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The effect of β-glucan, carotenoids, oligosaccharides and anthocyanins on bacteria groups of excreta in broiler chickens
15-20Views:670This study was conducted to examine the effect of natural compounds, such as β-glucan, carotenoids, oligosaccharides, and anthocyanins in the diet on bacteria gropus of excreta in Ross 308 broiler chickens. Chickens were fed 5 diets: control (basal) diet, a diet supplemented by β-glucan at 0.05%, and diets supplemented by carotenoids, oligosaccharides, or anthocyanins at 0.5% of each compound. On experimental day 19, excreta were collected to determine the proportion of Lactobacillus, Bifidobacterium, Campylobacter, Clostridium, and Escherichia coli. Samples were collected aseptically and snap-frozen in liquid nitrogen. Bacterial DNA was isolated from samples, then polymerase chain reaction using primer pairs designed to the 16S rDNA of bacterial groups were applied to define the proportion of the mentioned bacteria. Another universal primer pair was used to amplify a region of 16S rDNA of all the examined bacteria. Proportion of each bacterial groups was determined relatively to the intensity of universal PCR product band by gel documenting system and ImageLab software. Based on the results, carotenoids and anthocyanins increased the proportion of Bifidobacterium, which might imply the beneficial effects of the mentioned compounds on the bacteria composition of excreta.
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Milestones in the development of agronomic management practices in crop production
203-209Views:245From the dawn of the history of the human race, agriculture has always been a profound activity of mankind producing food and feed as well as various plant originated materials for further processing.
Agronomy, like any other human activity, depends on the perpetual development of knowledge and technical skills, - in a modern context – science and innovation. This paper is intended to provide the reader with information regarding the main phases of the development of agricultural production from the Neolithic societies through the early Mesopotamian and Egyptian empires to the inventions of first organised learned society of Rome. The major research findings of the past two millennia including agro-chemistry, genetics and technical development are presented.
Such a review should not lead to any scientific conclusions, but rather a philosophical postulate similar to that of Jonathan Swift written some centuries ago: “And he gave it for his opinion, that whoever could make two ears of corn, or two blades of grass, to grow upon a spot of ground, where only one grew before, would deserve better of mankind, and do more essential service to his country, than the whole race of politicians put together”.
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Simulation Experiments for Observation of Different Genetic Parameters
46-49Views:177The change of genetics variance in various simulated population were examined trough 25 generations. The population size were 1000, 2000, 4000, 8000 and 16000. The number of genes were1, 2, 3, 4 and 5. Two allels per gene were applied. It was assumed that base population was randomly mated. Also it was assumed that a pair of allel genes was independent, there was no epistasis, linkage between alleles of different loci, dominance and overlapping generations. In the selection was kept the 93% of females and 0.186% of males. The size of populations was close to constant through generations.
The size of populations and the number of loci were effects that how many generation is necessary to get genetical maximum. The change of the genetical mean of the population and the genetical variance were well subscribed cube and logistical curve. We can use to estimate these genetical parameters with the previous functons. -
Survival analysis of sow longevity and lifetime reproductive performance – Review
75-80Views:545Sow longevity plays an important role in economically efficient piglet production. Improving sow longevity results increase in the productivity and profitability of a sow herd. Longevity is a complex trait with many factors that can contribute to a sow having a long and productive life. Not only the sow’s genetics, but also nutrition, environment and the management policies are important. In addition, the removal of non-productive sows along with the introduction of replacement gilts is an essential part of maintaining herd productivity at a constantly high level. The objective of this paper was to summarize the current knowledge about the sow longevity and lifetime performance values, as well as, discusses the survival analysis methods for sow longevity traits. This method can estimate the hazard rate indicating proportional risk of sows being culled at any given time, in addition, it is able to investigate the effects of different factors on longevity. Identifying factors that influence the longevity could assist many commercial pig producers in becoming more efficient.
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The olive (Olea europaea) and the almond (Prunus amygdalus) related phytonutrients, and the associated health-promoting biological effects, a review
11-24Views:378With the increasing attention to the health promoting activities of the bioactive compounds from some plants, many researchers are focusing on the biological potential and mechanisms of certain cultivated plant species. In this review, we survey the olive and almond based extracts specific phytoconstituents and their associated health promoting effects that have been evaluated in experimental and clinical studies.
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Some Practical and Biotechnological Methods for Improving Reproduction Traits in Sheep
15-20Views:232However, reproduction in sheep is seasonal, many breeds of sheep are able to mate not only in autumn, but out-of-season as well. The main factor determining seasonality is the photoperiod, but other factors can influence reproductive pattern, such as genetics, management practices and social cues. The fertility of spring and early summer breeding is usually lower; this imposes the need for alternative methods (e.g. hormonal treatments, biotechnological practice), to increase the conception rate.
The author summarize the main practical techniques and biotechnological methods for controlling reproduction completed with some own experimental results in connection with different topics.