Primerjava plodnosti koz med ekološko in konvencionalno rejo

Zager, Nejc (author), Cividini, Angela (mentor)

Plodnost koz je ena izmed proizvodnih lastnosti in je še posebej pomembna pri mesnih pasmah koz. Pomembna parametra plodnosti sta velikost gnezda in doba med dvema zaporednima jaritvama (DMJ). Na podlagi vprašalnika namenjenega rejcem burske pasme koz smo pridobili informacije o tehnologiji reje od 23 konvencionalnih (K) rejcev in 5 ekoloških (E) rejcev. S statistično obdelavo podatkov o plodnosti, ki smo jih pridobili iz Centralne Podatkovne Zbirke za drobnico (CPZ) za vse vprašane rejce smo analizirali vpliv načina reje (K vs. E) na lastnosti plodnosti v slovenskih pogojih reje. Ugotovili smo, da je v K rejah število rojenih kozličev (1,74 ± 0,01) večje od števila rojenih kozličev v E rejah (1,49 ± 0,02). DMJ je bila v K rejah krajša (362 ± 3,3 dni) kot v E rejah (402 ± 5,2 dni). Na podlagi odgovorov iz vprašalnika ugotavljamo, da imamo v obeh načinih rej v povprečju starejšo populacijo rejcev, ki redijo majhne trope na kmetijskih površinah z majhnim obsegom na hribovsko višinskem in gorskem območju. Iz odgovorov na vprašanja smo ugotovili, da K rejci živali dokrmljujejo, E rejci pa ne. Prav tako K rejci krmni obrok prilagajajo kategoriji in proizvodni fazi živali, kar je lahko razlog za večja gnezda v primerjavi z E rejci. V K kot tudi v E rejah rejci uporabljajo kontinuiran sistem jaritev, hkrati pa kozliče odstavljajo pozno (60-90 dni ali kasneje), kar je lahko razlog za dolgo DMJ okoli enega leta v obeh načinih reje. Ugotovili smo, da je večina jaritev v zimskem in spomladanskem času, kar kaže na večjo spolno aktivnost burske koze v jeseni. Sklepamo lahko, da se je obdobje spolne aktivnosti burske koze v slovenskih pogojih reje skrajšalo na obdobje jesenskih mesecev.

• Language: Slovenian
• Keywords: drobnica, koze, ekološka reja, konvencionalna reja, plodnost
• Work type: Bachelor thesis/paper
• Organization: BF - Biotechnical Faculty
• Year: 2019
• PID: 20.500.12556/RUL-107610
• COBISS.SI-ID: 4213640
• Publication date in RUL: 07.05.2019

ZAGER, Nejc, 2019, Primerjava plodnosti koz med ekološko in konvencionalno rejo [online]. Bachelor’s thesis. [Accessed 16 March 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=107610

Secondary language

• Language: English
• Title: Comparison of goat fertility between organic and conventional farming

Abstract

The fertility of goats is one of the most important production traits in meet breeds. There are two important fertility traits, which are the litter size and period between parities (DMJ). On the basis of the questionnaire that was used by Boer goat breeders, we gathered information about rearing system from 23 conventional (K) and 5 organic (E) Boer goat breeders. Data from the questionnaire and fertility parameters data from the central database from Slovenian Breeding Program for Small Ruminants (CPZ) were analyzed with the statistical package SAS/STAT. The effect of the rearing system (K vs. E) on the fertility traits was determined. Goats in K have higher number of born kids per litter (1,74 ± 0,01) then goats in the E rearing system (1,49 ± 0,02). Period between parities was shorter in K (362 ± 3,3 days) compared to the E rearing system (402 ± 5,2 days). The questionnaire analyzed results determined that in both rearing systems prevailed an older population of breeders that breed smaller flocks which have small areas and lay in high hilly and mountainous landscape. From the answers of the questionnaire we found out that K breeders add additional feed to the goats diet compared to E breeders that don’t add extra feed. In addition we found out that K breeders adjust the goat diet regarding the category and the production phase of the animal, which could be the reason for the higher litter size in K, compared to E breeders. In both, K and E rearing systems, the year-round breeding system is used. In both systems, kids are weaned late (60-90 days late) which is why the DMJ is so long (around one year in both cases). The majority of the kiddings occurred in winter and spring, which points out that the Boer goats under the conditions prevailing in Slovenia are considered seasonally polyestrous with breeding season in autumn.

• Keywords: small ruminants, goats, conventional breeding, organic breeding, fertility