Tumor necrosis factor-α, interleukin-6, serum amyloid A, haptoglobin, and cortisol concentrations in sows following intramammary inoculation of Escherichia coli

Abstract

Concentrations of TNF-alpha and IL-6 are promising markers for the identification of periparturient sows with subclinical coliform mastitis. Identification of such sows should help improve the health and survival of piglets.

Morphometric analysis of proinflammatory cytokines in mammary glands of sows suggests an association between clinical mastitis and local production of IL-1beta, IL-6 and TNF-alpha

“…These findings are consistent with previous studies in rats, humans as well as in cows where some baseline constitutive production of cytokines takes place in normal mammary glands [7,23,56]. Similarly, proinflammatory cytokines have also been found in serum/plasma collected from healthy pregnant sows [59] as well as pregnant women [4,24,57]. The proinflammatory cytokines have been proposed to play a physiological role at parturition by being involved in the regulation of the parturition as such [13,29].…”

“…Previously we have shown that the concentrations of IL-6 and TNF-α in blood were higher in sows that developed clinical signs of mastitis compared with sows that remained clinically healthy 24 h after intramammary inoculation with E. coli [59], whereas no differences were found in IL-6 and TNF-α mRNA expression in infected mammary glands between the two groups [60]. The observations here, including the same set of sows, are in accordance with the mRNA data, i.e.…”

“…During the development of mastitis, in the cow as well as in the sow, it has been shown that the proinflammatory cytokines not only provide defence against bacterial infections, but also contribute to the clinical symptoms of disease [5,30,44,46,49,50,59]. For instance, it has been established that IL-1β, IL-6, IL-8, and TNF-α play a role in the initiation of the inflammatory responses following intramammary inoculation with Escherichia coli [6,45,48,59].…”

“…For instance, it has been established that IL-1β, IL-6, IL-8, and TNF-α play a role in the initiation of the inflammatory responses following intramammary inoculation with Escherichia coli [6,45,48,59]. Analyses of biopsies collected from mammary glands of sows inoculated with E. coli demonstrated the transcription of the genes for a number of proinflammatory cytokines, but analyses of IL-6 and TNF-α in the same set of sows revealed that variations in serum/plasma concentrations were not reflected in the mRNA expression in mammary tissues [59,60]. This observation stresses the importance of relating observations at the mRNA level to the functional protein in order to understand the biological significance of the results and to disclose mechanisms of regulation.…”

Apical electrolyte concentration modulates barrier function and tight junction protein localization in bovine mammary epithelium

“…During mammary infection, cytokines interleukin-1 (IL-1␤), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-␣) are elevated in the milk within 6 -8 h following bacterial inoculation of the gland (1,25,27,44). It has been speculated, from work in other tissues, that these chemicals signal changes in milk composition by directly or indirectly affecting the epithelium (4,13,14,19,30).…”