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991.
992.
993.
A Tanyola? W Meyer M Sa?lam A Ozer Z Ozan S Müftüo?lu R Schwarz 《DTW. Deutsche tier?rztliche Wochenschrift》1989,96(10):498-503
The study describes basic structural aspects of the integumental layers (epidermis, dermis, hypodermis) of the Turkish Angora goat. The results have been obtained by light- and electronmicroscopical methods. Central topics are measurements of layer thickness as related to annual season and life period, as well as typical criteria of integumental layer construction as connected with the hair cycle. Remarkable is a trimerous organization of the dermis and cyclic changes in the thickness of the stratum adiposum of the hypodermis. The findings are discussed with regard to comparable observations from other domestic mammals. 相似文献
994.
The effects of feeding two fibre-rich diets with contrasting solubility and a concentrated low dietary fibre on the rate of gastric emptying were examined in six gastric cannulated pregnant sows. Additionally, it was examined whether any effect could be related to the physico-chemical properties of digesta, i.e. viscosity and/or water binding capacity. The sows were fed each diet for one week in a 3 x 3 Latin Square design and the samples were taken in a randomised order 0.5, 1, 2, 3, 5 and 15.5 h after the morning meal. The stomach contents were evacuated through the gastric cannula once daily. The evacuated gastric digesta was quantified and a representative sample was taken to determine its viscosity, water binding capacity and its content of dry matter, dietary components and solid (Cr2O3) and liquid (polyethylene glycol) phase markers. The flow of liquid digesta was calculated as the difference between digesta and dry matter. Increasing the content of dietary fibre in the diet led to higher recovery of liquid digesta but did not have any significant effect on the gastric emptying of dry matter and dietary components. The effect of dietary fibre could not be attributed to the viscosity of the liquid phase of digesta but might be related to the ability of the increased gastric dietary fibre content to hold water. The stomach selectively retained the insoluble dietary fibre components most noticeably seen with the bran-supplemented diet where the concentration of insoluble NSP in digesta increased significantly from 2 hours and onward. 相似文献
995.
Consequences of nematode infections due to Haemonchus contortus are a serious constraint for the sheep industry worldwide. Development of anthelmintic resistance and increasing concern about the impact of anthelmintic use dictate the need of alternative control. Such an alternative is using the nematode trapping fungus Duddingtonia flagrans to reduce infective larvae levels on pasture. Two trials were conducted to determine the effect of D. flagrans in reducing infective larvae (predominantly H. contortus) in feces. The first trial determined the dose effect of D. flagrans in reducing infective larvae in feces. Eighteen ewes were dewormed to remove existing infections and randomly assigned to six treatment groups: 5 x 10(4), 1 x 10(5), 2.5 x 10(5), 5 x 10(5), 1 x 10(6) or no (control) spores of D. flagrans per kg of body weight mixed in their feed for 7 days. Fecal samples were collected daily from these and from infected donor ewes. Feces from individual-treated ewes were mixed with equal amounts of donor ewe feces, theoretically approximating oral dose spore concentrations of 2.5 x 10(4), 5 x 10(4), 1.25 x 10(5), 2.5 x 10(5), 5 x 10(5) and no spores, and were cultured. Across dosages and during the 7 days of fungus feeding, percent reduction of infective larvae ranged from 76.6 to 100.0%. The second trial determined the effect of D. flagrans at the dose of 10(5) spores per kg body weight on reducing infective larvae in feces from naturally infected lambs. Twenty lambs were randomly assigned to either treatment or control groups based on fecal egg count. Treatment lambs were fed spores mixed in feed for 7 days. Feces were collected daily and cultured. During the 7 days of fungus feeding, the percent reduction of infective larvae ranged from 82.8 to 99.7%. Results of these trials demonstrated that the nematode trapping fungus D. flagrans was highly effective in reducing infective larvae in sheep feces and should be considered as a biological control agent for integrated nematode control programs. 相似文献
996.
In this study, the effects of nitroscanate were investigated in naturally acquired Hymenolepis nana infections in rats and mice. The natural infection was determined by centrifugal flotation technique of faeces. The infected rats and mice were divided into two treatment and two control groups (N = 10). Nitroscanate at the dose of 50 mg/kg per day was given in the diet for 4 days. The rats and mice of treatment groups were necropsied on 7th day after the last treatment together with those of control groups. Following necrospsy, in the treatment group a geometric mean of 1.07 Hymenolepis nana were recovered out of ten mice, compared with 8.14 in the control group. In the rat treatment group no Hymenolepis nana were found in ten rats, while the control group showed a geometric mean of 6.23. Nitroscanate was found to be effective 100% and 86.8% at the treatment of H. nana infection in rats and mice respectively. 相似文献
997.
998.
The immunocytochemical localization of several matrix macromolecules, including collagen type II and proteoglycans, in the distal femoral articular-epiphyseal cartilage complex of 15 commercial pigs between the age of 6 and 18 weeks was studied. Early osteochondrotic lesions, i.e., chondronecrosis in the resting region of the growth cartilage, as well as extensions of necrotic cartilage into the subchondral bone, were present in all animals, except those 6 weeks old. A battery of antibodies were used for identification of macromolecules in the matrix at different stages of the disease. Chondrocyte involvement in the process could be studied by identifying the sequence of alterations in matrix macromolecules as the lesion developed. The immunostaining for aggrecan (large aggregating proteoglycans), cartilage oligomeric matrix protein, fibronectin, collagen type II, fibromodulin, and biglycan was more prominent in the areas of chondronecrosis, extending into the subchondral bone, than in the normal resting region. This altered pattern of matrix macromolecules resembled that of the matrix of the proliferative chondrocytes and suggests that the chondrocyte maturation had stopped in the proliferative zone. The matrix in the areas of chondronecrosis in the resting region resembled that in the normal resting region. Thus the chondronecrosis appears to have preceded alterations of the matrix composition. The antibody reactivity pattern was, however, altered in the matrix of the clustered chondrocytes in areas of chondronecrosis. Staining in these regions suggested a more prominent appearance of fibronectin and collagen type II than in the normal matrix of the resting region. These changes are suggestive of attempt to repair.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
A. F. M. Ekramul Haque A. Hamid M. T. Islam M. Mohiuddin 《Journal of Agronomy and Crop Science》1992,168(1):61-64
Effects of seedbed condition and seeding depth on the emergence and seedling vigour of upland rice was studied. Regardless of aggregate size distribution, seeds sown at 2 cm depth gave the maximum emergence rate (80-90 %) which was reduced to 47 % for sowing at 5 cm depth. Seeding at 10 cm depth caused total failure in emergence. When planted at 2 cm depth, aggregate size produced considerable variation in the speed of emergence but caused no significant differences in final emergence count. For seeds sown at 5 cm depth, seedbed with aggregate size < 2 mm resulted in poor emergence (12 %) while with aggregates > 8 mm reduced emergence by 34 % compared with balanced proportion of larger, moderate and smaller aggregates. Neither the seedbed condition nor seeding depth caused significant variation in seedling height or seedling dry weight. 相似文献
1000.
The contamination of forages and grain feeds with ochratoxigenic moulds and ochratoxin A was examined. The investigations were carried out over a period of three years in all seasons. Feeds were found to be contaminated with moulds at a high level throughout the three research years. The highest percentage (95 to 100) of contaminated feed samples was noticed during the second year. Total viable counts of moulds established in 1 g of feed samples ranged from 0.5 to 7.8 x 10(6). Penicillium spp. were dominant in mycopopulations isolated from feeds. Ochratoxin-A producing moulds were present permanently. In the summer period of the second research year as much as 94% of the feed samples were contaminated by ochratoxigenic Penicillium species. P. verrucosum var. cyclopium P. verrucosum var. verrucosum, P. commune and P. chrysogenum, i.e. ochratoxin-producing moulds, were the most prevalent Penicillium species throughout the three-year investigation. Ochratoxin A was found in various feeds in all seasons, except in summer of the first research year. Concentrations of the toxin varied from traces to 400 micrograms/kg. It occurred consistently in the same types of feeds (hay, dried alfalfa, fresh alfalfa, concentrate, pelleted sugar beet pulp, corn silage). 相似文献