The influence of different amounts of linseed (0, 2, 4, 6, 10 and 15%) in rations of 660 Cobb-broilers on fattening parameters, some-blood parameters of metabolism, the content of IMF, the pattern of fatty acids and the stability of fat was investigated in two fattening experiments.In spite of the same rations and environment the fattening parameters were different in this two experiments.In the first experiment 10% of linseed in ration resulted in decreased growth parameters. The feedintake and the weight of broilers in the second experiment were reduced with 2% of linseed in feed already. After feeding the ration with 6% of linseed the weight of animals decreased by 153 g compared with the controll group.Containing 10 and 15% of linseed the weight decreased by 277 and 442 g per animal, respectively. The content of IMF and the total cholesterol and trigylcerides in blood were not influenced by feeding linseed. The pattern of fatty acids in edible parts (meat), in abdominal fat and in IMF changed significantly. The contents of oleic and linolic acid decreased insignificantly, the content of the linolenic acid increased by more than one order.The results of the Rancimat-test demonstrated decreased stability of fat against oxygen by increased amounts of Linseed. Consequently the taste of meat changed after storage.It can be recommended a maximum supplementation of 2% of linseed for starter and fattening rations for broiler.

Three experiments were carried out to investigate the effect of 0-5000 IE vitamin A/kg semisynthetic diet in 2100 hy brids of chicks. The experiments lasted 20, 6 and 4 weeks, respectively.The vitamin A supply did not influence the rearing performance during the first two weeks after hatching. At the third week of life food intake and life weight gain were reduced in laying hens without vitamin A supplementation. Their feed efficiency was impaired. As a rule there were no significant differences between the groups with 750-5000 IE vitamin A supply regarding the obtained parameters. Furthermore, the vitamin A concentration in feed correlated with the vitamin A content of the liver and plasma, but there was a negative correlation with the vitamin E content of the liver. Further parameters like various enzymes, triglycerides, hormon of the thyroidea, the immune response to human's gammaglobuline and RBC's of sheep in blood plasma and the blood picture were also obtained.750 IE vitamin A/kg diet are essential to avoid clinical deficiency symptomes in chicken and young laying hens. They request 1500 IE and 500 IE vitamin A/kg diet, respectively for an optimal life weight gain. 3000 IE vitamin A/kg diet are good for a sufficient vitamin A storage in the liver and an immune response to RBC's of sheep. It os recommened, that including a safty amount the mixed diet of chicken and young laying hens should contain 4000 IE and 2000 IE vitamin A/kg diet, respectively.

In five experiments with 12282 laying hens from 21st to 72st week of age the vitamin A supplement varied between 0-10000 IU per kg mixed feed. Feed intake, egg production, egg weight and feed efficiency per 100 g egg weight are lower without vitamin A supplementation. Between the groups with different vitamin-A-dosages there have been no differences in these parameters. The vitamin A content of liver and egg yolk was positively correlated with the supplementation in the feed (p < 0,05). The body composition of the carcass, the haemoglobine and haematocrit value of the Mood as well as the antibody response against human-gamma-globuline and lipopolysaccharids of S. dublin were not influenced by the vitamin-A-supply. It can be concluded that 2500 IU vitamin A per kg feed are required for optimal egg production, that 4000 IU vitamin A are required for optimal egg production including a body reserve and the supplementation of 6000 IU in per kg mixed feed are recommended considering a salety disk.

In an experiment with 405 Hisex white hens rations with 5-20% low glucosinolate rapeseed (RS) or rapeseed meal (RSM) of 00 quality were used. Feed intake, egg production, individual egg weight and live weight gain were reduced in hens fed 5-20% RS and 10-20% RSM. There was a positive correlation between the RS proportion in the ration and the thyroid weight as well as the iodine content of the thyroid. The relation between the iodine content related to one gram of thyroid and the RS proportion was not significant. There were not any significant differences between the RSM groups and the iodine content of the thyroid. The T3 and T4 concentrations in the blood plasma was independent of the RS- or RSM-proportion in the diet. The outward egg quality was not influenced by feeding. The Haugh units were lower when RS or RSM were offered. The fatty acid pattern of the yolk was changed by RS or RSM feeding, particularly the proportion of oleic acid increased. We concluded from the results, RS cannot be recommended for feeding white hens and only a maximum of 5% RSM should be administered.

Zur Prüfung der Einsatzwürdigkeit von Roggen in der Küken‐ und Junghennenfütterung wurde in 3 Aufzuchtversuchen mit 20790 eingestallten Küken Weizen und Gerste durch Roggen substituiert. Dabei kamen Roggenanteile von 0%, 5%, 10% und 20% in der gesamten Aufzucht und Roggenanteile von 10%, 20% und 30% ab der 9. Lebenswoche zum Einsatz. Die Verfütterung roggenhaltiger Rationen beeinflußte die Aufzuchtleistung in der Tendenz negativ. In der Kükenperiode waren der Futterverzehr und die Zunahme in einigen Gruppen signifikant vermindert sowie der Futteraufwand erhöht. Zwischen Körpermasse bzw. dem Futteraufwand und dem Roggenanteil im Junghennenfutter bestand in der Tendenz eine negative Beziehung. Bei Roggenfütterung waren Schnabel‐ und Kloakenverklebungen und feuchte, schmierige Exkremente nachweisbar. Der Einsatz von Roggen in Kükenrationen ist aufgrund vorliegender Ergebnisse nicht zu empfehlen. Im Junghennenfutter sollten nicht mehr als 5 % Roggen eingesetzt werden.

In three trials with a total of 3240 white laying hybrids, 10 to 72% Triticale of the variety "Grado" was used as a substitute for maize and wheat. The feeding of Triticale had no influence on feed consumption, laying performance, feed efficiency, mortality or weight gain. In two of three trials the egg weight was lowered with an increasing amount of Triticale in the diet. After supplementation of 1 or 1.5% sunflower oil to the diets with 50 resp. 72% Triticale the egg weight increased again to the level of the control group. With the exception of one group, there was no correlation between breaking strength and deformation of the eggs. The colour intensity of the egg yolk was decreased with increasing amounts of Triticale in the diet. It can be concluded, that laying hen feed supplemented with oil may contain up to 50% Triticale, but in non-supplemented diets the highest amount of Triticale should be only 20% because of the risk of linoleic acid shortage.

Four experiments with 270, 44, 432 and 66800 Leghorn hens were carried out to investigate the influence of various Mn additions to diets differed in mineral or Ca contents on egg shell quality. The addition of 300 mg Mn/kg diet improved significantly egg shell breaking strength by 4 N over one year. The supply of 50-500 mg Mn/kg diet for 10-24 weeks of the second half of laying year did not influence the egg shell quality. Addition of mineral mixture or Ca grit to layer rations with adequate or higher Mn levels did not influence egg shell strength. High mineral content in a low manganese diet increased number of cracks by 3%. Strength, weight and ash content of tibia were significantly reduced by feeding a low mineral level. Addition of 50-150 mg Mn per kg low mineral diet normalized partially tibia stability in young hens. It was concluded that supplied dietary Manganese influences calcification positively only in young hens. High levels of Ca did not influence the effects of Mn. 50 mg Mn per kg layers mixture have been considered as an essential supply.

In three one-year trials with a total of 8064 laying hybrids diets with different amounts of beta-carotene (0-5 mg) and vitamin A (0-15000 IU) were tested. The laying performance was reduced in rations without supplementation of beta-carotene and vitamin A. The supplementation of 2 mg beta-carotene per kg feed improved the performance to the level of the control group (6000 IU/per kg feed). There was a positive correlation between the beta-carotene-supply in the diet and the vitamin-A-content of egg yolk and liver. With increasing beta-carotene-supplementation the relative recovery of vitamin A was smaller on molecular basis. Under consideration of vitamin-A-content in the egg yolk and liver we calculated an average conversion of beta-carotene into vitamin A of 2:1 on weight basis, but less beta-carotene is converted into vitamin A with increasing beta-carotene-supplementation.