Animal Board Invited Review: Meta-analysis of genetic parameters for resilience and efficiency traits in goats and sheep

Genetic parameters for resistance to gastrointestinal nematodes in sheep: a meta-analysis

“…This recent study, however, only assessed estimates from 37 articles for FEC and 11 for FAMACHA©, and their literature search only returned 505 heritability estimates for 35 traits including FEC and FAMACHA, compared to the search in the present study, which returned 591 estimates for parasite resistance traits alone. Another study provided a meta-analysis of “resilience traits” in sheep and goats using data derived from 13 EU partners and published articles (Mucha et al, 2022). These included heritability estimates of 0.29±0.03SE for FEC, 0.18±0.07 for “parasite antibody” and 0.36±0.06 for “parasite immunoglobulin”, based on 116, 6 and 24 estimates respectively, although the literature search process was not transparent and the difference between parasite “antibody” and “immunoglobulin” traits was unclear.…”

“…To address this question, it is essential to determine whether the heritability of resistance to GIN is dependent on the trait that is measured. and estimates for FEC, parasite antibodies and parasite immunoglobulins of 0.29, 0.18 and 0.36 (Mucha et al, 2022). Furthermore, these studies reported a favourable "global" genetic correlation of -0.19 for FEC and body weight (Medrado et al, 2021) and non-significant correlations between FEC, parasite immunity and body weight (Mucha et al, 2022).…”

“…While very common in medical science (Gurevitch et al, 2018; Lean et al, 2009), meta-analysis has rarely been seen in livestock science, although that picture has changed recently (Hayward et al, 2021; Mavrot et al, 2015; Zaatout and Hezil, 2022). Two recent meta-analyses have analysed published genetic parameters for a variety of economically-important traits in sheep, including body weight, growth, wool production, carcass parameters, reproductive parameters, longevity and diseases (Medrado et al, 2021; Mucha et al, 2022). These studies provided “global” heritability estimates for FEC and FAMACHA scores of 0.17 and 0.25 (Medrado et al, 2021) and estimates for FEC, parasite antibodies and parasite immunoglobulins of 0.29, 0.18 and 0.36 (Mucha et al, 2022).…”

“…Two recent meta-analyses have analysed published genetic parameters for a variety of economically-important traits in sheep, including body weight, growth, wool production, carcass parameters, reproductive parameters, longevity and diseases (Medrado et al, 2021; Mucha et al, 2022). These studies provided “global” heritability estimates for FEC and FAMACHA scores of 0.17 and 0.25 (Medrado et al, 2021) and estimates for FEC, parasite antibodies and parasite immunoglobulins of 0.29, 0.18 and 0.36 (Mucha et al, 2022). Furthermore, these studies reported a favourable “global” genetic correlation of −0.19 for FEC and body weight (Medrado et al, 2021) and non-significant correlations between FEC, parasite immunity and body weight (Mucha et al, 2022).…”

“…These studies provided “global” heritability estimates for FEC and FAMACHA scores of 0.17 and 0.25 (Medrado et al, 2021) and estimates for FEC, parasite antibodies and parasite immunoglobulins of 0.29, 0.18 and 0.36 (Mucha et al, 2022). Furthermore, these studies reported a favourable “global” genetic correlation of −0.19 for FEC and body weight (Medrado et al, 2021) and non-significant correlations between FEC, parasite immunity and body weight (Mucha et al, 2022). Both studies reported substantial heterogeneity in genetic parameters, but neither investigated the moderator variables associated with this variation, and the breadth of economic parameters that were investigated did not facilitate an exhaustive search of the literature.…”