejaculates was evaluated according to the conception rate of sows and gilts after the first insemination, according to the average number of piglets per litter and average number of live-born piglets per litter. The highest aflatoxin B1 residues in sperm were recorded in March to May and were related with aflatoxin concentration in feed ration. The group of boars with fertility disorders had more aflatoxin in their sperm (up to 100 pmol . l-1), lower sperm concentration, lower survival of spermatozoa, and a larger proportion of abnormal spermatozoa. The year season had a significant influence on the concentration of the hormones. The highest average value of testosterone (10.2 +/- 1.28 nmol) was obtained in autumn and lower values were recorded in winter. The changes in 17-beta estradiol concentration were similar to the changes in testosterone content, with the maximum value in November (0.249 nmol X 1(-1]. The boars with reproduction disorders had a significantly lower concentration of 17-beta oestradiol. Significant correlations were found between the concentration of the hormones, semen volume, and sperm concentration. 17-beta oestradiol also had a significant positive correlation to abnormal spermatozoa and to the activity of aspartate aminotransferase. 相似文献