TY - JOUR AU - Aguirre-Valverde, Judyana AU - Vargas-Leitón, Bernardo AU - Romero-Zuñiga, Juan José PY - 2013/11/27 Y2 - 2024/03/28 TI - Effects of inbreeding on reproductive parameters of Costa Rican Holstein and Jersey cows. JF - Agronomía Mesoamericana JA - Agron. Mesoam. VL - 24 IS - 2 SE - Articles DO - 10.15517/am.v24i2.12523 UR - https://revistas.ucr.ac.cr/index.php/agromeso/article/view/12523 SP - 245-255 AB - <p>The objective of</p><p>this study was to analyze the effect of high inbreeding (F)</p><p>levels (≥ 6.25%) on reproductive parameters of Holstein and</p><p>Jersey cows born between Jan 1995 and Dec 2010 in specia<span>lized</span></p><p>dairy herds in Costa Rica. Data on age at first calving</p><p>(AFC), open days (DO) and services per conception (SPC)</p><p>from (n=263 804) from the VAMPP national data base, at the</p><p>Veterinary School of the Universidad Nacional, was used.</p><p>An F value ≥ 6.25% (high/risk) was used as a cut-off point.</p><p>The data were processed using descriptive statistics, multiple</p><p>linear regression (mixed model), and logistic regression. A</p><p>17.9% of animals had some inbreeding, with an F average of</p><p>0.42% (0.49% and 0.55% for Holstein and Jersey). 22.6% of</p><p>Holstein and 20.3% of Jersey were inbreed; however, in Jer<span>sey,</span></p><p>there were cows with higher F. Cows with some inbree<span>ding</span></p><p>have an average F of 2.16% for Holstein and 2.98% for</p><p>Jersey. Furthermore, cows with low F had 18 d less of AFC</p><p>(p&lt;0.01) compared to those with high F. Regarding the DO,</p><p>there were +0.53 d for animals with low F (P= 0.71); while</p><p>the cows with low F had +0.08 SPC (P&lt;0.01). There was no</p><p>risk of DO or SPC in animals with F ≥ 6.25%; which occurred</p><p>for AFC (OR = 1.23; 95% CI: 1.10-1.38). According</p><p>to this study, inbreeding did not affect the DO, but slightly</p><p>affects the SPC and the AFC in Holstein and Jersey cows.</p> ER -