Effect of breed of performance tested boars on ejaculate traits

Abstract

The main objective of the study was to determine the influence of breed on the traits of boar ejaculate: ejaculate volume (VOL, ml), sperm concentration (CON, x106 sperm/ml), total sperm count in ejaculate (TNS, x109 spermatozoa), sperm motility in native ejaculate (MON, %), sperm motility after dilution (MOD, %) and number of doses produced (NPD). The aim was also to evaluate the correlation of the boar performance test traits: average life daily gain (g), backfat thickness measured in two locations (mm), depth of longissimus dorsi muscle (mm) and carcass meat content (%) with ejaculate traits. Total of 931 ejaculates of 36 boars during reproductive exploitation were analysed (16 Landrace boars and 20 Large White boars). The effect was assessed using the procedure of the general linear model of the statistical package SAS 9.1.3 (SAS Inst. Inc., 2002-2003). The model for analysis included the influence of breed, season and the linear regression influence of body weight at the end of the performance test. The correlation of the traits was determined by applying the Pearson's correlation coefficient. Most of the examined ejaculate traits (VOL, CON, MOD and NPD) varied under the influence of boar breed (p lt 0.01; p lt 0.001). Weight at the end of the test (p lt 0.05; p lt 0.01; p lt 0.001) affected all examined traits, except CON and TNS. A weak association was found between production performance and ejaculate traits.

Osnovni cilj istraživanja bio je da se utvrdi uticaj rase na osobine ejakulata nerasta: volumen ejakulata (VOL, ml), koncentracija sperme (CON, x106 spermatozoida/ml), ukupan broj spermatozoida u ejakulatu (TNS, x109 spermatozoida) pokretljivost spermatozoida u nativnom ejakulatu (MON, %), pokretljivost spermatozoida nakon razreĊenja (MOD, %) i broj proizvedenih doza (NPD). Cilj je bio i da se oceni povezanost osobina iz performans testa nerasta: proseĉan životni dnevni prirast (g), debljina slanine merena na dva mesta (mm), dubina dugog leĊnog mišića (mm) i sadržaj mesa u trupu (%) sa osobinama ejakulata. Analiziran je 931 ejakulat od 36 nerasta tokom reproduktivne eksploatacije (16 nerasta landrasa i 20 nerasta velikog jorkšira). Procena uticaja izvršena je primenom procedure opšteg linearnog modela statistiĉkog paketa SAS 9.1.3 (SAS Inst. Inc., 2002-2003). Model za analizu obuhvatao je uticaj rase, sezone i linearni regresijski uticaj telesne mase na kraju performans testa. Povezanost osobina utvrĊena je primenom Pirsonovog koeficijenta korelacije. Većina ispitivanih osobina ejakulata (VOL, CON, MOD i NPD) varirala je pod uticajem rase nerasta (p lt 0,01; p lt 0,001). Masa na kraju testa (p lt 0,05; p lt 0,01; p lt 0,001) uticala je na sve ispitivane osobine, osim na CON i TNS. IzmeĊu proizvodnih performansi i osobina ejakulata utvrĊena je slaba povezanost.