EFFECT OF USING CHUFA TUBERS (CYPRUS ESCULENTUS L.) IN ZARAIBI GOATS DIETS ON THE RESULTANT MILK AND LABENH

ABSTRACT
The purpose of the present study was to investigate the possibility of using Chufa tubers at different levels in Zaraibi goat rations and its effects on the resultant milk and labenh as well as feed utilization and economical return. Twenty four Zaraibi goats during lactation period were divided randomly into four equal groups (6 doses each). Animals in groups G1, G2, G3 and G4 received 0, 5, 10 and 15 g Chufa tubers/ head/ day, respectively in their diets. Results showed that daily feed intake tended to increase (90.95, 91.63, 92.18 and 93.69 g/kg0.75 ) with increasing the levels of Chufa tubers (0, 5, 10 and 15g/h). However, the incorporation of Chufa tubers into goats' diet decreased the daily water consumption, as the highest rate of this consumption was recorded with goats fed the control ration (G1), while the lowest consumption was found with those fed on the ration containing the high level of Chufa tubers (G4). Daily milk yield of Zaraibi goats during most of lactation weeks was significantly (p<0.05) higher as a result of supplementing diet with Chufa tubers. The highest milk yield was recorded with G4 (1.059kg) followed by G3 (1.020 kg) then G2 (0.989 kg) and lastly G1 (0.892 kg) and the differences were significant. Moreover, the effect of treatment on milk fat, total solids and ash contents were significant. But, no noticeable effect for tested rations were observed on other milk contents (protein, lactose and solids non fat). Other milk qualities including flavor, acidity and pH values did not show significant differences with the use of all examined diets. Milk produced by goats fed different diets was used for the preparation of the concentrated yoghurt Mediterranean dairy product "labneh". Supplementation with Chufa tubers, at different levels, did not significantly affected the yield, moisture content, titratable acidity, fat content, salt content, total nitrogen, and soluble nitrogen of labneh after processing or during storage. Higher non-protein nitrogen content was observed in labneh of G1 (control) and G2 (5% chufa tubers). Total volatile fatty acids were increased with increasing supplementation rate of Chufa tubers from 5% (G2) to 15% (G4). The highest score in the assessment of organoleptic characteristics of Labneh was for G3 (10% Gufa) , followed by G4 (15% Chufa tubers), then G2 (5% Chufa tubers). The feed utilization efficiency (kg feed intake/kg milk production) based on DM or CP was better with increasing Chufa tubers levels (0, 5, 10 and 15 g/h/day) in goat rations as improvement in G4 reached approximately 12.6 and 14.8%, more than G1 (control), respectively. Accordingly, the economic efficiency (%) was higher due to using Chufa tubers at levels 5, 10 and 15 g/head/ day compared with the control one.