RESEARCH ON BREASTFEEDING ABILITY OF MERINOS DE PALAS SHEEP - PERIENI ECOTYPE

C. Pascal, L. Stancescu

Abstract
    The Research works carried out had as main objective the ability lactogene and the influence the development of suckling lambs assets are breast-feeding. The biological material studied belongs to the breed Merinos of Palas - ecotype of Perieni reared in the Research and Development Center for Soil Erosion Control, Perieni - Barlad. Working methods used were those specific to this kind of determinations, and the results were statistically processed and centralized procedure using REML (restricted maximum likelihood - plausibility of the restricted maximum) which guarantee the achievement of expected in the normal parameters. In order to evaluate the real lactogen capacity specific to the examined population, the nucleus of sheep reproduction was grouped depending on their livestock generation. Regarding birth weight lambs, the research carried out show the fact that the sheep on the sixth season of calving (generation 2001) produce the heavier lambs (4.915 ± 0.110 kg), and the most easily accessed by primipare. Weight difference between these two lots were separately significant for p> 1%.
    As in the first part of the evolution of life increase the growth of lambs is based almost exclusively on consumption and breast milk intake, the mean specific growth of the total and daily average was determined by two distinct periods: birth - 20 days respectively for the 28 days and 85 days.
    In the first period examined (0-28 days) growth average absolute growth of lambs was 5.954 ± 0.181 kg, the average values over the population is made of sheep lambs produced at the first, fifth and sixth calving. This shows that after calving, the dynamic weight is more related to the production of individual milk than milk production feature race.
    In the second analysed interval (28 - 85 days) statistical average absolute increase of growth recorded for the whole population is at 11.116 kg. Compared to this value, lambs produced from ewes mothers who belonged to generations in 2009, achieved a total average growth increase of 10.77% lower. Average daily growth analysis performed for the same period of time for each lot and for the total population, confirming the very good rate of growth, which has the ecotype Perieni of the breed Merinos of Palas.
    Based on surveys and estimates made, it was found that the average milk yield achieved at the population of sheep taken in study is in the first 85 days of 74.234 l. The good level of average milk production confirms a very good lactogen capacity specific to the Perieni sheep ecotype, and as a result of this, lambs have enough milk to grow during the period of lactation. On the basis of obtaining good yields of milk, the sheep belonging to all generations analyzed, is the state of maintenance and the optimal diet, provided a constant throughout the year.
    In the first part, the coefficient of correlation between the amount of milk consumed and the rate of growth of lambs values are higher, r_p: 0.84 for the 0-15 days and r_p respectively: 0.79 for the 16-28 days. During the second lactation, the connection between the quantity of milk and the growth increase of lambs drops to r_p: 0.46 for the 43-55 days and r_p: 0.24 for the lactation period between 71 and 85 days.

Key words: Merinos of Palas, nursing capacity, lambs, milk sheep