Biomedical subjects

A Hennig

Publications and source records attributed to A Hennig.

At least 127 records · Page 7Linked to original sources

PubMed1975

[Studies on the protein and amino acid metabolism of laying hens using 15N labeled casein. 15N concentration in the intestinal content and intestinal tissue in relation to the time of the last 15N administration].

Four laying hens with anus praeternaturalis were fed 15N casein for a period of 6 experimental days. Each experimental bird thus received a 15N excess (15N') of 154.44 mg. 11.54 mg of 15N' were found in lysine 3.99 mg in histidine and 9.58 mg in arginine. 2 hens were slaughtered 48 hours after the last 15N dose; another 2 were sacrificed after 144 hrs. In this investigation the N content of the intestinal contents and in the proteins of the small and large intestine were determined. The average N content of the small intestine per hen 2.65% that of the large intestine, 2.60% and, correspondingly, the TCE soluble proportion of N was 21.8% and 20.4%. The percentage of amino acids in the contents of the small intestine was found to change relative to that of the dietary proteins, approximating the protein composition of the intestine. In the first two hens the atom % 15N' was found in the different sections of the intestine and in the intestinal contents varied between 0.14 and 0.28. The data obtained from the two hens slaughtered 144 hours after the last 15N' dose were nearly the same ranging from 0.08 to 0.10 atom % 15n'.

Amino Acids↗

PubMed1975

[Influence of endogenous factors on the ash, calciu, magnesium, potassium, sodium, phosphorus, zinc, iron, copper and manganese contents in the bristles of pigs. 4. Effect of time of cutting and heredity on the inorganic components in the hair of the pigs (bristles of sows and piglets, newly grown hair)].

Samples of sow bristles were examined every 3 months. The results obtained confirmed the monthly gathered experimental data on the ash content and the Ca, Mg, K, and Na content (P less than 0.05-0.001) of Boar Bristles. Similarly, investigations made every 3 months showed a significant seasonal influence on the concentration of these mineral components in the bristles of the pigs (P less than 0.05-0.001). A comparison was made between newly grown hair and original bristles showing the presence of other yet unknown factors that had a controlling influence on the mineral composition of the hair. The inorganic components in the short newly grown hair were not different from those found in analogous long hair.

Animals↗

PubMed1975

[Studies on the protein and amino acid metabolism of laying hens using 15N labeled casein. 4. Fecal excretion of nitrogen and amino acids, digestibility of crude protein and absorption of basic amino acids].

Generally, the faeces of laying hens fed 15N casein rations were found to contain equal proportions of TCE-precipitable and TCE-soluble nitrogen. Considerable variations were observed to occur between the 64 samples investigated (27%-75%) and no explanation was found to account for this fact. The content of basic amino acids in faecal proteins was found to differ considerably from that of the proteins in the intestinal contents. A high lysine content was found after the feeding of wheat. The present trial substantiated this result, provided the casein contained a certain proportion of non-available lysine. The apparent and true digestibility of dietary N was 88% or 91%, that of 15N (2nd and 6th day of experiment) and 92%. During the feeding of labelled casein a higher level of N labelling was found in the TCE-soluble portion of the faeces, whereas on the 8th to 12th day a higher level of labelling was observed in the TCE-precipitable portion of the faeces. The peak of 15N excretion occurred on the 3rd day of experiment. When 15N administration terminated the atom% 15N in the faeces and in urine was found to decrease rapidly approximating the initial level of labelling asymptotically.

Amino Acids↗

PubMed1975

[Studies on reducing the crude protein content of feeds fed to chicks and young hens (laying stock)].

2 rearing trials were carried out on a total of 8550 hybrid chicks (White Leghorn) to investigate in which way food mixtures containing reduced levels of crude protein (supplemented or unsupplemented with amino acids) might influence the growth of chicks and young hens. Decreases from 21.5% to 16.5% in the crude protein content of chicken feed and from 15% to 13% in feeds feed to young hens (greater than 8 weeks of life) did not reduce the live weight of birds at the end of the rearing period to any appreciable extent. No clearly defined differences were found to exist between the different types of feed tested concerning the amount of food and energy consumed per unit of weight gain and the mortality rate among the birds; it was shown, however, that the demand for crude protein per unit of weight gain was clearly reduced in birds reared at the lower crude protein level. For young hens receiving the diet poorer in protein the date when the birds began laying was slightly delayed. Otherwise, no statistically significant differences were found to exist between the young birds fed varying levels of crude protein, concerning the age at 50% laying performance and other parameters that are characteristic of the entire laying period (laying performance, weight of individual eggs, food consumption, mortality, fertilization of hatching eggs, hatchability of eggs). It appears that the feeding of a reduced protein diet to chicks and young hens (laying stock) did not have any detrimental effect on the growth and later laying performance of the birds. Apart from the fact that the demand for protein feeds is considerably reduced during the rearing period the costs of feeding per bird can also be cut down.

Animal Feed↗

PubMed1975

[Studies on the influence of various vitamin-B6 uptake in the hen on the nutrient content of liver, pectoral muscle, total body and egg].

The present study included 2 trials which were performed to investigate in which way graded vitamin B6 supplies or vitamin B6 deficiency would influence the chemical composition of the whole body, the liver, pectoral muscle or the eggs of hens and in which way it might change the pattern of amino acid composition in the proteins of the pectoral muscle. The following results were obtained: No direct changes in the protein and fat content of the birds (total body, liver, pectoral muscle) were noted in trial 1 when graded amounts of vitamin B6 were supplied, whereas in trial 2 signifikant increases in the fat content of the body and decrases in the protein levels were observed when vitamin B6 supplements were added to a vitamin-deficient diet (pair-fed group) or fed to animals receiving increased amounts of food (controls). Variations in dietary vitamin B6 concentrations did not produce statistically significant changes in the protein and fat content of eggs, and in the pattern of amino acid composition of proteins in the pectoral muscle. However, with increasing vitamin B6 uptake, the serine to glycine ratio was narrowed.

Animal Feed↗

PubMed1975

[Studies in male sheep on the feeding value of excreta from young hens and broilers].

5 digestibility trials were carried out, each with 4 male sheep, to investigate the excreta of young hens and broilers produced as litter in hen batteries for rearing and fattening stock. Data on the digestibility of organic matter and energy of broiler excreta were 76.0% and 76.4%; i.e. these values were only slightly lower than those for the basal ration (barley + dried green lucerne: 76.6% and 76.8%). Digestibility coefficients for organic matter and energy content in the excreta of young hens were 69.4% and 70.4%, respectively. The protein digestibility of excreta of broilers and young hens was 82.3% and 84.3%; that is to say, the investigated dropping contained 330 g and 260 g of digestible crude protein per kg of dry matter. Due to the high ash content of the samples the energy content of the analyzed excreta was only 474 EFr and 421 EFr per kg of dry matter.

Animal Feed↗

PubMed1975

[Studies using labeled urea on lactating ruminants. 4. Incorporation of 15N-urea into the basic amino acids of goat milk].

Goats were used in a trial to investigate the rate of 15N incorporation from labelled urea into the basic amino acids of the milk (excess of 15N = 24.9 atom%). As early as 20 minutes after administration of the first dose of 15N urea nitrogen labelling in arginine and lysine was observed. The highest level of 15N labelling was noticed for lysine and arginine 24 hrs after start of the trial. The peak values of labelling for histidine were essentially lower. Reference is made to peculiarities of the ruminal metabolism of histidine.

Amino Acids↗

PubMed1975

[Substitution of protein feed through lysine-supplemented high-protein wheat during the rearing and laying period of hens. 4. Effect of graded lysine doses during the rearing of young hens on the performance characteristics during the laying period].

1530 laying hybrid hens kept under conditions of large-scale production were used to test whether varying lysine levels given to young hens would later on influence the production of the birds during their laying period. Thus, young hens received isonitrogenous and isocaloric diets with varying lysine content (group 1-4: 0.59%, 0.61%, 0.54%, 0.46%) and varying sources of lysine (group 1: wheat/fish meal; group 2--4: wheat/synthetic L-lysine). The ration used for the controls was prepared on the basis of nationally prescribed formulas.

Animal Feed↗

PubMed1975

[Studies on the use of wheat rich in crude protein in the feeding of broilers. 1. Experimental procedure, weight gains, food consumption and food efficiency].

A fattening trial was carried out with 8 groups of broilers each comprising 1225 birds. Within this trial tests were made to replace the protein feeds of newly hatched chicks over a period of up to 56 days of age, by wheat rich in crude protein. If wheat with a high crude protein content is fed supplementation with lysine and methionine will be necessary depending on the kind of protein feed used. No supplementation with amino acids is required if rations of fish meal + extracted soya bean meal are used despite their reduced content of these amino acids. The broilers consumed larger quantities of the wheat + extracted soya bean meal+fish meal ration than of the mixtures containing no fish meal. Food requirements per unit of weight gain were the same for the mixtures containing high-protein wheat and for the standard maize ration. The lowest food consumption per unit of weight gain was computed for the wheat + extracted soya bean meal diet supplemented with amino acids. The same quantities of lysine, thioamino acids and threonine were necessary for broilers receiving the wheat rations as for birds of the standard group. Protein feed may be saved by using high-protein wheat in the fattening of broilers. The rates of weight gain obtained with these rations are the same or even better than those achieved with rations of maize + fish meal+soya bean meal.

Animal Feed↗

PubMed1975

[Influence of the cecum, in geese fed diets containing urea, on N-metabolism and digestibility of nutrients and on urea concentration in excrements and blood].

Balance experiments were performed on six normal young geese and on six geese with a ligated caecum. The ration consisted of 43.25% barley, 30% sugar beet slices, 20% cellulose, 1.4% maize germ oil, 3% mineral mixture, 1% concentrate of vitamins and growth factors, 1.25% urea and 0.1% lysine. Daily nitrogen balance was similar in the two groups (average 1051 mg in the controls and 1090 mg in the experimental birds). Crude protein digestibility was 82.4 +/- 1.1% in the controls and 84.9 +/- 1% in the experimental birds (a significant difference). The bacterial flora of the caecum seemed to have no effect on crude fibre breakdown. Digestibility was quite low, averaging 5.7% in controls and 4.6% in experimental birds. The proportion of urea discharged in excreta was 50% in controls and 55.7% in experimental birds. Blood urea veraged 21.7 mg/100 g in controls and 22.8 mg in experimental birds (insignificant difference).

Animal Feed↗

PubMed1974