H.M.F. Galal, M.A.M. Abdel-Hafez, T.  Deraz, A.A. El-Zawahry and A.M. Hussein

Animal Production Research Institute, Agriculture Research Center, Ministry of Agriculture, Giza, Egypt.

Abstract :

The present study was planned to evaluate the nutritive values of strawberry vine hay and the possibility of inclusion this residues as a source of protein and energy in lactating goats under hot conditions of the year and the effect of this residues on physiological status, blood components, milk yield and components. Twenty eight Damascus healthy lactating does (aged 3 - 4 years and weighed 35- 40 kg were divided into four similar groups according to weight, (7 lactating does in each) to investigate the effect of replacing 0%, 30%, 70% and 100% from berseem hay by strawberry vine hay on dray matter basis(G1, G2, G3 and G4) plus concentrate feed mixture to cover 100% NRC requirements. Four digestibility trials were carried out to evaluate the four rations using. 12 mature bucks (3 in each)for digestibility trials. Ambient air temperature (AT) and relative humidity (RH %) were recorded at the times of carrying out the Maximum and minimum temperatures were recorded. Temperature-humidity index (THI) was estimated. Thermoregulatory parameters were recorded biweekly with blood sample. Milk samples were obtained every week, daily milk yield and milk components were determined. Feed conversion and economical efficiency were calculated. Results showed that the lowest values of feed intake as g/h/d was recorded by G4, while the other groups (G1, G2 and G3) were nearly similar. The G2 had the highest values of Relative intake (% of body weight) and g DMI/Kg W^0.75. Digestion coefficients of experimental rations showed that the OM, CP, EE, CF and NFE digestibility were higher in G2 and G3 than in G1 and G4. The feeding value as TDN were significantly higher in G2 than G1 and G4 and the difference between G1 and G3 was not significant, while DCP value of G2 was insignificantly higher than G1 and significantly higher than G3 and G4. The effects of feeding type on physiological measurements showed that the differences among hair surface temperature in all groups were not significant, while hair deep temperature (HDT), skin temperature and rectal temperature were significantly higher in G4 and G3 than G1 and G2 respectively, while the differences between G1 and G2 or G3 and G4 were not significant. Ear temperature in G1 and G2 were significantly lower than in G3 and G4, while the differences between G1 and G2 or G3 and G4 were not significant. Pulse rate and respiration rate of G2 was significantly lower than other groups, but the differences between G1 and G3 were not significant while the G4 was significantly higher than other groups. GOT (AST) and GPT (ALT)  of G2 blood serum  was significantly lower than other groups. The highest values were recorded in G1 and G4, while the differences between G1 and G3 were not significant. Total protein and albumin was significantly higher in G2 than other groups, while the differences among other groups were not significant. Calcium and phosphorus in G2 blood plasma was significantly higher than in other groups. The highest average daily milk yield and 4% fat Corrected Milk (FCM) showed in G2, while the lowest value recorded in G4. Milk yield of G1 and G3 were nearly similar. The differences of chemical composition of milk among all groups were not significant. The best feed conversion (Kg DMI and Kg TDN / Kg FCM) were recorded with G2, while the bad feed conversion were recorded with G4. The highest economical efficiency was showed in G3 then followed G2, G4 and G1, respectively.

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