Selected serum acute-phase proteins in peripartum sows and evaluation of their diagnostic usefulness.

Lactation impairment in sows is a frequent and significant clinical problem. Due to a complex aetiopathogenesis, early diagnosis of postpartum dysgalactia syndrome (PDS) is difficult and so far has usually been based on physical examination performed in the first days after farrowing. To date no data have been provided on the diagnostic usefulness of acute phase proteins (APP) in early diagnosis of peripartum disorders, including lactation disorders in sows. This study aimed at measuring the serum concentration of selected APP (C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA) and pig major acute phase protein (Pig-MAP)) in sows with physiological and pathological course of the peripartum period and at evaluating the possibility of utilising the studied markers in the early diagnosis of lactation disorders. Also, the correlation between the studied APP serum concentration and production parameters was assessed. To the best of the authors' knowledge, the present study is the first such performed on sows. The experiment was conducted on 139 sows divided into three experimental groups based on the course of peripartum period: HEALTHY (n = 58) - clinically healthy sows, PDS (n = 45) - sows with milk production disorders, and OTHERS (n = 36) - sows which had experienced difficult parturitions, inflammations not connected with mammary glands (abscesses, hooves infections), or lameness. Thirteen serum samples from each sow were analysed, samples being taken on days -28 (-30 to -25), -14 (-16 to -11), -7 (-8 to -6), -5, -3, -1, 0 (parturition day), +1, +3, +5, +7, +14 and +28 (prior to or post farrowing). In order to measure the level of serum APP, commercial, quantitative ELISA tests were used. The results of the study indicate that the diagnosis made on the basis of the assessment of SAA levels on day 7 before the farrowing was not statistically different from the diagnosis made on the basis of the physical examination in the first days after the farrowing, that is the so-called "gold standard". The achieved results indicate that SAA may be a useful early marker of lactation impairments in sows, which allows detection of which sows are susceptible to lactation disorders with high probability even as early as one week before parturition.