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K. El-Shazly

Bio: K. El-Shazly is an academic researcher from Alexandria University. The author has contributed to research in topics: Rumen & Population. The author has an hindex of 12, co-authored 31 publications receiving 450 citations.
Topics: Rumen, Population, Dry matter, Urea, Nitrogen balance

Papers
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Journal ArticleDOI
TL;DR: It was concluded that the rumen ciliate protozoa are essential for the metabolism and growth of young lambs.
Abstract: A survey of the components of the rumen ciliate population in a series of adult sheep, raised in the Faculty of Agriculture, University of Alexandria, has shown that a mixture of Entodinium, Isotricha, Ophryoscolex, Diplodinium, and Polyplastron species was found in the rumen contents of Egyptian sheep; no Epidinium and a negligible number of Dasytricha ruminantium were also observed. The microbial population, reducing sugars, ammonia, volatile fatty acids (VFA) production, and growth rate of 14 lambs inoculated with whole rumen contents from a mature sheep were compared over a 6-month period with those of 13 lambs maintained under the same conditions, except that they were strictly isolated from other ruminants. Certain large oval organisms and large numbers of flagellates and Oscillospira were frequently observed in the rumen contents of the isolated lambs. The reducing sugars, ammonia, and VFA levels, measured before and at intervals after feeding, in the inoculated lambs showed a pronounced rise above the values found in the ciliate-free animals. The propionic acid-acetic acid ratio in the rumen contents of the faunated lambs was considerably higher than in the nonfaunated controls. The inoculated lambs grew faster than the isolated lambs. Differences in weight gain which ranged from 15 to 17% were statistically significant. The inoculated animals impressed the observers by their good appearance which was superior to that of the ciliate-free lambs. It was, therefore, concluded that the rumen ciliate protozoa are essential for the metabolism and growth of young lambs.

103 citations

Journal ArticleDOI
TL;DR: In this paper, the nutritive values of the nitrogenous constituents of some concentrates used in Egypt as supplements in summer rations (decorticated cottonseed cake, linseed-oil meal and beans (Vicia faba)) and of animal proteins (meat meal, fish meal and casein) and of barseem (Trifolium alexandrinum).
Abstract: 1. Ten successive trials with two Rahmany adult ewes were carried out with the aim of comparing the nutritive values of the nitrogenous constituents of some concentrates used in Egypt as supplements in summer rations (decorticated cottonseed cake, linseed-oil meal and beans (Vicia faba)) and of animal proteins (meat meal, fish meal and casein) and of barseem (Trifolium alexandrinum). Wheat straw was employed as the main roughage in the ration. Nitrogen intake for all supplements was 10·16 g./day.2. Apparent digestion coefficients for crude protein were estimated. Casein had the highest digestibility coefficient while meat meal was the least digestible.3. Nitrogen retention and ruminal ammonia curves are given for each period. Only three proteins, namely, barseem, cottonseed cake and linseed meal gave positive nitrogen balance at the critical level of nitrogen intake used throughout the trials. Fish meal improved nitrogen retention significantly. Meat meal and beans did not improve nitrogen retention. The addition of 70 g. starch to beans improved nitrogen retention significantly.

39 citations

Journal ArticleDOI
TL;DR: The inoculated lambs have higher blood haemoglobin, protein N, and lower reducing sugars, ammonia N,, and urea N values than those of the uninoculate lambs.
Abstract: 1. The levels of blood reducing sugars, haemoglobin, protein N, NPN, ammonia N, and urea N in addition to the nitrogen retention and digestibility coefficients of food constituents, were studied in lambs with and without ciliate protozoa. 2. The inoculated lambs have higher blood haemoglobin, protein N, and lower reducing sugars, ammonia N, and urea N values than those of the uninoculated lambs.

33 citations

Journal ArticleDOI
TL;DR: There was a tendency for higher VFA and ammonia-N concentrations in the rumen of inoculated calves and there was no difference between inoculated and uninoculated calves in blood urea and blood reducing sugars.

31 citations

Journal ArticleDOI
TL;DR: In this article, a protein index for animal feeds is suggested as a basis for the criteria relating nutritive value to chemical composition, and regression equations for predicting the nutritive values gave a reasonable level of accuracy (0·18−14·74% error).
Abstract: A protein index for animal feeds is suggested as a basis for the criteria relating nutritive value to chemical composition. The feeds were classified into four main groups: legumes, non-legumes, straws and concentrates. The regression equations for predicting the nutritive value gave a reasonable level of accuracy (0·18–14·74% error). Higher levels of accuracy were attained employing regression equations formulated for more homogenous feed subgroups classified according to their protein and fibre contents. The percentage error resulting from the use of the specific equations was found to range between zero and 9·88.

30 citations


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Book
20 Dec 1991
TL;DR: In addition to the bacteria in the rumen there are many larger organisms which at various times have been designated protozoa, of which there are two groups both in the subclass Trichostomatia and the entodiniomorphs.
Abstract: In addition to the bacteria in the rumen there are many larger (5–250/mm long) organisms which at various times have been designated protozoa Of these the ‘ovals’ (Quin’s and Eadie’s) are now known to be large bacteria (Orpin, 1976) and the ‘flagellates’ Neocallimastix frontalis, Piromonas communis and Sphaeromonas communis are the zoospores of phycomycete fungi (Orpin, 1977a, b) There are genuine flagellates in the rumen, eg Trichomonas spp, Monoceromonas sp and Chilomastix sp, but almost nothing is known about their metabolism (Jensen and Hammon, 1964) The largest, most obvious and most important protozoa are the ciliates, of which there are two groups both in the subclass Trichostomatia The so called ‘holotrich’ protozoa belong to the order Vestibuliferida and the entodiniomorphs to the order Entodiniomorphida, suborder Entodiniomorphina and family Ophryoscolecidae As the properties and metabolism of these two protozoal groups are different, they will be considered separately below

903 citations

Journal ArticleDOI
TL;DR: In this article, chemical constraints that may be responsible for the decrease in fiber digestion are explored, and a major factor appears to be rumen pH, to approximately 6.5 or 5.0, which results in depressed growth rates and decreased fibrolytic organisms.

802 citations

Book ChapterDOI
TL;DR: This chapter discusses the direct effects of increase in the global atmospheric CO 2 concentration on natural and commercial temperate trees and forests and the impact on the ecology and environment of woods and forests, and the downstream, socio-economic consequences.
Abstract: Publisher Summary This chapter discusses the direct effects of increase in the global atmospheric CO 2 concentration on natural and commercial temperate trees and forests. The aim of this chapter is to assess what is known of these relationships in trees, and to predict the consequences of an increase in CO 2 on temperate zone forests. Information concerning the reaction of trees and forests to increase in the atmospheric CO 2 concentration is particularly important. The total amount of carbon stored in terrestrial ecosystems has diminished over recent centuries as a result of anthropogenic actions, especially forestry clearance. On a global scale, this further reduction in area of forest will both exacerbate the rise of CO 2 in the atmosphere through oxidation of wood and wood products, and reduce the sink strength for CO 2 . . Because of the complexity of forest ecosystems, there may be many consequences of long-term changes in the rates of carbon gain and water loss by trees and stands. The four main reasons for being concerned about the rise in CO 2 and its effect on trees and forests given here are: the enhancement of biological knowledge about the functioning of tree species of major ecological and economic importance, the impact on the productivity and value of the economic product, the impact on the ecology and environment of woods and forests, and the downstream, socio-economic consequences.

727 citations

Journal ArticleDOI
TL;DR: Experiments on root and rhizosphere response in plants grown in CO(2)-enriched atmospheres will be reviewed and, where possible, collectively integrated, to offer a series of hypotheses which are considered as priority targets for future research.

726 citations

Journal ArticleDOI
TL;DR: This review summarizes recent advances in 4 major areas of bioHydrogenation: the microorganisms involved, identification of intermediates, the biochemistry of key enzymes, and the development and testing of mathematical models to predict biohydrogenation outcomes.
Abstract: Recent advances in chromatographic identification of CLA isomers, combined with interest in their possible properties in promoting human health (e.g., cancer prevention, decreased atherosclerosis, improved immune response) and animal performance (e.g., body composition, regulation of milk fat synthesis, milk production), has renewed interest in biohydrogenation and its regulation in the rumen. Conventional pathways of biohydrogenation traditionally ignored minor fatty acid intermediates, which led to the persistence of oversimplified pathways over the decades. Recent work is now being directed toward accounting for all possible trans-18:1 and CLA products formed, including the discovery of novel bioactive intermediates. Modern microbial genetics and molecular phylogenetic techniques for identifying and classifying microorganisms by their small-subunit rRNA gene sequences have advanced knowledge of the role and contribution of specific microbial species in the process of biohydrogenation. With new insights into the pathways of biohydrogenation now available, several attempts have been made at modeling the pathway to predict ruminal flows of unsaturated fatty acids and biohydrogenation intermediates across a range of ruminal conditions. After a brief historical account of major past accomplishments documenting biohydrogenation, this review summarizes recent advances in 4 major areas of biohydrogenation: the microorganisms involved, identification of intermediates, the biochemistry of key enzymes, and the development and testing of mathematical models to predict biohydrogenation outcomes.

669 citations