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Kultury drozdzowe w zywieniu przezuwaczy

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Opracowano charakterystykę kilkunastu izolatów Phomopsis spp., wyizolowanych z różnych gatunków roślin sadowniczych, przy zastosowaniu metod klasycznych i techniki RAPD. Osiem izolatów P. viticola pochodziło z winorośli uprawianej w różnych regionach Polski, po dwa izolaty z jabłoni, gruszy, wiśni, orzecha włoskiego, borówki, leszczyny i żywotnika, a jeden z kasztanowca. Badane izolaty były słabo zróżnicowane w wyglądzie kolonii i rozmiarach zarodników typu alfa, ale stwierdzono zasadnicze różnice w ich patogeniczności w stosunku do pędów winorośli. Największą liczbę pędów z objawami nekrozy obserwowano po zakażeniu przez P. viticola podczas gdy izolaty pochodzące z innych roślin powodowały objawy chorobowe tylko sporadycznie. Wyniki analizy RAPD potwierdziły zróżnicowanie w obrębie badanych izolatów Phomopsis wykazane na podstawie metod klasycznych, co wskazuje, że obie metody wzajemnie się uzupełniają.
The objective of the study was to determine the influence of the herbal preparation Ruchamax®, added to rations for heifers on the number of ciliates in their rumen, ruminal fermentation, and some biochemical parameters in their blood serum. The experiment was carried out on three rumen-fistulated heifers. The control diet (K), comprising 84% of meadow hay and 16% of concentrate, and two experimental diets, composed of the control ration, supplemented with Ruchamax®, were supplied in doses. The experimental groups were fed a diet with 20 g of Ruchamax® administered once a day for 5 (R5) or 14 days (R14). After 5 or 14 days of administration, samples of rumen fluid and blood were taken. In rumen fluid, the number of protozoa, pH, and the concentrations of VFA and ammonia nitrogen, were determined, whereas total protein, urea, total cholesterol, ASP, ALT, and ALP, were measured in blood serum. Supplementation with Ruchamax® significantly increased the number of total ciliates and the genus Entodinium in group R14 compared with the control animals and group R5. The number of ciliates from the genus Ophryoscolex decreased in the rumen of group R14 compared with R5. The number of protozoa from the family Isotrichidae significantly decreased in group R14 compared with the control heifers. The administration of Ruchamax® for 5 days increased the concentrations of ammonia nitrogen and total VFA, but decreased pH in the rumen. In group R14, the molar proportion of propionate, the sum of isoacids, and valerate increased, but acetate decreased significantly compared to the control heifers. Urea and total cholesterol level in serum blood increased after 14 days of supplementation with Ruchamax®. The activities of AST and ALT significantly decreased in group R5 compared with the control animals.
The objective of the present study was to examine and compare the ability of Diploplastron affine and Entodinium caudatum to digest and ferment chitin. Cultivation studies showed that enrichment of the growth medium with this polysaccharide increased the ciliate count (P < 0.05). After 2 h of incubation of ciliates with chitin, a statistically significant increase in the percentage of individuals containing chitin particles was observed (P < 0.05), followed by a continuous decrease (P < 0.05) in this percentage. Enzymatic studies confirmed the ability of the examined protozoa to digest chitin. The chitinolytic activity of Diploplastron affine was 3.9 and that of Entodinium caudatum was 5.9 μmol N-acetyl glucosamine/mg protein/h. The production rates of volatile fatty acids from fermented chitin were 3.9 and 0.5 pmol/ciliate cell/h for Diploplastron affine and Entodinium caudatum, respectively.
The objective of the present study was to investigate how different levels of natural humic acid in the diet affect the hydrolases activity in the rumen of sheep. The experiment was carried out on three rumen-fistulated adult sheep. The control animals were fed a diet (K) containing 59.7% meadow hay, 28.4% crushed barley, 9.8% soybean oil meal and 2.1% vitamin mineral mixture. The experimental diets were composed of the control ration supplemented with humic acid (HUMAC natur AFM® containing 65% humic acid in dry matter) and supplied at doses of 10 g · d⁻¹ (diet H10) or 20 g · d⁻¹ (diet H20). Samples of rumen digesta were collected just before the morning feeding, as well as 2, 4, and 8 h afterwards. In the present study, the cellulolytic activity in the rumen digesta was higher (P < 0.01) in sheep fed the K diet than it was in animals fed the H20 ration 2 h after feeding. However, the effect of humic acid on the cellulose degradation rate depended on the content of humic acid in the diet. The cellulolytic activity was increased 2 h after feeding in sheep fed the H10 diet as compared with animals fed the H20 ration (P < 0.05). Sampling time had significant influence on the hydrolases activity in the rumen of sheep. In sheep fed the H10 ration, the cellulolytic activity was higher 8 h after feeding than it was before feeding and 4 h after feeding (P < 0.05). In the H10 and H20 groups, the xylnalolytic activity was higher before feeding, but lower than it was in the control group K. The degradation rates of xylan were decreased 2 and 4 h after feeding in sheep fed the H10 and H20 rations and then increased 8 h after feeding (P < 0.05). In sheep fed the H20 diet, the amylolitic activity 8 h after feeding was higher than it was 2 h after feeding (P < 0.05). The effect of humic acid on the hydrolases activity in the rumen of sheep is not uniform and depends on the quantity of humic acid in the diet and on sampling time. Humic acid present in commercial HUMAC natur AFM® product enhances the initial rate of cellulose degradation in the rumen at a dose of 10 g · d⁻¹. Thus, it may suggest that humic acid stimulates the growth of fibrolytic microorganisms in the rumen. On the other hand, the present results suggest that humic acid may reduce the rate of carbohydrate degradation in the rumen, since a higher hydrolases activity was observed before morning feeding and 8 h afterwards.
The knowledge of life requirements of phytopathogenic fungi allows to provide the periods of their mass occurrence on plant plantations and determine the optimal conditions for their isolation and culture on artificial media. Areas of occurrence of P. diachenii on caraway plants indicate the thermophilic nature of the fungus although there is a lack of information about research on this topic. In the present study the growth and development of one-spore cultures of six isolates of P. diachenii at the temperature: 0º C, 4º C, 10º C, 16º C, 22º C, 28º C, 33º C and 38º C on Czapek-Dox medium and also the growth and development of the same isolates in eight agar media at the temperature 25°C were examined. It was shown that the optimum temperature for the growth and sporulation of most isolates of P. diachenii and for the secretion of mature conidia from conidioma ranged 22º C to 28º C. Based on the nature of growth and development of P. diachenii on the examined media, Czapek-Dox and mineral ones as slightly acidic, and possibly malt extract should be recommend for isolation of the fungus from the plant tissue. PDA and CzapekDox media were considered the most suitable for diagnostic purposes due to the formation of characteristic macroscopic and microscopic features on these substrates. These substrates with fragments of carnation leaves should be recommended for the stimulation of fungal sporulation.
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W doświadczeniu badano in vitro rozkład białka pasz rozpuszczalnego w wodzie: albuminy bydlęcej, kazeiny, poekstrakcyjnych śrut - sojowej, rzepakowej i arachidowej oraz nasion bobiku i łubinu. Białko rozpuszczalne w badanych paszach wynosiło: albumina - 93,3; kazeina - 85,5; śruta arachidowa - 46,5; śruta sojowa - 37,3; śruta bobikowa - 36,8; śruta rzepakowa - 32,0; śruta łubinowa - 30,0% białka ogólnego. Stężenie amoniaku w inkubatach dla wszystkich badanych białek wzrastało wraz z wydłużającym się czasem inkubacji, wskazując, że tempo dezaminacji rozpuszczalnego białka pasz inkubowanego z treścią żwacza było powolne i różne dla poszczególnych pasz. Brak istotności różnic dla większości oznaczonych współczynników korelacji pomiędzy ilością białka rozpuszczalnego, a stężeniem amoniaku w inkubatach sugeruje, że stężenie amoniaku nie jest właściwym wskaźnikiem tempa dezaminacji białka rozpuszczalnego w płynie żwaczowym.
Tannins are water-soluble polyphenols with anti-nutritional properties but when supplemented at a low dose to the diets may exhibit positive effect on ruminants. Owing to great group diversity, tannins demonstrate various biological activities. They form complexes with nutrients and so they are enable to affect digestion processes. Thus, the aim of the study was to examine the effect of two types of tannins on sheep pancreatic enzymes activity. In the experiment 6 ewe of the Coloured Merino breed, fitted with catheters to the common pancreatic-biliary duct and simple cannula to the duodenum were used. Sheep were divided into 3 feeding groups for crossover design (n = 2), and fed control diet (CON) and two experimental diets with dried lingonberry leaves (VVI) or oak cortex (QUE) in a dose of 3 g ∙ d–1 , as a source of condensed and hydrolysable tannins, respectively. Non-significant effect of tannins on pancreatic-biliary juice secretion and its protein concentration was observed. In sheep fed diets with QUE addition lipase activity was increased in comparison to animals receiving VVI. An upward trend in amylase and trypsin activity after tannins addition was also found. Enriching sheep diets with additives containing tannins slightly stimulated pancreas exocrine activity. However, the inhibitory effects of tannins on endogenous protein activity, similar to the digestive enzymes inhibitors action, cannot be excluded. So, further studies on precise defining the mechanism of tannins action on enzymes activity and digestion process in ruminants are necessary
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