RESEARCH REGARDING THE QUANTITY AND QUALITY OF MILK OBTAINED FROM PRIMIPAROUS SAANEN GOATS REARED IN INDUSTRIAL SYSTEM
Stela Zamfirescu, Daniela Jitariu, N. Dobrin, Dorina Nadolu, Ana Cismileanu, Il. Voicu
The rearing system, the mating season and the nutrition of primiparous Saanen goats have influence on the quantity and quality of milk. The natural mating of Saanen females at 7-9 months of age, with a normal weight of 35-38 kg, has influence on the quantitative production of milk. Given the administration of a feed ration that ensured 2.29 UFL at mating and 3.29 UFL at birth, the primiparous Saanen goats gained 51.50-56.65 kg 30 days after birth. The milk production generated within 240-270 days was 612.2 kg-778.2 kg, with a daily average production of 2.55-2.88 liters. The type of birth (simple or twins) has no influence on the milk production or its quality. The quality control of the milk obtained from the three lots emphasized that the biochemical parameters analyzed have normal values for fat (3.80 %-3.95%), slightly elevated for proteins (3.69%-3.80%), lactose (4.19%- 4.25%) and casein (2.57% - 2.59), and a constant pH of 6.61-6.77. The fat-protein ratio was 1.02-1.04, lower than the normal values of 1.15-1.20. The non-protein nitrogen – g/100g (NPN/CU) from the milk had values under 0.03 in all the lots. NPN/CU is an indicator for the ruminal proteins digestion. The urea nitrogen-MUN (g/100g) displayed very high values, of 16±3.06 in lot 1, and 15.86 in lot 2 and 3. MUN is an indicator that provides information about the status of the energy and protein balance in goats, which is used to monitor feeding and to evaluate the excess nitrogen in the ration. The casein (g/100g) determined in the Saanen goat milk had the following values 2.59 (lot 1), 2.54 (lot 2) and 2.57 (lot 3). In our research, of the total proteins, casein represented 179.9% in lot 1, 75% in lot 2 and 67.6 % in lot 3, being inversely proportional to the daily and total milk production of the lots.
Key words: Saanen goats, primiparous, milk quality