title: Sexually dimorphic innate immunological responses of pre-pubertal Brahman cattle following an intravenous lipopolysaccharide challenge.
abstract: This study was designed to characterize potential sexually dimorphic immunological responses following a lipopolysaccharide (LPS) challenge in beef cattle. Six female (heifers) and five male (bulls) Brahman calves (average age=253 ± 19.9 and 288 ± 47.9 days; average body weight=194 ± 11 kg and 247 ± 19 kg for heifers and bulls, respectively) were challenged with LPS (0.25 μg LPS/kg body weight). Following administration of LPS, all cattle displayed increased sickness behavior beginning at 0.5h, with heifers on average displaying less sickness behavior than bulls. A febrile response was observed in all animals following LPS administration, with a maximum response observed from 4 to 5.5h. The average rectal temperature response was greater in heifers than bulls. In all cattle there were elevated serum concentrations of cortisol from 0.5 to 8h, TNF-α from 1 to 2.5h, IL-6 from 2 to 8h, and IFN-γ from 2.5 to 7h after LPS challenge. Additionally, serum concentrations of TNF-α were greater in heifers than bulls from 1.5 to 2h after the LPS challenge. Concentrations of IFN-γ were also greater on average in bulls than heifers. Leukopenia occurred from 1 to 8h, with a decreased neutrophil to lymphocyte ratio for the first 5h among all calves. These data demonstrate the existence of a sexually dimorphic acute-phase response in pre-pubertal Brahman calves. Specifically, heifers may have a more robust acute response to LPS challenge, even though bulls display more signs of sickness.
authors.affiliation: USDA ARS Livestock Issues Research Unit, Lubbock, TX 79403, USA. Electronic address: jeff.carroll@ars.usda.gov.
authors.forename: Jeffery A
authors.initials: JA
authors.lastname: Carroll
authors.affiliation: USDA ARS Livestock Issues Research Unit, Lubbock, TX 79403, USA; Department of Animal Science, Texas AgriLife Research, Texas A&M University System, College Station, TX 77843, USA.
authors.forename: Nicole C
authors.initials: NC
authors.lastname: Burdick Sanchez
authors.affiliation: USDA ARS Livestock Issues Research Unit, Lubbock, TX 79403, USA; Department of Animal and Food Sciences, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Lindsey E
authors.initials: LE
authors.lastname: Hulbert
authors.affiliation: Department of Animal and Food Sciences, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Ballou
authors.affiliation: USDA ARS Livestock Issues Research Unit, Lubbock, TX 79403, USA.
authors.forename: Jeffery W
authors.initials: JW
authors.lastname: Dailey
authors.affiliation: Department of Animal Science, Texas AgriLife Research, Texas A&M University System, College Station, TX 77843, USA.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Caldwell
authors.affiliation: Brown Loam Branch Experiment Station, Mississippi State University, Raymond, MS 39154, USA.
authors.forename: Rhonda C
authors.initials: RC
authors.lastname: Vann
authors.affiliation: Department of Animal Science, Texas AgriLife Research, Texas A&M University System, College Station, TX 77843, USA.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Welsh
authors.affiliation: Texas AgriLife Research Center, Overton, TX 75684, USA.
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Randel
mesh_terms: D061605:Administration, Intravenous / Q000662:veterinary; D000818:Animals; D002417:Cattle / Q000276:immunology*; D005260:Female; D007113:Immunity, Innate / Q000187:drug effects* / Q000276:immunology; D007371:Interferon-gamma / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D012727:Sex Characteristics; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015850:Interleukin-6; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma
keywords: Cattle; Cortisol; Innate immunity; Lipopolysaccharide; Sexual dimorphism