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991.
The influence was studied of intravenous application of colloid carbon to ten dairy cows of Bohemian Spotted breed in the seventh to eighth months of gravidity, as exerted on the health condition of mammary glands and on milk yield in the subsequent lactation. The cure consisted of three i. v. installations in 72-hour intervals; one dose contained 150 mg carbon in 20 ml of 20% glucose. No adverse by-effects were observed in the course of application and after it. During the subsequent lactation period (nine months) the test cows exhibited a better health condition of mammary glands if compared with the control group (ten dairy cows). In the test group no case was recorded of the clinical form of mastitis while in the control group one case of acute mastitis and two cases of chronic mastitis occurred. S. agalactiae was not isolated at all in the test group while in the control group it was isolated in two cows. S. aureus was also isolated more times (in 32 cases) in the control cows than in the test ones (in 27 cases). A higher average counts of cells in udder-quarter milk samples were found in the test group only at the onset of lactation (from the third month after calving), the average counts of cells over the whole period under study were however lower in the test group (1 380 000 per ml) than in the control group (1 234 000 per ml). The average daily milk yield per cow in the test group exceeded the average milk production in the control group in the period of study. An increase by 1.630 1 as compared with the untreated cow was observed in the average milk yield. It has been demonstrated by the results that by the intravenous instillation of colloid carbon nonspecific natural defensive mechanisms of dairy cows, mainly leucocytes, are stimulated, which enhanced the cell readiness to react to infectious process (mastitis) and overall injury of the organism (sepsis).  相似文献   
992.
An indirect enzyme-linked immunosorbent assay (ELISA) with unpurified Brucella melitensis smooth lipopolysaccharide (S-LPS) as antigen was evaluated for the serological diagnosis of B. melitensis infection in sheep in comparison with the Rose Bengal (RB), complement fixation (CF), radial immunodiffusion (RID), microplate agglutination (MA) and rivanol agglutination (RIV) tests. Tests RB and CF detected as positive each of the 77 sera from B. melitensis-infected animals tested, the RID (74), MA (76) and the RIV (72) were less sensitive. However, all tests compared were negative when 77 sera from Brucella-free rams were tested. While subcutaneous Rev 1 vaccination induced high response levels in any of the tests, low level responses were obtained upon conjunctival vaccination, particularly in ELISA and RID tests.  相似文献   
993.
Several analytical expressions have been proposed as models of weight versus time to describe growth but these have not been completely satisfactory. Some of them represent a good adjustment for only a part of the growth process; others have parameters of little biological significance or not enough practical interpretation. Some also involve troublesome numerical work, or do not have enough flexibility to accommodate exceptional cases.In this study, a simple flexible and analytical expression with biologically significant parameters is presented. In the authors' opinion this expression eliminates many of the deficiencies mentioned above.The proposed expression is validated with data available in the literature. Cases were selected and used to show the adequacy of the expression for adjusting quantitative variations between and within species.  相似文献   
994.
995.
In the oestral and anoestral periods, 129 ewes of the Slovak Merino breed were treated with different doses of the stimulants PMSG, PGF2 alpha, HCG, SG and FSH after synchronization by means of Ageline tampons. In the anoestral period, PMSG doses of 750 and 1000 i. u. were found to increase the number of tertiary follicles from 12.3 to 17.2 and 18.6, whereas the dose of 1500 i. u. was found to reduce this number from 18.6 to 13.5. PGF2 alpha increases the average number of tertiary follicles from 12.3 to 22.2 and when it is combined with 750 i. u. PMSG, the increase is to 29.3 tertiary follicles. At higher PMSG doses the ratio of atretic (A) to non-atretic (N) tertiary follicles rose and the number of ovulations increased from 2.5 to 4.0. After synchronization with Ageline and administration of PMSG at the doses of 750 and 1000 i. u., the number of tertiary follicles increased from 16.0 to 18.4 and the number of ovulations from 3.1 to 5.7; the number of atretic tertiary follicles showed no change. In the oestral period, the dose of 1000 i. u. PMSG administered after PGF2 alpha reduced the number of tertiary follicles from 18.9 to 14.5 and increased the number of ovulation from 1.6 to 2.6; an increase was also recorded in the number of atretic tertiary follicles.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
Eleven test and control bullocks of the Bohemian Spotted breed were studied for the effect of cysticercosis and their treatment with praziquantel on the properties of meat and fat. As found, the disease affected the composition of meat and fat and some of the studied characteristics and technological properties of meat. Although the measles disappeared after treatment, they were not resorbed. Therefore, irrespective of the worsened meat quality, the meat and organs of such animals cannot be evaluated in any other way but according to the valid veterinary regulations.  相似文献   
997.
Broilers with feather follicle inflammation and birds free of this disorder were selected from the broiler chickens kept on plastic (bralen-)coated metallic slats. Both groups of broilers were killed on a sanitary slaughter line and the samples of breast and thigh muscles were analyzed for the basic composition and characteristics of the metabolism of nitrogenous and lipidic components. The content of individual amino acids in the muscles and the proportion of fatty acids in the intramuscular fat of broilers were determined for the evaluation of nutritive value. The samples of the affected spots of skin and samples of organs (liver) were subjected to microbiological examination. The resultant finding represented the common mesophilous microflora. No substantial statistically significant differences in chemical characteristics were found between the two groups. It follows from the results that the inflammation of feather follicles is a local skin disorder with no effect on the quality of the meat.  相似文献   
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