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131.
G Fehér 《Anatomia, histologia, embryologia》1988,17(2):107-120
The process of hatching in goose and duck From the 4th to the 16th or 17th day of incubation the wall of duck and goose amnion actively, peristaltically and rythmically contracts 20 and 12 times per minute, respectively. A pause of five seconds follows each 5th contraction. The contractions also passively influence the yolk sac, the allantois and the air cell. The M. complexus grows more than four times its original size during the 24th to the 27th day of incubation. It contains two kinds of myosin: neonatal myosin (200,000 Dalton) and adult myosin (480,000 Dalton). The amounts of the adult myosin present at the time of hatching is about 15 times the amount in the skeletal muscles. The process of hatching is described in the duck and goose. 相似文献
132.
The effect of the addition of zeolite to pig feed ration was studied in the cage rearing system under production conditions. Zeolite was mixed in the COS I and COS II feed mixtures directly in the feed plant, the mixing ratio being 100 kg feed mixture + 5 kg zeolite. The feed mixture was administered in granular form ad libitum. The test group had 648 weanlings and the control group 674 weanlings; the piglets, kept in two-story cages in four sections, were arranged so that the test group could be a mirror-like reflection of the control group. The trial lasted 45 days. The piglets given the fortified feed ration had daily weight gains higher by 0.017 kg and feed consumption lower by 0.234 kg per 1 kg of gain, as compared with the control animals. The costs of the feed ration required for producing a kilogram of gain were 8.55 Cz. crowns in the zeolite group and 9.422 crowns in the control group. 相似文献
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135.
We studied the influence of the three main nutritive components of milk - saccharides, fat and amino acids - on milk intake in suckling lambs and on the role of insulin as a key metabolic hormone for the regulation of milk intake. The intake was slowed down after p.o. administration of milk fat (p less than 0.05), after i. v. administration of methionine (p less than 0.001) and after p. o. administration of glucose, lactose (p less than 0.01, p less than 0.001) and sorbitol (p less than 0.001). After i. v. administration of glycerol, lysine, threonine, arginine, glucose, and i. v. and p. o. administration of galactose the intake of milk did not change significantly (p greater than 0.05). The findings indicate that the short-time regulation of milk intake in suckling ruminant animals is not subjected to the specific effect of some of the milk components. Regarding the metabolic effects, the problem concerns the speed of resorption of easily metabolizable sources of energy from the digestive system to the liver and to the whole body. Neutral Zn-insulin administered intraperitoneally at a dose of 4 U X kg-1 increased the milk intake (p less than 0.01, p less than 0.001), in 8 to 22 hours after the administration only when the animals were on the low-fat milk diet (5.9%-11% fat in dry matter). We assume that the long-range hyperphagy can be related mainly with the fast metabolizing of energy-rich substances (glucose) into the body stores (glycogen, fat) accompanied by subsequent hormonal changes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
136.
J Struháriková P Slivka L Slanina D Soták A Elbertová P Polahár 《Veterinární medicína》1989,34(4):193-202
A comparative trial was conducted with the oral administration of zinc sulphate to pregnant cows and heifers aimed at influencing the selected metabolic parameters in the dam-calf line. The total daily ZnSO4.7H2O dose of 3 g (680 mg Zn++) was given to dry standing cows and heifers for 35 days on an average (15-65) before the expected date of calving. The breeding conditions in the stock were problematic: losses of calves suffered in the last half-a-year period were higher than 30% of born calves; the main causes of this high mortality were coli-septicaemia and coli-enteritis. As compared with the eight control animals, the experimental cows and heifers (12 head) exhibited a transient increase in zincaemia, followed by a tendency to proteinaemia; aspartate aminotransferase activity increased, total immunoglobulins remained unchanged, and decreases were recorded in the activities of alanine aminotransferase, alkaline phosphatase, creatine phosphokinase and aldolase. On the other hand, the concentration of total bilirubin tended to increase. In 77% of the cows and first-calvers of the experimental group the quality of colostrum complied with the standard; in the case of the control animals this proportion was 83%. Significant zincaemia occurred in the calves of the experimental cows between the first and 14th day of their age; no differences from the control calves were recorded in immunoglobulinaemia, proteinaemia, albuminaemia and in the activities of alanine aminotransferase and creatine phosphokinase. On the other hand, aspartate aminotransferase activity tended to grow and alkaline phosphatase activity tended to sink. Neonatal hyperbilirubinaemia disappeared within the first 14 days of age in both the experimental and the control calves. The results failed to show clearly that the intention to increase the values of the studied parameters of immunopoiesis was met. 相似文献
137.
138.
We evaluated the ovaries of 34 cows cross-bred of the Slovak Pied and Lowland Black-pied breeds which were culled and intended for slaughter during the winter type of feed rations. For superovulation treatment we used PMSG in the preparation Serum Gonadotropin (Bioveta, Nat. Ent., Ivanovice na Hané) and cloprostenol in the preparation Oestrophan inj. Spofa. We weighed the excised ovaries, fixed them in formalin 10% and made a quantitative evaluation of the surface follicles and differentiated them into recruited and selected or dominant follicles. We determined the concentration of 17 beta-estradiol and testosterone with the aid of the 3H RIA set from the firm Sorin after extraction by diethylether with separation of free and bound hormone with active charcoal. 72 hours after the giving of cloprostenol 43% reacted positively to superovulation treatment and after seven days a 50% positive response was recorded. After a dose of 2000 i. u. of PMSG (n = 6) embryo was obtained, whereas after 3000 i. u. of PMSG (n = 8) we flushed out eight embryos, of which four zygotes were suitable for transfer. After a higher dosage of PMSG there was an increase in the average weight of the ovaries, in right-hand ovaries significantly with P less than 0.05. After super-ovulation treatment the concentration of 17 beta-estradiol (E2) in the follicular fluid from follicles seven days after insemination was found to be so low as to be below the limit of detection, with the exception of four samples (mean = 8.60 nmol.l-1). The greatest concentration of E2 was from animals (n = 5) 72 hours after the giving of cloprostenol--1099.61 nmol.l-1) of follicular fluid. The concentration of testosterone was lower in the follicles of untreated cows in the follicular phase (mean = 5.92 nmol.l-1) compared with the follicles of super-ovulated animals the seventh day after insemination (mean = 14.12 nmol.l-1). The number of recruited and especially selected surface antral follicles 72 hours (n = 7) after the giving of cloprostenol and seven days (n = 8) after insemination was significantly higher in the group of brood cows reacting positively to superovulation in comparison with the animals which did not respond. It appears that the simultaneous monitoring of hormonal and morphological changes in the follicular system will help in objectivising the evaluation of the functional activity of stimulated follicles. 相似文献
139.
140.
L.G. Paisley L. Vraa-Andersen L. Dybkjr K. Mller G. Christensen J. Mousing J. F. Agger 《Acta veterinaria Scandinavica》1993,34(4):331
A total of 578 slaughter pigs from 2 Danish conventional farrow-to-finish operations (Herds a and B) were followed from an age of 14 days to slaughter. Pigs were weighed at 3 weeks intervals and at slaughter and extended post mortem examination of the plucks was done. Regression models with second and third order interaction terms demonstrated that Mycoplasma-like pneumonia, complicated pneumonia, anterio-ventral pleuritis, pericarditis, fissures and atrophic rhinitis, separately and through interactions with other lesions, significantly reduced mean daily gains during specific intervals of the growth period in 2 conventional swine herds. It is likely that the periods of reduced growth reflect the times when the diseases were in the acute and early recovery stages. Maximum estimated reductions in daily gains associated with the combined lesions were 82 grams and 283 grams during the interval 120-140 days in Herds A and B, respectively. Although dorso-caudal pleuritis and parietal pleuritis had minor negative effects during 2 intervals neither had a significant adverse effect on total growth rate in either herd (Paisley et al. 1993). R2 values for the regression models were less than 0.27 showing that the lesions present at slaughter explained less than 27% of the variation in herd mean daily gains during any interval. 相似文献