The parturition-relevant hormone profile in hyper-prolific sows under different housing conditions

Abstract

Objective

Aim was to characterize birth-relevant hormone profiles of reproductively productive hybrid sows in the peripartum period. It was examined whether there are deviations in the hormone profile depending on the birth process (eutocia:dystocia) and the type of housing (box stall BS vs. farrowing pen FP vs. group housing GH).

Materials and methods

A total of 40 healthy, heavily pregnant hybrid sows (German Landrace x Large White) with a gestation number≥ 2 were available. The distribution between the housing types was: BS n=18, FP n=15, GH n=7. All births occurred after the biologically completed gestation period. Blood samples were taken via indwelling catheters (113th day ante partum to 4th day post partum). Progesterone (P4), oestradiol (E2), prostaglandin F2α and its metabolites (PGFM), relaxin, oxytocin, cortisol, adrenaline and noradrenaline were determined.

Results

The ratio of eutocia:dystocia was 15:25. Dystocia occurred regardless of type of housing. The only reason for dystocia was a weak labor (>60 min). The litter size was 17.73± 3.85 piglets. Differences in the hormone profiles between eutocia and dystocia were as follows: P4 tended to be higher in dystocia p=0.0776; oxytocin higher in eutocia (not significant), 12.5% of sows permanently with hypoxytocinemia; cortisol p=0.0503; noradrenaline p=0.0098. The type of housing had the following influence on the hormone profile: P4 p=0.046; E2 p=0.0009; PGFM p=0.0108; relaxin p=0.0022; noradrenaline p=0.0078.

Conclusions and clinical relevance

The parturition-relevant hormones are related to the parturition and to the type of housing during birth. The hormone profiles obtained could be of use in the discussion about the animal welfare-oriented housing system in the peripartum phase in pigs. The proportion of sows of the hyperproliferative line studied with permanent hypoxytocinaemia in stage II of parturition is remarkable. The ratio of eutocia:dystocia is unevenly distributed. Dystocia occurred regardless of the type of housing.

Zusammenfassung

Gegenstand und Ziel

Zweck dieser Untersuchungen war es, geburtsrelevante Hormonprofile von reproduktiv leistungsstarken Hybridsauen in der peripartalen Periode zu charakterisieren. Es wurde überprüft, ob Abweichungen im Hormonprofil in Abhängigkeit vom Geburtsverlauf (Eutokie vs. Dystokie) und von der Haltungsform (Kastenstand KST vs. Bewegungsbucht BWB vs. Gruppenhaltung G) bestehen.

Material und Methoden

Die Untersuchung fand unter Feldbedingungen statt. Zur Verfügung standen 40 gesunde, hochgravide Hybridsauen (Deutsche Landrasse x Large White) mit der Gestationsziffer≥2. Die Verteilung auf die Haltungsformen war: KST n=18, BWB n=15, G n=7. Alle Geburten traten nach biologisch beendeter Gestationszeit ein. Die Blutentnahmen erfolgten über Dauerkatheter (113. Tag ante partum bis 4. Tag post partum). Progesteron (P4), Östradiol (E2), Prostaglandin F2α (PGF_2α) und seine Metaboliten (PGFM), Relaxin, Oxytocin, Cortisol, Adrenalin und Noradrenalin wurden untersucht.

Ergebnisse

Das Verhältnis Eutokie:Dystokie betrug 15:25. Dystokien traten unabhängig von der Haltungsfom auf. Einziger Grund für einen dystokischen Verlauf war eine Wehenschwäche (> 60 min). Die Wurfgröße lag bei 17,73±3,85 Ferkeln. Abweichungen im Hormonprofil bestanden zwischen Eutokie und Dystokie wie folgt: P4 tendenziell höher bei Dystokie p=0,0776; Oxytocin höhere Werte bei Eutokie (nicht signifikant), 12,5% der Sauen dauerhaft mit Hypoxytocinämie; Cortisol p=0,0503; Noradrenalin p=0,0098. Die Haltungsform hatte folgenden Einfluss auf das Hormonprofil: P4 p=0,046; E2 p=0,0009; PGFM p=0,0108; Relaxin p=0,0022; Noradrenalin p=0,0078.

Schlussfolgerungen und klinische Relevanz

Die gemessenen, geburtsrelvanten Hormone weisen teilweise Beziehungen zum Geburtsverlauf, teilweise zu den Haltungsbedingungen unter der Geburt auf. Die erstellten Hormonprofile könnten in der Diskussion um die tierwohlgerechte Haltungsform im peripartalen Abschnitt des Reproduktionszyklus beim Schwein von Nutzen sein. Bemerkenswert ist der Anteil an Sauen der untersuchten hyperproliferativen Linie mit einer dauerhaften Hypoxytocinaemie im Stadium II der Geburt. Das Verhältnis Eutokie:Dystokie ist ungleich verteilt. Die Dystokien traten unabhängig von der Haltungsform auf.

Keywords

Birth - dystocia - farrowing crate - farrowing pen - hormone - parturition - prolific sows

Schlüsselwörter

Geburt - Dystokie - Kastenstand - Bewegungsbucht - Hormon - hyperproliferative Sauen

Deceased

Publication History

Received: 13 November 2024

Accepted: 07 January 2025

Article published online:
03 March 2025

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