Follicular development of sows at weaning in relation to estimated breeding value for within-litter variation in piglet birth weight.
Animal
; 13(3): 554-563, 2019 Mar.
Article
em En
| MEDLINE
| ID: mdl-29983130
ABSTRACT
In this study we aimed to identify possible causes of within-litter variation in piglet birth weight (birth weight variation) by studying follicular development of sows at weaning in relation to their estimated breeding value (EBV) for birth weight variation. In total, 29 multiparous sows (parity 3 to 5) were selected on their EBV for birth weight variation (SD in grams; High-EBV 15.8±1.6, N=14 and Low-EBV -24.7±1.5, N=15). The two groups of sows had similar litter sizes (15.7 v. 16.9). Within 24 h after parturition, piglets were cross-fostered to ensure 13 suckling piglets per sow. Sows weaned 12.8±1.0 and 12.7±1.0 piglets, respectively, at days 26.1±0.2 of lactation. Blood and ovaries were collected within 2 h after weaning. The right ovary was immediately frozen to assess average follicle size and percentage healthy follicles of the 15 largest follicles. The left ovary was used to assess the percentage morphologically healthy cumulus-oocyte complexes (COCs) of the 15 largest follicles. To assess the metabolic state of the sows, body condition and the circulating metabolic markers insulin, IGF1, non-esterified fatty acid, creatinine, leptin, urea and fibroblast growth factor 21 were analysed at weaning. No significant differences were found in any of the measured follicular or metabolic parameters between High-EBV and Low-EBV. A higher weight loss during lactation was related to a lower percentage healthy COCs (ß= -0.65, P=0.02). Serum creatinine, a marker for protein breakdown, was negatively related to average follicle size (ß= -0.60, P=0.05). Backfat loss during lactation was related to a higher backfat thickness at parturition and to a higher average follicle size (ß=0.36, P<0.001) at weaning. In conclusion, we hypothesise that modern hybrid sows with more backfat at the start of lactation are able to mobilise more energy from backfat during lactation and could thereby spare protein reserves to support follicular development.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Desmame
/
Peso ao Nascer
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Cruzamento
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Sus scrofa
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Folículo Ovariano
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Animal
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Holanda