The effect of the system of crossing on fattening parameters of weaned lambs

Abstract

In this paper, the effect of different systems of crossing of sheep: two-breed (PxW) and three-breed (PxWxIDF) on production results - body weight and average daily gain of lambs weaned at the age of 60 days and fattened to age of 120 days, was investigated. Also, the effect of crossing on consumption and conversion of food and nutrients was monitored. Study was carried out on the Experimental sheep farm of the Institute for Animal Husbandry, Belgrade-Zemun, and following breeds were used in the crossing: Pirot Pramenka (P), Wurttemberg (W) and Ile de France (IDF). Pirot Pramenka was used as the maternal basis, while Wurttemberg rams were used as sires, and as terminal breed, Ile de France rams were used. Results have shown that the three-breed crosses of F1 generation, compared to two-breed crosses, obtained higher body gain for 19.23% with lower food intake for 5.19%, during fattening period lasting from 60th to 120th day of age. Regarding feed conversion ratio, they used per 1 kg of body gain 29.61% less hay and 20.82% less concentrate feeds. Positive biological effect exhibited in three-breed crosses (PxWxIDF) is consequence of individual heterosis and maternal heterosis.

U radu je ispitivan uticaj različitih sistema ukrštanja ovaca: dvorasnog (PxW) i trorasnog (PxWxIDF), na rezultate u pogledu mase tela i prosečnog dnevnog prirasta jagnjadi zalučene sa 60 dana i tovljene do 120 dana uzrasta. Takođe su praćeni efekti ukrštanja na konzumiranje i konverziju hrane i hranljivih materija. Istraživanja su obavljena na eksperimentalnoj farmi ovaca Instituta za stočarstvo Beograd-Zemun, a za ukrštanje su korišćene sledeće rase ovaca: pirotska pramenka (P), virtemberg (W) i Il de frans (IDF). Rezultati su pokazali da su trorasni melezi u odnosu na dvorasne, u tovu od 60. do 120. dana uzrasta ostvarili za 19.23% veći prirast i za 5.19% manje konzumiranje hrane. U pogledu konverzije hrane, po kg prirasta su utrošili za 29.61% manje sena i za 20.82% manje koncentrata. Pozitivan biološki efekat koji se ispoljio kod meleza (PxWxIDF) je posledica korišćenja heterozisa individue i heterozisa majke.