sc. A. Hennig

Untersuchungen zum Jodstoffwechsel

: The influence of J-deficiency on reproduction was tested in model experiments with goats and mini pigs, partly through several reproduction cycles including the descendants after intra-uterine depletion as well. The effect of 0.05 mg J/kg dry matter in the concentrated feed (total ration 0.03)--0.04 mg J/kg dry matter) for goats was a diminished success of first inseminations, a higher frequency of abortions, high mortality and poorer development of the kids. All J-deficiency goats and kids suffered from hypertrophy of the thyroid gland, half of all J-deficiency kids were born hairless. Concerning the mini pigs, 0.06 mg J/kg dry matter even after intra-uterine depletion had no detectable influence either on conception or the mortality and development of the piglets. The thyroid gland of all deficiency pigs was enlarged, however. The hypertrophy of the thyroid gland makes it easy to diagnose J-deficiency visually.

Untersuchungen zur ergotropen Wirksamkeit von 2,3-Dimethylchinoxalin-1,4-dioxid bzw. 2-Methylchinoxalin-1,4-dioxid am wachsenden Broiler bei Verwendung hydrokolloidreicher Rationen sowie von Broilermastalleinfutter

2,3-dimethyl-quinoxaline-1,4-dioxide and 2-methyl-quinoxaline-1,4-dioxide proved to be ergotropic in the feeding of a hydrocolloid ration as well as of a broiler fattening feed. They are at least equal to Nitrovin. The ergotropic effect of the hydrocolloid ration was higher than that of the conventional ration. For this reason methylated quinoxaline-1,4-dioxides are considered as belonging to the intestinal stabilisers. They increased nutrient and energy retention and decreased feed efficiency by approximately equal to 10%. Residues in the liver, the kidneys and the intestines could only be detected after 10 times the ergotropic amount.

Untersuchungen über die Anforderungen von Puten in Bodenhaltung an den Energie- und Rohproteingehalt des Mischfutters

In four experiments with 9,500 turkeys assorted according to sex, three energy levels (500, 550 and 600 EFh (energetic feed units for hens = 14,6 kJ net energy body fat of hens)/kg feed) were combined with three levels of crude protein (250, 300 and 350 g/kg feed) in the mixed feed (9 rations) and tested under conditions of keeping the turkeys on the ground from hatching to their 42nd day of life. The feed consumption of the turkeys did not correlate with the energy content of the mixed feed. The energy consumption of the groups whose mixed feed had a high energy content (550 and 600 EFh) was significantly higher than that of groups whose feed had a low energy content. With the increasing content of crude protein in the mixed feed the consumption of crude protein per turkey and test period rose significantly. Due to the increase of the content of energy and crude protein, the live weight gain increased after a 28- and 42-day test period; the growth-stimulating effect was more distinct with male animals. Mortality had no connections with nutrition. For the starting-off feed for turkeys an energy content of < 580 EFh with 300 g crude protein per kg mixed feed up to the 4th/5th week of life is recommended.