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411.
Contents: Different trials were performed on Zebu blood samples, kept under variable experimental conditions, to determine the extent of the degradation of measurable progesterone. Blood samples were collected and combined with different anticoagulants (heparin, EDTA or citrate) and kept 30 minutes, 3 h and 18 h at 20° C to determine if there was an anticoagulant effect. Progesterone concentrations declined rapidly (P <0.05) regardless of anticoagulant used. Different samples of uncentrifuged whole blood to which lithium heparine had been added and unseparated clotted blood were held at 3° C, 20° C, 35° C for 0, 3, 6, 12 and 18 h to determine the effect of time and temperature. Progesterone fell (P < 0.05) with time at all incubation temperatures in all cases. Lithium heparine whole blood (control) was kept for 0, 6, 18 h and for 3, 5, 7 days before centrifugation and compared to samples to which 5 mg/ml sodium azide was added, all kept at 22–25° C. The addition of sodium azide resulted in the maintainance of significantly greater (P < 0.001) progesterone concentrations than in the control although in both, progesterone declined significantly (P < 0.05) as early as 6 h. Three to 7 days after collection, however, there was a reappearance of progesterone to the point that no difference (P > 0.05) resulted with initial values in the sodium azide treated samples. Inhalt: Abnahme des Progesterongehalts in Zebu-Blutproben unter verschiedenen experimentellen Bedingungen In unterschiedlich vorbehandelten Blutproben des Zeburindes wurde die Abbaurate des meβbaren Progesterons bestimmt. Die Blutproben wurden mit verschiedenen Antikoagulantien (Heparin, EDTA, Citrat) versetzt und für 30 Minuten, 3 Stunden oder 18 Stunden bei 20° C inkubiert. DerProgesterongehalt nahm unabhangig vom jeweiligen Antikoagulans rapide ab (P<0.05). Heparinisiertes Vollblut und unbehandeltes Vollblut wurden 0, 3, 6, 12 und 18 Stunden bei 3° C, 20° C und 35° C aufbewahrt. Der Progesterongehalt nahm injedem Falle unabhängig volt der Temperatur mit der Zeit ab (P < 0.05). Heparinisiertes Vollblut (Kontrolle) und Vollblut, das mit 5 mglml Natrium Azid versetzt worden war, wurden vor dem Zentrifugieren 0, 6 und 18 Stunden, sowie 3, 5 und 7 Tage bei 22 -25° C aufbewahrt. In beiden Gruppen nahm der Progesterongehalt schon nach 6 Stunden signifikant ab (P < 0.05). Jedoch 3 bis 7 Tage nach der Blutentnahme war der gemessene Progesteronwert wieder auf ein höheres Niveau angestiegen, so daβ es sich in den mit Natrium Azid behandelten Blutproben nicht mehr significant von den Anfangswerten unterschied (P > 0.05).  相似文献   
412.
The effect of feeding mink manure to pigs and the utilization of its protein and mineral content was studied by blood analyses. Individual variation was large, and the differences between groups were small. Growth of the animals had a significant effect on the levels of several blood components. Judging from the blood analyses, mink manure feeding did not have any harmful effects on the health of the pigs, and the differences to normal feeding were small.  相似文献   
413.
Paternity tests in multisired beef herds by blood grouping   总被引:1,自引:0,他引:1  
The number of offspring sired by individual bulls in multisired beef herds was determined by blood grouping. Six series of tests, each having from 3 to 18 bulls as possible sires,, yielded from 35 to 114 dam-offspring pairs. The paternity was established for 45 to 90 % of the calves tested in each series. The rest were cases with either more than 1 bull not being excluded as the possible sire, or all bulls excluded from being the sire. The causes for the non-established paternities are discussed. Highly significant differences were found in the number of offspring sired by each bull. In each series, bulls ranking in the top third of the siring order sired 65–100 % of the calves with established paternities. Since a minority of the bulls sired the majority of the calf-crop, the generally recomended number of bulls for herds on the range can perhaps be reduced.  相似文献   
414.
Running exercise in pigs results in an elevation of lactic acid in blood. This elevation in blood lactate does not occur in physically conditioned pigs. Activities of succinic dehydrogenase, fructose-l,6-diphosphate aldolase, lactate dehydrogenase and creatine Phosphokinase as well as the myoglobin content were determined in m. gastrocnemius from 6 ergometer-trained and 4 untrained pigs. The succinic dehydrogenase and myoglobin contents were significantly higher (P<0.01) in trained animals, whereas no changes were noted in the aldolase and creatine Phosphokinase contents. The lactate dehydrogenase showed somewhat reduced levels in the trained pigs. This was accompanied by an increased H/M subunit ratio. The results provide evidence for an increase in the maximal aerobic metabolism in trained pigs and that trained pigs to a higher extent can rely on an aerobic energy metabolism during running exercise.  相似文献   
415.
Outbred albino laboratory mice were exposed to 50 p.p.m. and 500 p.p.m. vinyl chloride by inhalation 6 hrs./day, 5 days/week during 52 and 26 weeks, respectively. Pathologic examination showed the presence of histologically benign alveologenic lung adenomas, haem-angiosarcomas in fat tissue as well as a few benign and malignant tumours at various sites. Only one liver haemangiosarcoma was noted. All animals exposed to 500 p.p.m. developed tumours; 71 % of the animals given 50 p.p.m. were tumour bearing. The frequency of all tumours, number of tumour foci and size of foci in both groups suggest a dose-dependent carcinogenic effect of vinyl chloride. Haemocoelia due to blood vessel rupture was a common cause of death. Telangiectasis of the liver was also observed in a few animals. The role of fat tissue as well as blood vessel involvement in the pathology of vinyl chloride is discussed.  相似文献   
416.
Mononuclear cells isolated from thymus, spleen and cord blood of pig fetuses ranging in age from 48 to 112 days were examined for the presence of sheep red blood cell rosette-forming cells (SRBC-RFC). After an initial increase from 77 % (mean) at 48 days of gestation to 88 % at 60 days, the proportion of SRBC-RFC in thymus remained constant throughout the gestational period. In spleen and cord blood, the proportion of SRBC-RFC increased with age, from occasional rosette-forming cells at 48 days of gestation to 21 % and 30 %, respectively, at 112 days. The demonstrated development of SRBC-RFC in the thymus, spleen and cord blood is considered to reflect the ontogeny of T cells in these fetal pig tissues.  相似文献   
417.
Recently an inherited vitamin G deficiency in the pigs presumably based on an autosomal recessive gene was decribed* Homozygotes are in contrast to heterozygotes and normal pigs unable to synthesize ascorbic acid. In an experiment comprising 3 littermate pigs, 2 homozygous and 1 heterozygous for the vitamin C deficiency gene, the influence of ascorbic acid depletion, and repletion on mitogen stimulation of peripheral blood lymphocytes was studied. Ascorbic acid depletion of the vitamin C dependent pigs resulted in a rapid decline in plasma ascorbic acid. Response of lymphocytes to stimular tion with Concanavalin A (Con A) and phytohemagglutinin M (PHA) decreased more slowly reaching a minimum, which coincidedi with the occurrence of the first clinical symptoms of scurvy. Following resupplementation with vitamin C the plasma content of ascorbic acid rapidly returned to normal, while the lymphocyte response to Con A and PHA stimulation only gradually approached the initial values. The repletion with ascorbic acid caused a transitory increase in the response to pokeweed mitogen (PWM) stimulation. The significance of these findings in relation to the cellular immune system in normal pigs is discussed.  相似文献   
418.
Blood and saliva samples were taken from groups of pigs maintained in intensive conditions. Multiple samples were taken from two unrestrained pregnant sows fitted with jugular cannulae. Single samples were taken from groups (mixed gilts and entire males; 70–90 kg) which were lightly exercised (7) or restrained (12). The rate of salivary secretion was low and collection of adequate samples took 5 min; in a number of pigs no saliva could be obtained.In order to stimulate salivary secretion, pigs (70–80 kg) were injected with pilocarpine nitrate (25 mg, subcutaneous) which produced a copious flow of saliva persisting for at least 15 min.Resting sows had higher mean levels of cortisol in plasma, ultrafiltrate and saliva than the other groups, which did not differ from each other. Within the pilocarpine group, males had a higher ultrafiltrate level of cortisol than females. In most instances salivary cortisol was significantly greater than ultrafiltrate cortisol.Ultrafiltrate and plasma cortisol were highly correlated (r=0.883) but this correlation was low in the presence of pilocarpine (r=0.260). Salivary cortisol was poorly correlated with either plasma (r=0.167) or ultrafiltrate cortisol (r=0.278) and the correlation with plasma was even lower following the administration of pilocarpine (r=0.086).It was concluded that salivary estimates of cortisol in the pig were not usefully correlated with levels of ultrafiltrate (free) cortisol.  相似文献   
419.
饲喂IgG对仔猪血液生化指标和生产性能的影响   总被引:3,自引:0,他引:3  
试验分两批选用 12 0 ,6 0头大白仔猪 ,出生 2 4h之内饲喂不同剂量的免疫球蛋白制剂 0 ,4 80 ,96 0mg ,均吮食初乳。于仔猪 5 ,10 ,15日龄前腔静脉采血 ,测定血清总蛋白、血清IgG、血清碱性磷酸酶和血红蛋白含量 ,并测定仔猪断奶时增重 ,哺乳前、后期平均日增重。结果表明 :饲喂不同水平的IgG ,仔猪 5 ,10日龄血清总蛋白、血清碱性磷酸酶活性和血红蛋白含量均显著高于对照组 (P <0 0 5 )。饲喂高水平IgG(96 0mg)的仔猪 ,5日龄血清IgG水平显著高于对照组 (P <0 0 5 )。哺乳前期 (0~ 15日龄 )各处理组仔猪平均日增重显著高对照组 (P <0 0 5 ) ,断奶时增重也显著高于对照组 (P <0 0 5 )。  相似文献   
420.
捻转血矛线虫离体培养的研究   总被引:2,自引:0,他引:2  
本实验研究了:(1)三种人工合成培养基:M199、NCTC109、F_(12);(2)小牛脱纤维蛋白血(以下简称小牛脱纤血)、Filde’s试剂,Bovine hemin;(3)pH值等几种因素对离体培养中捻转血矛线虫(Haemonchou contortus)L_3发育至L_4的影响。结果表明:(1)在相同条件下,NCTC109和M199培养系中的L_3可发育至L_4晚期,F_(12)中L_3只发育至L_4早期;三种培养系中L_3发育至L_4的虫体数占存活虫体数的90%以上,以NCTC109中的发育率为最高,达100%。(2)小牛脱纤血、Filde’s试剂和Bovine hemin对L_3发育至L_4均有促进作用,虫体的存活率明显提高,晚四期幼虫的存活时间延长;小牛脱纤血和Filde’s试剂可使L_3至晚L_4的时间缩短。(3)pH 5.8~6.2时,L_3发育至L_4;速度明显减慢,发育率不到50%;pH 6.6~6.8时,L_3发育至L_4的同步性及发育率明显提高,以pH6.6为最佳。  相似文献   
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