Biomedical subjects

I Halle

Publications and source records attributed to I Halle.

22 records · Page 2Linked to original sources

PubMed1984

[Effect of graded nitrogen supplements on egg protein synthesis and body protein retention in broiler hens].

In the top laying period (29th/30th week of life) egg protein synthesis and protein retention in the bodies of laying hens were ascertained. Based on egg-N analyses, the relation between N-intake/live weight0.67kg and egg-N discharge/kg LW0.67kg was regressively calculated and described. The subtraction of egg-N discharge/LW0.67kg from N-balance/LW0.67kg made it possible to estimate N-retention/LW0.67kg in the body. From the intersection of this curve with the chi-axis it follows that the broiler hen meets the N-requirement for maintenance and egg production with a daily consumption of 1,264.7 mg N/LW0.67kg, which corresponds to 15.8 g crude protein, and then neither loses nor retains body protein. At a daily intake of this amount of CP (15.8 g) the broiler hen produces 44.1 g egg per day. An energy intake of more than 70 EFUhen/animal and day resulted in fat retention in the broiler hen.

Animals↗

PubMed1984

[Protein utilization as well as crude protein and amino acid requirements of broiler hens].

After N-balance experiments with broiler hens in the top laying period and the feeding of soybean coarse meal/fish meal protein the protein utilisation values were calculated. The PNu curve and the PEW curve could be described as utilisation values from the N-retention curve (e-function). At an intake of N at which the hen neither decomposed nor retained protein, the utilisation (PNu) for maintenance and egg production was 55.3% and the utilisation of feed protein for egg production 49.4%. Maximum PEW 34.3% could only be ascertained at an N-intake/LW0.67kg of 1500 mg. The corresponding crude protein quota of 18.7 g recommended as crude protein requirement is calculated from this N-quota (xm) and a live weight of the broiler hen of 2804 g. For the same N-quota (xm) and the same live weight of the hens this results in a necessary quota of S-AA of 694 mg per hen and day. Provided the daily feed intake is 145 g and thus the intake of crude protein 18.7 g and that of S-AA 694 mg per hen, the necessary crude protein content of the feed is 130 g per kg original substance and an S-AA concentration which is equivalent to 3.7% of the crude protein (in g/16 g N).

Amino Acids↗

PubMed1983

[Methodological studies on determination of the digestibility of crude protein in chickens].

A comparison of various methods for the determination of the digestibility of crude protein in chickens was made. The chemical methods of dividing faeces and urine according to HARTFIEL and EKMAN were tried out, and a new method based on the determination of alpha-NH2-N was developed and tested. Colostomy of hens served as the basis of the comparison for the correctness of the chemical methods. The best approximation to the digestibility quotient of the crude protein according to colostomy was achieved with the alpha-NH2-N-method, which can to a large extent be well automated and can do without N-determination. Faeces-urine-N-separation according to EKMAN also resulted in a good approximation to the values according to colostomy.

Animals↗

PubMedDate not supplied

[Evaluation of the energy concentration of feed mixtures for poultry based on the chemical analytical data].

Based on data material available for 33 feed mixtures, several regression equations were developed which make the estimation of energy concentration (EC) on the basis of the content of crude nutrients possible. The values received from the various equations were compared with those resulting from digestibility experiments with colostomized male and female chickens. An estimation equation is recommended resulting from the regressions for the digestibility of the individual crude nutrients: EC = 0.604 X crude protein content + 2.045 X crude fat content + 0.901 X crude carbohydrate content-158.3.

Animal Feed↗