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941.
日粮类型对猪肉营养和品质的影响 总被引:1,自引:0,他引:1
在日粮粗蛋白、能量、钙、磷水平相近的情况下,蛋白饲料种类及微量元素Fe、Cu添加水平不同,所饲喂猪只肉质与肉食营养不相一致。根据本试验结果,“豆饼+鱼粉”型日粮在高剂量Fe、Cu的协同作用下有利于促进肌肉的生长和饲料氨基酸向肌肉氨基酸的转化,而“棉籽饼+菜籽饼”型日粮可期望获得较好的肉质。肌肉Fe、Cu、Zn、Mn沉积受饲料影响不明显。 相似文献
942.
943.
The main purpose of the present study was to investigate whether boar seminal plasma affects the transport of spermatozoa in the genital tract of oestrous pigs or not, with special reference to the sperm transport into the oviducts. Altogether 17 gilts were used in three experiments.Experiment I. In nine gilts one uterine horn was injected surgically with 1010 spermatozoa suspended in seminal plasma and the other uterine horn with 1010 spermatozoa suspended in TESNaK-glucose buffer solution. The sperm deposition was performed under general anaesthesia. The gilts were slaughtered 1–2 or 4–6 h after insemination. The genital tract was removed and the numbers of spermatozoa determined in oviducts and in uterine horns.Experiment II. The insemination doses were prepared exactly as in Experiment I. Approx. 24 h before insemination Polyvinylchloride cannulas were inserted into the uterine lumen of the horns, drawn via the midventral incision at linea alba subcutaneously to cutaneous incisions ventral to the vulva opening. One cannula was placed in each uterine horn. At standing heat the insemination doses were slowly injected through the cannulas. The gilts were slaughtered 1 h after insemination and the numbers of spermatozoa within the genital tract were counted.Experiment III. In three gilts under general anaesthesia the uterine horns were ligated 10 cm from the uterotubal junction. The semen doses (containing 2 × 109 spermatozoa), prepared as in Experiment I, were deposited into the uterine horns anterior to the ligatures through a cannula. The gilts were slaughtered 1 h after insemination, and the numbers of spermatozoa within the oviducts and ligated part of the uterine horns were counted.In all three experiments more spermatozoa were, on average, recovered in the oviducts connected to uterine horns inseminated with spermatozoa suspended in seminal plasma. In Experiments I andII this was the case for 10 of 14 gilts and in Experiment III for all the three gilts. It is therefore suggested that boar seminal plasma pro¬motes sperm transport into the oviduct of oestrous pigs. The back¬ground mechanism for this is discussed. 相似文献
944.
This paper reports the results of a 2 × 2 factorial experiment on bush snap beans ‘Oregon 1604’. The treatments were 2 contrasted irrigation regimes and 2 contrasted plant densities, and were applied in 1978 and repeated in 1979. Data were collected on the number of flowers and pods, and pod size, at each node of the terminal inflorescence (6-T) of the main stem, and at each node of the oldest inflorescence (2-A) at Node 2. High and low plant densities were 45 and 18 plants m?2 in 1978 and 54 and 33 plants m?2 in 1979. High temperatures, frequently above 32°C, prevailed during bloom and pod development in 1978, but for the most part occurred only during the week prior to bloom in 1979. Inflorescences 6-T and 2-A usually formed 4 and 3 RN's, respectively, in 1978 and 3 and 2 RN's in 1979. The flowers at the proximal nodes of each inflorescence all opened within a few days of one another (duration of flowering at proximal nodes between 3 and 5 days); the flowering-periods of adjacent nodes overlapped, and the flowering period increased acropetally within the inflorescence (duration of flowering at distal nodes between 7 and 13 days). In general, number of flowers, pods formed, pods harvested and percent set decreased acropetally within each inflorescence. The rate of acropetal decline was lessened by high irrigation or low plant density. In both years, high irrigation increased the percent set of all RN's of the 2-A inflorescences, but few other consistent effects between years were observed. The 2 most proximal RN's together produced 93% or more of the yield of each inflorescence. High irrigation significantly increased the total number of pods harvested from these RN's of inflorescences 6-T and 2-A, and low density had a similar effect on 2-A. 相似文献
945.
At concentrations near 2 × 10?4M, barban, chlorpropham, and phenmedipham are inhibitors of the electron transfer in potato and mung bean mitochondria. The inhibition seems to be localized in the flavoprotein region. It affects preferentially the exogenous NADH dehydrogenation, in potato mitochondria (I50, 10?4M). Succinate dehydrogenation is less inhibited. At noninhibiting concentrations, the studied carbamates cannot uncouple the oxidative phosphorylations. Photosynthesis is completely inhibited by 2.10?7M phenmedipham, 5 × 10?5M barban, and 2 × 10?4M chlorpropham. The inhibition takes place at the PS II level. Moreover, barban and chlorpropham are uncouplers of the photophosphorylations for concentrations between 5 × 10?5 and 5 × 10?4M. The effects observed on mitochondrial respiration can also be found on respiration of Acer cultured cells. The effects on isolated chloroplast photosynthesis are also observed for slightly higher concentrations on cultured Chlorella and on pea and oat leaf fragments. 相似文献
946.
Sera from adult cattle with fluke-infected and normal livers were analyzed for γ-GT and AspAT activities. The analyses revealed no significant increases in either γ-GT or AspAT values of the animals with fascioliasis as compared with the non-infected animals. The advanced chronic stage of the infection characterized by hepatic fibrosis, limited injury of parenchyma and low fluke burdens may explain the lack of enzymatic increase. 相似文献
947.
948.
The relationship between some skin characteristics and hemoglobin values during the growth period were statistically examined in standard male minks. Significant correlations) (P < 0.05–0.001) were found between the hemoglobin concentrations determined at 3 points during the growth period (in July, August and November) and the density and colour of underfur, and skin length, respectively. According to the study even the early hemoglobin values in July and August have a significant influence on the size and quality of the pelt. Mink kits with low hemoglobin values are liable to develop a winter fur coat with defective pigmentation and hair structure of the underfur. Anemic minks develop the most extreme stage of the pigmentation defect and these so-called cotton fur skins have little value in the fur garment industry. When these abnormal hemoglobin values are recognized at an early stage, cotton fur skins may be avoided, and larger skins of better quality may be produced. 相似文献
949.
Gunner Hi Srensen 《Acta veterinaria Scandinavica》1980,21(3):438
The growth and the toxin (i.e. hemolysin) producing capacity of Corynebacterium pyogenes were studied in monocultures and in co-cultures with 1 or more of the organisms frequently accompanying it in summer mastitis in cattle (Peptococcus indolicus, Stuart-Schwan cocci, Bacteroides melaninogenicus subsp. levii, Fusobacterium necrophorum and Streptococcus dysgalactiae) or with organisms seldom associated with summer mastitis (Streptococcus uberis, Streptococcus agalactiae, non-toxic staphylococci and Escherichia coli).Pc. indolicus, and to some extent also Stuart-Schwan cocci, stimulated the growth as well as the hemolysin producing capacity of Gb. pyogenes (Table 1) while Str. dysgalactiae, Str. uberis, Str. agalactiae, E. coli and the majority of the staphylococci reduced these activities. Most F. necrophorum strains stimulated the growth, but not the hemolytic activity. With B. melaninogenicus the results were inconclusive.The effect of Pc. indolicus appeared to be associated with the production of a filterable factor (Tables 2 and 3).Mouse toxicity and hemolytic activity of culture filtrates were closely correlated (Table 4). 相似文献
950.
播期对油菜"两优586"生育、产量及抗性的影响 总被引:1,自引:1,他引:0
研究了播期对油菜"两优586"生育、产量及抗性的影响。结果表明:在江西宜春,"两优586"的最佳播期为10月8日,适宜播期为10月1日~10月15日,产量可达1792.50~1929.75kg/hm2,生育期适中(190d左右),单株有效角果数较多,为345个左右,且抗性较强,发病率低于15%,倒伏率低于10%。 相似文献