Založba Univerze v Ljubljani / University of Ljubljana Press
Doi
Abstract
Measurement of adaptability and stability of a breed in different environmental conditions might be assumed as good indicator for ecological, ethological and ethical norms in animal production. Indeed, a good adaptability and stability in reproduction performances, in a given environment, can be assumed as a proof that animals are in good well-being condition. The aim of this study was to assess adaptability and stability indexes for fertility traits of four local chicken breeds (the Ermellinata di Rovigo: PER, the Pèpoi: PPP, the Robusta Lionata: PRL and the Robusta Maculata: PRM) reared in three different environments (mountain, hill and plain areas) of the Veneto region. Data consisted on 338 hatchings recorded from February 2002 to May 2004. The percentages of fertile eggs per hatching (pFE), non-hatched eggs per hatching (pNH) and percentage of chicks born alive (pBA) were used as dependent variables. An ANOVA for each reproduction trait was performed to estimate genotype by environment (GxE) interaction. A high GxE interaction was detected for all reproduction traits in particular for pBA. The PER was the best breed in terms of adaptability and stability. On the contrary, the breed that showed to be poorly adapted to all environments and scarce stability over time was PPP. The PRL and PRM seem to be more similar to PPP than PER. In conclusion, more study on GxE interaction should be done to obtain more information on adaptability and stability of animal breeds in different environmental and time period conditions. Animal welfare and relationship between animal and environment should be known and subsequently used for defining better norms and rules for a modern animal production activities.Meritve prilagodljivosti in stabilnosti pasem v različnih okoljskih pogojih bi lahko bile dober pokazatelj ekoloških, etoloških in etičnih norm živalske prireje. Dobra prilagodljivost in stabilnost reprodukcijskih sposobnosti v danem okolju bi lahko bila dokaz, da se živali dobro počutijo. Cilj predstavljene raziskave je bil oceniti indeks prilagodljivosti in stabilnosti za reprodukcijske lastnosti lokalnih pasem kokoši (Ermellinata di Rovigo: PER, Pèpoi: PPP, Robusta Lionata: PRL in Robusta Maculata: PRM). Živali so redili v treh različnih okoljih (gorsko, hribovito in ravninsko) v regiji Veneto. Podatki, vključeni v raziskavo, so pridobljeni od 338 valjenj zabeleženih od februarja 2002 do maja 2004. Kot odvisne spremenljivke so bili v izračunu uporabljeni naslednji parametri: odstotek oplojenih jajc na valjenje (pFE), neizvaljenih jajce na valjenje (pNH) in odstotek izvaljenih piščancev (pBA). Za določitev interakcije med genotipom in okoljem (GxE) je bil za vsako reprodukcijsko lastnost opravljen izračun ANOVA. Za vse reprodukcijske lastnosti, posebej pa za lastnost pBA, je bila izračunana visoka interakcija med genotipom in okoljem. Pasma PER je bila najbolj prilagodljiva in stabilna. Nasprotno je pasma PPP pokazala najslabšo prilagodljivost v vseh okoljih in vseskozi skupno najslabšo stabilnost. Pasmi PRL in PRM sta bolj podobni PPP kot PER. Za pridobitev več informacij o prilagodljivosti in stabilnosti različnih pasem v različnih okoljih in časovnih obdobjih bi bilo potrebno opraviti še več raziskav na področju interakcij med genotipom in okoljem. Potrebno bi bilo poznati dobro počutje živali ter odnose med živalmi in okoljem ter jih v prihodnosti upoštevati pri določanju norm in pravil v moderni prireji živali
