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RESEARCH ARTICLE

An attempt of using public ambient temperature data in swine genetic evaluation for litter-size traits at birth in Japan

Hitomi Hara A # , Shinichiro Ogawa https://orcid.org/0000-0002-0537-3311 A D # * , Chika Ohnishi B E , Kazuo Ishii C D , Yoshinobu Uemoto A and Masahiro Satoh A
+ Author Affiliations
- Author Affiliations

A Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi 980-8572, Japan.

B National Livestock Breeding Center, Miyazaki Station, Kobayashi, Miyazaki 886-0004, Japan.

C Division of Animal Breeding and Reproduction, Institute of Livestock and Grassland Science, NARO, Tsukuba, Ibaraki 305-0901, Japan.

D Present address: Division of Meat Animal and Poultry Research, Institute of Livestock and Grassland Science, NARO, Tsukuba, Ibaraki 305-0901, Japan.

E Present address: National Livestock Breeding Center, Okazaki Station, Okazaki, Aichi 444-3161, Japan.

* Correspondence to: ogawas897@affrc.go.jp
# These authors contributed equally to this paper

Handling Editor: John Gaughan

Animal Production Science 62(15) 1488-1500 https://doi.org/10.1071/AN21463
Submitted: 6 September 2021  Accepted: 12 April 2022   Published: 31 May 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context: Large-scale genetic evaluation is promising for efficiently improving sow lifetime productivity, and therefore, a reasonable operational model should be pursued to analyse phenotypic data collected from around Japan, where unique seasonality exists. However, the information on establishing the model is currently insufficient.

Aims: To obtain the fundamental information on using ambient temperature information in developing the model for routine swine genetic evaluation in Japan, by analysing total number born, number born alive, and number stillborn collected at a Japanese farm, together with off-farm ambient temperature measured at the nearest Automated Meteorological Data Acquisition System station.

Methods: Five repeatability animal models were exploited, considering the effects of farrowing season (Model 1), farrowing month (Model 2), quadratic regressions of daily maximum ambient temperature of farrowing day (Model 3), season and temperature (Model 4), or month and temperature (Model 5).

Key results: Patterns of the effects of daily maximum temperature of farrowing day estimated using Model 3 were similar to those of farrowing season by Model 1 and those of farrowing month by Model 2. Adding the effect of daily maximum temperature of farrowing day (Models 4 and 5) could explain phenotypic variability better than only considering either of farrowing season or month (Models 1 and 2). Estimated heritability was stable among the models and the rank correlation of predicted breeding values among models was >0.98 for all traits.

Conclusions: The results indicated the possibility that using public ambient temperature can capture a large part of the phenotypic variability in litter-size traits at birth caused by seasonality in Japan.

Implications: This study could support the availability of public meteorological data in the development of flexible operational models for future swine genetic evaluation in Japan.

Keywords: genetic parameter estimation, heat, meteorological observation data, number born alive, number stillborn, on- and off-farm ambient temperature, pig breeding, season.


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