Einfluss des Energie- und Proteinniveaus sowie der Proteinqualität auf die Milchleistung der Bunten Deutschen Edelziege

Abstract. Title of the paper: Influence of energy level and dietary protein quality and quantity on the lactation performance of German Fawn Goats
In this study two feeding trials were conducted using a total of 45 goats (German Fawn) to estimate milk yield for a lactation period of 150 days. Goats were fed corresponding German (high, H) and International (low, N) feeding standards for milk production. At each feeding level the diet had either protected (P, formaldehyde) or unprotected (U) Soya meal, resulting in different UDP amounts. The diets used in the trials had different protein contents: V1 low (11.9–12.3%) and V2 high (15.9–16.6%) respectively. The diet were composed of hay and pellets with energy contents ranging from 11.3 to 11.6 MJ ME/ kg DM. The milk yield was 40% lower in groups of V1 as compared to groups of V2 which is mainly attributed to the decreased energy and protein intake, partly caused due to low feed intake and the lack of RDP for optimal rumen microbial activity in V1. There also existed a strong correlation between feed intake and protein content of the diet. Feeding of protein protection resulted in an increased protein amount at duodenum and the goats gave a higher milk yield, provided a sufficient RDP level was secured.

A high protein content in diet (16%) at middle and late lactation induced a protein surplus which is combined with inefficient energy utilisation. During the lactation period the diets have to be adapted not only for energy but also for protein needs