Finishing cattle at pasture at 30 months of age or indoors at 25 months of age: Effects on selected carcass and meat quality characteristics

To examine the effect of a modification of a typically Irish dairy calf-to-beef production system, Charolais × Friesian steers were offered a finishing ration of grass silage ad libitum and 5.6 kg concentrates daily for 174 days prior to slaughter at 25 months of age or grass silage ad libitum for 174 days, followed by pasture for 167 days and slaughter at 30 months of age. Finishing at pasture increased carcass weight (376 vs. 342 kg) but did not affect intra-muscular lipid concentration (28 vs. 24 g/kg). Finishing at pasture decreased Longissimus thoracis et lumborum lightness (35.6 vs. 36.9) and increased shear force of muscle at 2 (8.54 vs 4.32) and 7 days (5.21 vs 3.64 kg) post-mortem but not at 14 days post-mortem (4.45 vs. 3.42 kg). Finishing at pasture did not affect the sensory characteristics of tenderness, juiciness, firmness or chewiness and tended (P < 0.1) to decrease texture and acceptability. It is concluded that modification of this beef production system as described, had minor effects on beef quality which are unlikely to be of commercial significance.     

五个甘蓝自交系种株发育与开花结实特性研究

对5个甘蓝自交系(09335#、09336#、09337#、09338#、09340#)的植株形态、物候期、开花结荚、果实特征以及亲和性进行了鉴定。结果表明:09335#和09337#的各物候期早,植株生长势强,侧枝数多,花期授粉与蕾期授粉结荚率高、花期和蕾期亲和指数也较高,为较优良自交系;09336#和09340#居中,09338#较差。     

Effects of cage netting colour and density on the skin pigmentation and stress response of Australian snapper Pagrus auratus (Bloch & Schneider, 1801)

The unnaturally dark pigmentation of cultured Australian snapper Pagrus auratus can be improved through dietary astaxanthin supplementation and by holding fish in tanks with a white background. The practical application of these laboratory‐based findings was examined with two experiments to establish if the advantages of transferring fish to light coloured tanks before harvest could be achieved on‐farm using white cages and to determine the effects of fish density on skin colour. For the first experiment, snapper (mean TL=29.7 cm) were transferred from a commercial snapper sea cage to black or white netted cages and fed diets supplemented with unesterified astaxanthin (supplied as Lucantin^® Pink, BASF) at 0 or 39 mg kg^?1 for 42 days. Skin colour was measured using the CIE (black–white), (green–red), (blue–yellow) colour scale. Snapper held in white netting cages became significantly lighter (higher ) than snapper held in black cages; however, values were not as high as previous laboratory‐based studies in which snapper were held in white plastic‐lined cages. Snapper fed astaxanthin displayed significantly greater and values, and total carotenoid concentrations after 42 days. In addition, total carotenoids were higher in fish from black than white cages. The second experiment was designed to investigate whether density reduced the improvements in skin colour achieved by holding fish in white coloured cages and whether cage colour affected stress. Snapper (mean weight=435 g) were acclimated to black cages and fed 39 mg kg^?1 astaxanthin for 44 days before transferring to black or white plastic‐lined cages at 14 (low), 29 (mid) or 45 (high) kg m^?3 for 7 days after which time skin colour, plasma cortisol and plasma glucose concentrations were measured. Skin lightness () was greater in snapper transferred to white plastic‐lined cages with the lightest coloured fish obtained from the lowest density after 7 days. Density had no effect on plasma cortisol or glucose levels after 7 days, although plasma cortisol was elevated in snapper from black cages. For improved skin colouration we recommend feeding unesterified astaxanthin at 39 mg kg^?1 for approximately 6 weeks and transferring snapper to white plastic‐lined cages or similar at low densities for short periods before harvest rather than producing fish in white netting sea cages subject to biofouling.     

Quality characteristics in raw and smoked fillets of Atlantic salmon, Salmo salar, fed high-energy diets

Atlantic salmon, Salmo salar , were fed four levels of dietary fat (256, 308, 346 and 389 g kg⁻¹ of diet) for 138 days, with the purpose of studying quality characteristics in raw and smoked fish fillets. Dietary fat levels up to 346 g kg⁻¹ resulted in increased fat content of the raw fillets. The dietary fat levels had a less systematic effect on perceived fatness of the smoked fillets and caused a trend towards better odour and flavour. The fat content of raw fillets was significantly ( P ≤ 0.05) correlated to lower smoke odour, greater rancid flavour, fatness, and a yellower hue of the smoked fillets. Astaxanthin levels of the raw fillets varied between 6 and 11 mg kg⁻¹ of fillet and were significantly ( P ≤ 0.05) correlated with greater intensity of smoke odour, lower off-odour, and less whiteness, greater colour intensity and a redder hue of the smoked fish. It is proposed that salmon fillets can be graded according to weight, fat content and colour values prior to smoking to obtain more standardized quality characteristics of the final product after processing.     

微波高压快速消解-紫外分光光度法测定南阳彩色小麦中的微量元素硒

以南阳灰麦、紫麦、蓝麦为材料,采用微波高压快速消解-紫外分光光度法测定了样品中微量元素硒的含量。结果表明:南阳彩色小麦中硒含量为13.37~21.95 mg/kg(干基),3ε32为1.4×104,标准曲线的相关系数r为0.999 7,加标回收率为100.6%~105.7%,RSD为4.4%,因此该法具有灵敏度高、稳定性好、工作曲线线性关系好的显著优点,结果令人满意。     

约互合成系猪Ag—NORs的遗传特征及其与毛色相关规律的研究

本试验利用染色体银染技术，对纯隐性黑色互助猪，纯显性白色约克夏及其杂交一代，杂交二代和杂交三代的体细胞分别进行核仁区染色，并对结果进行统计分析，结果表明，猪的Ag-NORs平均数与毛色之间具有极强的正相关(r=0.945）。     

Influence of Soil Drought on Plant Growth, Assimilation and Dissimilation of CO2 and Accumulation of Photosynthates in Field Bean (Vicia faba L. minor) During Pod Formation and Rapid Pod Growth

Field bean planes cultivar Nadwiślański were submitted to soil drought (30 % of field soil water capacity) for 5 days at the stage of pod formation (A) and of rapid pod growth (B) and then exposed for 20 minutes to ¹⁴CO₂. Radioactivity of leaves, stems, roots, and pods or pod shells and seeds was measured 1, 5, 24 and 48 hours after exposition.
In both stages soil drought reduced by about five times total CO₂ assimilation, mainly owing to lower activity of the photosynthetic apparatus and also, though less so, to reduced leaf growth. Photosynthetic activity referred to the dry weight of the leaves dropped to 22-35% of controls. Accumulation of photosynthetates in generative organs was much less depressed than ¹⁴CO₂ assimilation. 48 hours after exposition to ¹⁴CO₂ of drought treated plants, the contents of ¹⁴C of pods in phase A, and seeds in phase B, amounted to respectively 24% and 36% of assimilated ¹⁴C and equalled 91.5% and 74% of the corresponding values for controls.
The progressive decline of radioactivity in leaves and stems after ¹⁴CO₂ exposition was distinctly correlated to the rise of radioactivity of generative organs both in soil drought treated plants and in controls. Slightly lower values of correlation coefficients in drought treated plants may indicate impairment under drought conditions of synchronization in processes of unloading and accumulation of assimilates.
In plants drought treated in phase A the ability to dissimilate ¹⁴C was reduced to about 59% of that in controls, but when drought was applied in phase B, dissimilation rate was about three times as high.     

不同日粮对蛋黄色泽与蛋品品质的影响

通过基础日粮中添加饲喂玉米蛋白粉、芝麻油渣对蛋黄色泽沉积和蛋品品质的影响观察，结果发现，玉米蛋白粉、芝麻油渣部分替代黄玉米，均可起到色素在蛋黄中的沉积，且作用效果较好，试验各组与对照组比较，产蛋率、产蛋量、体重、蛋品品质及试验组组间差异均不显著；色素沉积以玉米蛋白粉和玉米蛋白粉加芝麻油渣呈现明显。