The importance of updated criteria in breeding soundness examination of commercial Nellore bulls for the herd reproductive improvement

ABSTRACT The aim of this work was to compare results breeding soundness examination (BSE) Nellore bulls (n=1257) according evaluation criteria from two different classification tables (traditional-Table1 used since 1997 and an updated-Table2-proposed in 2020). Data were separated into 3 categories: questionable animals Table1 Table2 (Q1Q2), approved (A1Q2) (A1A2). BSE parameters submitted ANOVA (P<005), age groups. Higher (P<0.0001) scrotal perimeter (PE) observed A1A2 category (18-24m=33.4±2.4cm; 24-36m=34.5±2.2cm; 36-48m=36.6±1.7cm; >48m=38.6±1.7cm) compared A1Q2 (18-24m=29.05±0.98cm; 24-36m=30.3±0.6cm; 36-48m=32.9±1.0cm; >48m=34.8±1.0cm) Q1Q2 (24-36m=26.8±2.0cm; 36-48m=30.0±0.1cm; >48m=31.3±1.1cm), for all At the 36-48months (Q1Q2=2.7±0.3; A1Q2=3.2±0.3; A1A2=3.3±0.6) >48months (Q1Q2=3.0±0.4; A1Q2=3.3±0.5; A1A2=3.4±0.5), with better andrological classifications presented higher (P<0.05) body condition score (BCS). Additionally, at >48m, sperm Motility (P=0.0250) Vigor (P=0.0335) (Mot=55.5±14.7%; V=3.21±0.82) (Mot=55.8±12.2%; V=3.23±0.81) (Mot=50.2±17.4%; V=2.77±0.82). It concluded that using strict selection demonstrated PE BCS, regardless age. utilization updated is highly recommended further reproductive potential development field.