Effects of abomasal protein and energy supply on wool growth in Merino sheep

1992 ◽  
Vol 43 (6) ◽  
pp. 1353 ◽  
Author(s):  
PJ Reis ◽  
DA Tunks ◽  
SG Munro
Keyword(s):  
Amino Acids ◽  
Energy Supply ◽  
Essential Amino Acids ◽  
Merino Sheep ◽  
Lattice Design ◽  
Wool Growth ◽  
Extra Energy ◽  
Whole Milk ◽  
Wool Proteins ◽  
Protein Supply

The relative importance for wool growth of energy-yielding nutrients compared with amino acids required for incorporation into wool proteins was assessed in an experiment in which most nutrients were supplied via the abomasum. Nine nutritional treatments, providing three levels of protein (53, 99 and 145 g/day) to the intestines at three levels of energy (5.2, 7.5 and 9.7 MJ/day), were given to 12 Merino sheep during three consecutive periods of 3 weeks in a balanced lattice design. Abomasal nutrients consisted of varying proportions of casein, whole milk, glucose and glycerol. There was a large effect of protein supply on all components of wool growth, but there was no significant effect of energy. There was a significant interaction between the effects of protein and energy supply on diameter, length growth rate and volume of wool, but it was small relative to the main effect of protein. Extra energy appeared to enhance wool growth at the highest level of protein but reduce it at the lowest level of protein. The concentration of urea, cystine, methionine and other essential amino acids in plasma increased with protein level. Increasing energy supply reduced the concentration of urea and essential amino acids in plasma but not that of cystine or methionine. The experiment confirmed the major role of amino acid supply in controlling wool growth but indicated that there may be a small interaction with energy supply.

Effects of the infusion of amino acids into the abomasum of sheep, with emphasis on the relative value of methionine, cysteine and homocysteine for wool growth

1990 ◽  
Vol 114 (1) ◽  
pp. 59-68 ◽  
Author(s):  
P. J. Reis ◽  
D. A. Tunks ◽  
S. G. Munro
Keyword(s):  
Amino Acids ◽  
Folic Acid ◽  
Adverse Effects ◽  
Essential Amino Acids ◽  
Vitamin B ◽  
Merino Sheep ◽  
Wool Growth ◽  
Relative Value ◽  
Nonessential Amino Acids ◽  
Maintenance Ration

SUMMARYMerino sheep were given abomasal infusions of various amino acids or mixtures of amino acids. Effects on wool growth were measured using autoradiography or a clipping procedure and changes in the concentration of amino acids in plasma were measured in some experiments.Mixtures of five (28 g/day) or ten (45 g/day) essential amino acids (both mixtures containing 3 g methionine) stimulated wool growth of sheep receiving a maintenance ration; on average, the volume of wool grown increased 48% and 86%, respectively. When cysteine completely replaced methionine in these mixtures, wool growth was markedly reduced, but two-thirds of the methionine could be replaced by cysteine without affecting wool growth. Homocysteine was partially effective in replacing methionine and, when supplemented with betaine, folic acid and vitamin B12, the mixture was still significantly inferior to that containing methionine. In contrast, abomasal supplements of methionine or homocysteine alone were equivalent as supplements for wool growth. The results indicated a specific role for methionine in the control of wool growth, other than the provision of cysteine. This role was postulated to be related to some function of S-adenosylmethionine.Infusion often essential amino acids caused appreciable increases in the concentrations of cystine, methionine, cystathionine and taurine in plasma; total essential amino acids increased threefold whereas nonessential amino acids decreased in concentration. The replacement of methionine in the infusion by cysteine or homocysteine significantly altered the concentration of cystine, methionine and cystathionine in plasma.Evidence was obtained that the adverse effects on wool growth of high abomasal doses of methionine (10g/day) could not be reduced or prevented by provision of additional glycine and were not related to the supposed toxic effects of 3-methylthiopropionic acid, a metabolite of the transamination pathway.

scholarly journals Effects of Growth Hormone Administration on Wool Growth in Merino Sheep

1988 ◽  
Vol 41 (2) ◽  
pp. 177 ◽  
Author(s):  
PC Wynn ◽  
ALC Wallace ◽  
AC Kirby ◽  
EF Annison
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Energy Intake ◽  
Nitrogen Balance ◽  
Daily Administration ◽  
Maintenance Energy ◽  
Merino Sheep ◽  
Growth Hormone Administration ◽  
Hormone Administration ◽  
Wool Growth

The effects of daily administration of 10 mg of highly purified ovine growth hormone (GH) for a period of 4 weeks on wool growth have been measured in 12 Merino ewes fed either a calculated maintenance energy intake or 1�6 times this amount (six on each ration). Concentrations of hormones, glucose, urea, a-amino N and amino acids in the blood were monitored and faeces and urine collected for measurement of nitrogen balance.

Utilization of amino acids by pre-ruminant lambs. III.* The influence of age and the dietary proportions of essential and non-essential amino acids on the levels of urea, ammonia and free amino acids in the blood plasma of milk-fed lambs

1978 ◽  
Vol 29 (1) ◽  
pp. 145 ◽  
Author(s):  
H Dove
Keyword(s):  
Amino Acids ◽  
Plasma Levels ◽  
Free Amino Acids ◽  
Free Amino ◽  
Essential Amino Acids ◽  
High Plasma ◽  
Whole Milk ◽  
Wide Range ◽  
Pattern Characteristic ◽  
Pre Treatment

Jugular blood samples were obtained from 10.5 kg and 28 kg lambs receiving a diet of reconstituted cows' whole milk. The lambs were then given diets in which the proportion of essential amino acids (BAA) in the dietary crude protein was altered over a wide range. A second blood sample was taken after lambs had received such diets for 12 days. Plasma obtained from these samples was analysed for free amino acids, urea and ammonia. The pattern of plasma free amino acids (PFAA) in lambs given reconstituted cows' whole milk is described. In both the pre-treatment and post-treatment samples, the heavier lambs appeared to have lower plasma levels of all EAA, and high plasma levels of glycine, serine, urea and ammonia. In the lighter lambs, there were pronounced responses of PFAA levels to changes in the dietary proportion of EAA. At low proportions, the levels of most EAA in plasma were low. Lysine and phenylalanine were exceptions. In addition, levels of many non-essential amino acids (non-EAA), particularly serine and glycine, were high. At high proportions of EAA, plasma levels of all EAA, especially methionine, rose markedly. Within the non-EAA, serine, proline and glycine were reduced, while taurine and cystathionine increased. In the plasma of the heavier lambs, the response of some amino acids to a given dietary change differed from the response in the lighter lambs. This was especially true of methionine, tyrosine, phenylalanine and arginine. There was also marked between-animal variation in plasma levels. When expressed as molar proportions of total PFAA, results were similar to those of the lighter lambs. There was a pronounced similarity between the response of the PFAA to diets with a low proportion of EAA, and the PFAA pattern characteristic of developing kwashiorkor. __________________ *Part II, Aust. J. Agric. Res., 28, 933 (1977).

Nutrition of the bacon pig. XIX. The requirement of the bacon pig for certain essential amino acids

1958 ◽  
Vol 50 (2) ◽  
pp. 230-242 ◽  
Author(s):  
R. E. Evans
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Energy Supply ◽  
Essential Amino Acids ◽  
Food Utilization ◽  
Biological Value ◽  
Potential Value ◽  
The Past

The addition of essential amino acids to all-vegetable diets, so as to raise the biological value of their proteins to the level of animal-protein concentrates, has often been advocated in the past by animal nutritionists. This aim was frustrated in practice since it was impossible, until recently, to secure the necessary supplies at prices that would make such additions economical. Feeding stuffs with added amino acids are now being sold commercially. This is possible following the manufacture of synthetic DL-methionine and crude L-lysine monochloride.It seemed desirable, therefore, to carry out investigations into the potential value of these amino acids to the pig feeder. This paper deals with the effect on growth, food utilization and retention of nitrogen of adding small amounts of lysine and methionine to the diet. An attempt is made to correlate the amino acid composition of the pig's diet with its rate of growth, the energy supply being adequate.

INFLUENCE OF PROBIOTIC FEED ADDITIVE «ENTERO-ACTIVE» ON AMINO ACID COMPOSITION OF BROILER CHICKEN MEAT

2020 ◽  
pp. 270-278
Author(s):  
Y. Poberezhets
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Broiler Chickens ◽  
Broiler Chicken ◽  
Amino Acid Content ◽  
Essential Amino Acids ◽  
Feed Additive ◽  
Average Dose ◽  
Isoleucine Leucine ◽  
Protein Supply

The research has proved that the usage of probiotyk in feeding of broiler chicken facilitate increasing of the digestibility of amino acids including irreplaceable. Revealed that the digestibility of amino acids was highest in broilers consumption average dose supplements investigated. It should be noted that the increased digestibility of the essential probiotic amino acids, such as: lysine, histidine, arginine, valine, methionine, isoleucine, leucine. Thus, the use of probiotic supplements improve the usefulness of protein supply. Such positive changes result in the increasing of broiler efficiency. The research has proved that the usage of different doses of probiotic supplements «Entero-active» has positively effects on amino acid content in meat of broiler chickens. Specifically, the thoracic and femoral muscles of poultry raised the level of most essential amino acids. Thus, consumption of probiotic feed broilers improves meat quality.

Effects on wool growth of the infusion of mixtures of amino acids into the abomasum of sheep

1978 ◽  
Vol 90 (1) ◽  
pp. 173-183 ◽  
Author(s):  
P. J. Reis ◽  
D. A. Tunks
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Volume Growth ◽  
Fibre Diameter ◽  
Essential Amino Acids ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Standard Mixture ◽  
Wool Growth

SUMMARYMerino sheep were given abomasal infusions of either mixtures of amino acids or protein during periods of 8 or 12 days. Effects on wool growth were measured using autoradiography and a clipping procedure which allowed time for the emergence of the wool fibres. Estimates of volume growth rate, from the autoradiographic measurements, and of mass of wool grown, from clipping, were in good agreement.An infusion of a standard mixture of 13 amino acids, which included ten essential amino acids in approximately the proportions in casein, consistently stimulated wool growth. The mean increases in volume and mass of wool grown, during 30 infusions, were 66 and 67% respectively. A mixture of ten essential amino acids alone appeared to be as effective as the standard mixture for stimulating wool growth, and there were no significant differences between the effects on wool growth of casein and the standard mixture of amino acids.The omission of methionine from an infusion of the standard mixture of amino acids, or from a mixture of essential amino acids only, inhibited wool growth rate; both fibre diameter and length of wool grown per day were reduced to below the control values. In addition, the strength of the fibres was considerably reduced.Infusions of zein and of an amino acid mixture simulating the essential amino acid composition of zein both inhibited wool growth rate, due to a reduction in fibre diameter. Similar effects on wool growth were observed when any one of three essential amino acids (lysine, isoleucine or leucine) was omitted from an infusion of the standard mixture of amino acids. The omission of five other essential amino acids (arginine, histidine, phenylalanine, threonine or valine) from the infusion, or variations in the proportions of leucine, lysine or methionine, had no appreciable effects on wool growth.

scholarly journals The amino acid requirements of the preruminant calf

1979 ◽  
Vol 41 (2) ◽  
pp. 311-319 ◽  
Author(s):  
A. P. Williams ◽  
D. Hewitt
Keyword(s):  
Amino Acids ◽  
Wheat Gluten ◽  
Nitrogen Retention ◽  
Live Weight ◽  
Essential Amino Acids ◽  
Apparent Digestibility ◽  
Plasma Urea ◽  
Whole Milk ◽  
Amino Acid Requirements ◽  
The Mean

1. Ten calves (50–58 kg live weight) were given a diet consisting of diluted whole milk, wheat gluten and supplemented with appropriate nutrients including amino acids but deficient in lysine. The lysine requirements of these calves, which were growing at approximately 0.25 kg/d, were estimated from responses to lysine supplementation of this diet. From plasma urea, plasma lysine, nitrogen retention and apparent digestibility of N responses the estimated lysine requirements were 8.5, 7.5, 7.2 and 7.6 g/d respectively.2. From the mean lysine requirement (7.8 g/d) and the ratio, lysine: other essential amino acids in carcasses of similar calves the estimated requirements were (g/d): methionine 2.1, cystine 1.6, threonine 4.9, valine 4.8, isoleucine 3.4, leucine 8.4, tyrosine 3.0, phenylalanine 4.4, histidine 3.0, arginine 8.5, tryptophan 1.0.

The influence of abomasal supplements of zein and some amino acids on wool growth rate and plasma amino acids

1976 ◽  
Vol 86 (3) ◽  
pp. 475-482 ◽  
Author(s):  
P. J. Reis ◽  
D. A. Tunks
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Volume Growth ◽  
Fibre Diameter ◽  
Essential Amino Acids ◽  
Fibre Volume ◽  
Plasma Amino Acids ◽  
Leucine Supplementation ◽  
Length Growth ◽  
Wool Growth

SummaryMerino sheep were given abomasal infusions of (i) zein (80 g/day), (ii) zein (80 g/day) supplemented with L-lysine (6 g/day), L-tryptophan (1 g/day) or lysine and tryptophan together, or (iii) L-leucine (20 g/day). Effects on wool growth (length growth rate, fibre diameter, fibre volume growth rate and mass of wool grown) and on plasma amino acids were measured.Zein increased length growth rate and decreased fibre diameter; on average the volume growth rate and mass of wool grown were not significantly altered. The addition of tryptophan to the infusion of zein did not significantly alter wool growth, whereas the addition of lysine significantly increased all aspects of wool growth. The responses to these treatments were rapid and were adequately assessed during 12-day infusion periods. The infusion of leucine did not cause any appreciable changes in wool growth.Leucine supplementation increased the concentration of leucine in blood plasma about six-fold. Zein decreased the concentration of lysine and ornithine in plasma and increased the concentration of several essential amino acids; leucine was increased about seven-fold. The addition of tryptophan to zein had no effects on plasma amino acids, whereas lysine decreased the concentration of several amino acids in plasma and markedly increased lysine.

scholarly journals Variation in the Sulphur Content of Wool of Merino Sheep Associated with Genetic Differences in Wool-Producing Capacity

1966 ◽  
Vol 19 (6) ◽  
pp. 1179 ◽  
Author(s):  
LR Piper ◽  
CHS Dolling
Keyword(s):  
Amino Acids ◽  
Seasonal Variation ◽  
Nutritional Status ◽  
Inverse Relationship ◽  
Copper Deficiency ◽  
Sulphur Content ◽  
Merino Sheep ◽  
Wool Growth ◽  
Number Of Factors ◽  
The Relationship

The sulphur content of wool may be influenced by a number of factors. Copper deficiency has been shown to reduce sulphur content (Marston 1946), while the administration of sulphur-containing amino acids or casein directly into the abomasum has been shown to increase substantially both the sulphur content of wool and the rate of wool growth (Reis and Schinckel1961, 1963, 1964). Variation in the nutritional status of both pen-fed (Reis 1965) and grazing (Reis and Williams 1965) sheep, associated with variation in either the amount or the composition of the diet, has also been shown to influence sulphur content; wool growth and sulphur content have both increased as nutrition has been improved, and vice versa. Variation in the sulphur content of wool from grazing sheep has also been reported by Ross (1961, 1964) who suggested that there was an inverse relationship between rate of wool growth and its sulphur content. The sheep observed by Ross were Romney ewes and Reis and Williams (1965) have cast some doubt on the relationship suggested by Ross on the grounds that the seasonal variation in wool growth may have been affected by factors other than nutrition.

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