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981.
982.
983.
Fiber fermentation using the in situ bag technique was studied in a hay-fed cow. Entry of fine particles into bags of varying pore size, the effect of sample size, rumen contractions, bag porosity and rumen contraction (bags suspended in vitro or in situ) and obstruction of liquid flow through the bag cloth were investigated (Exp. 1). In Exp. 2 fiber degradation in vitro and in situ with 5- and 37-micron pore size bags was measured utilizing six fistulated heifers (four large: 610 kg and two small: 243 kg), two sheep and two goats (30 kg), three ponies (130 kg) and four rabbits (3.2 kg). Degradation rate (k) and indigestible fiber (B) were determined after curve fitting. Lag of fermentation was also calculated. Results of Exp. 1 showed that plant fiber containing approximately 50% lignin and 2.9% N entered even 20-micron pores, that rumen contractions increased fiber disappearance and that obstructing liquid exchange limited fermentation. Results of Exp. 2 showed lower fiber residues for 37-micron than for 5-micron pore size bags and that in situ method, time and species were highly significant (P less than .0001). All model factors differed significantly among species (P less than .05), but not among the three methods. Lag approached significance for methods (P = .07), but not for species. In situ measurements (37-micron) resulted in the following values for k (h-1), B (%) and lag (h): large heifers .040, 39 and -1; small heifers .025, 39 and 0; sheep-goats .051, 42 and 2; ponies .030, 59 and -5 and rabbits .107, 85 and 3. 相似文献
984.
985.
Ch Damdinsurén 《Archiv fuer experimentelle veterinaermedizin》1989,43(5):763-767
Mycoplasmas were isolated from yak calves in Mongolia, the 1st experience worldwide with this species. They were also isolated from pathologically affected sheep and goat lambs. The disease was experimentally reproduced in yak calves as well as in sheep and goat lambs. Clinical manifestations were identical with those recordable from animals with spontaneous outbreak of the disease. This had been for the 1 time ever that a therapy was tested on animals with mycoplasmosis, using water with addition of oligodynamic silver. Something between 95 and 100% of all patients were clinically cured. The experimental vaccine involved was found to offer protection against mycoplasmosis to sheep and goat lambs. Damage association with mycoplasmosis was found to occur 1st in liver, spleen, and lymph nodes and to be subsequently proliferated to lung and other organs. Respiratory mycoplasmosis is the common definition used at present but is not in conformity with the pathological processes involved, as the major role is played by liver damage. Mycoplasmosis in these 3 species, therefore, should better be named mycoplasmosis bovi hepatica. 相似文献
986.
The Bulbus oculi of 25 buzzards of both sexes and of nearly the same age and weight, was examined with regard to its gross anatomy, strucutre, ultrastructure and size. The volume of the eyeball is of 9.5 cm3. In the Anulus sclerae there are about a dozen of cartilagineous plates, and in the Corpus ciliare there can be found between 112 and 115 Processus ciliares. The muscle of Müller was not observed. Morphological details of the Pecten are given and its functional significance is discussed. 相似文献
987.
988.
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990.