Characterization of progesterone profile, physiological responses, milk composition and blood biochemical and hematological indices at the early stage of lactation in goats

Abstract

ABSTRACTThe aim of this research was to describe the progesterone profile, physiological response, milk composition, and blood chemistry at the early stage (DIM 30-90 days) of lactation (E1:30-50; E2:50-70; E3:70-90 days) in Baladi goats under Egyptian conditions. The serum progesterone level was significantly reduced with the progress of the early lactation period to reach the least concentration (0.24 ng/ml) at the E3 stage of lactation (P=0.001). The daily milk yield was significantly increased with the progress of the lactation to reach the peak at the E2 stage of lactation (P=0.015). The percentage of milk fat was significantly decreased with the progress of the early lactation period (P=0.032). However, the percentages of total solids and SNF were significantly increased in E2 and E3 stages when compared with the E1 stage (P=0.001 and 0.018, respectively). The serum glucose and total antioxidant capacity were considerably reduced with the progress of the lactation period (P=0.047 and 0.039, respectively). In conclusion, Baladi goats showed a decreased serum progesterone level with the progress of the early lactation period and produce milk with a relatively stable protein and lactose contents. Furthermore, Baladi does able to maintain the stability of most blood biochemical parameters during such period.