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The objective of the study was to demonstrate the course of the vit. C synthesis process in broilers from their 1st to 56th days after hatching as compared to their organ growth and body mass. The vit. C level was established according to Roe-Kuether’s method in the liver, spleen, kidneys and heart of 56 broilers slaughtered in groups of six birds every week. It was proved that in the chicken broilers in their embryonal stage, the greatest amount of vit. C was synthesized by kidneys - 160.6 mg/kg of tissue, then liver - 143.0 mg/kg, slighty less by the spleen - 107.3 mg/kg and heart - 99.0 mg/kg of tissue. Over the first two months vit. C synthesis in the liver increases together with age (from 143.0 to 291.5 mg/kg tissue). The liver weight growth in the first period is similar and proportional to body weight growth, therefore it can be assumed that the liver is a substantial source of vit. C over the first two months after hatching. In the spleen, the vit. C synthesis expressed in mg/kg of tissue was the highest on the first day of life after which it decreased (from 107.3 mg/kg to 56.1 mg/kg) However, an intensive organ weight growth, as much as 56.4 times, caused a considerable increase of the vitamin synthesis by the whole organ (from 0.0108 to 0.316 mg/whole organ). In the first 56 days of the life the heart synthesizes an almost identical amount of vit. C (about 99.0 to 110.0 mg/kg), in terms of mg/kg of tissue. The body weight growth was higher than that of the heart weight (30.5 times and 61.8 times). It should be stated that the heart in this period of time provides a decreasing amount of vit. C. An intensive vit. C synthesis appears in the kidney - from 160.6 mg/kg to 215.6 mg/kg. As kidney weight growth was nearly the same as body weight, it should be confirmed that the kidneys are a major source of vit. C for a young body. Vit. C. synthesis in broilers throughout their first two months increases together with age, yet in some unfavourable environment conditions it may be insufficient. That is way it would be advisable to administer vit. C as a preventive over this period of time.
The aim of the study was to show whether water soluble vitamins contained in fodder may influence the absorption of exogenous amino acids from entrails. Tests were done on live broiler chickens (aged 2-4 months) in which the small intestine was looped. The physiological liquid included amino acids such as: L-threonine, L-valine, L-methionine, L-lysine, L-histidine, L-phenylalanine, L-leucine, L-isoleucine as well as amino acids with water soluble vitamins: thiamin, riboflavin, pyridoxine, nicotine acid, panthotenic acid, cholin, biotin, vitamin C and folic acid. The method of liquid chromatography before and 30 min after the flow through the loop was used to mark the concentration of amino acids in the perfusion liquid. The results of the study indicate a stimulatory effect of the vitamins on the absorption of amino acids in chickens. The influence on absorbing amino acids was highest when the water soluble vitamins were combined together in doses of 10 mg/l, 50 mg/l, 100 mg/l. A significant influence on the absorption of exogenous amino acids for threonine, valine, histidine and isoleucine observed after applying thiamin, riboflavin, cholin and biotin used in separated liquid. Changes in the absorption level of exogenous amino acids in relation to water soluble vitamins may have a stimulating influence on the development and growth in chickens.
The studies were carried out on 35 000 broiler chickens kept in two broiler-houses of Bios type and 11 000 replacement chicks (in two hen houses, 5 500 in each one). Two coccidiostatics were administered, i. e. Cygro (5 ppm) and Diclazuril (1 ppm) as feed additives in broiler chickens. Replacement chickens were being given the coccidiostatics for 16 weeks of their life. In one poultryhouse Diclazuril and in another one Lerbek were used. The efficacy of the coccidiostatics was assessed on the basis of the following factors: an average body weight (broilers — 4 and 8 weeks, replacement chickens — 8 and 16 weeks), feed consumption, mortality, anatomo-pathological examination after Johnson and Reid and parasitological examination. No differences between the broiler chickens treated with Diclazuril and chickens treated with Cygro were found. In the replacement chickens better findings were observed in the group treated with Diclazuril (lower feed consumption, mortality and oocysts output) in comparison to the Lerbek group of chicks. The results of the studies showed that Diclazuril had not side effects, prevented poultry from coccidiosis and did not suppress the development of natural immunity of poultry against the disease.
Campylobacter spp, gramnegative microorganisms, are currently recognized as a major cause of human acute bacterial enteritis. This bacterium frequently promotes a commensal lifestyle in the gastrointestinal tracts of many animals including birds. The main route of human infections is through improperly handled or undercooked poultry meat. This review article intends to present up-to-date research regarding knowledge of how the bacterium establishes commensalism. To date only a few genes that apparently contribute to avian-gut colonization have been identified by standard genetic techniques such as isogenic mutant construction by gene replacement methodology. The post-genomic era has resulted in new instruments for analyzing virulence and commensalism-related mechanisms. The review outlines some currently conducted Campylobacter transcriptome and proteome analyses aimed at the explanation of the adaptation of the bacterium to different environments. The last part of the review concentrates on mechanisms which regulate the chicken gut colonization process, mainly the new, recently described, two-component signal transduction systems.
In chickens (84 birds) divided into 5 groups there was applied stress in the form of binding of legs and wings for 5 hours per day. Blood was taken by bleeding a group of 12 chickens after 1, 3, 7, 14, and 28 days. The level of adrenalin, noradrenalin and corticosterone were determined in the blood. The studies revealed a permanent significant decrease of the tested hormones up to 14 days of the experiment. At day 28 an increase of their levels was noted again. It was found a marked deviations in immunological indices as well.
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