Effects of subclinical pregnancy toxemia on immune responses in sheep.
OBJECTIVE
To determine the effects of moderate feed restriction, single or twin pregnancy, and subclinical pregnancy toxemia (PT) on immune responses of ewes.


METHODS
16 Sardinian ewes.


METHODS
Six weeks before lambing, ewes were assigned to 1 of 2 groups (n = 8/group) matched for number of fetuses, body condition score, and plasma glucose, non-esterified fatty acids (NEFA), and beta hydroxybutyrate (BHBA) concentrations, and feed intake was restricted for 1 of the groups. Cell-mediated immunity was evaluated in vivo and in vitro. Humoral immunity was evaluated in vivo by determining production of IgG antibodies against keyhole limpet hemocyanin (KLH).


RESULTS
Four ewes developed subclinical PT (plasma BHBA concentration > 0.86 mmol/L without any clinical signs of disease). Whether feed was restricted and type of pregnancy (single vs twin) did not have any significant effects on cell-mediated and humoral immune responses. Ewes with subclinical PT had significantly lower in vitro proliferation of phytohemagglutinin-stimulated peripheral blood mononuclear cells and significantly lower values for KLH-specific IgG than did healthy ewes. Plasma BHBA and NEFA concentrations were negatively correlated with in vitro proliferation of peripheral blood mononuclear cells; plasma NEFA concentration was negatively correlated with values for KLH-specific IgG.


CONCLUSIONS
Results suggest that subclinical PT may be associated with impairments in cell-mediated and humoral immune responses in sheep.
Lacetera
N
N
Istituto di Zootecnia, Università degli Studi della Tuscia, Viterbo, Italy.
Bernabucci
U
U
Ronchi
B
B
Nardone
A
A
D020155:3-Hydroxybutyric Acid / Q000097:blood; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005508:Food Deprivation / Q000502:physiology; D006433:Hemocyanins / Q000276:immunology; D007074:Immunoglobulin G / Q000097:blood; D016018:Least-Squares Analysis; D009752:Nutritional Status / Q000276:immunology / Q000502:physiology; D010835:Phytohemagglutinins / Q000276:immunology; D011225:Pre-Eclampsia / Q000097:blood / Q000276:immunology / Q000662:veterinary*; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000276:immunology / Q000502:physiology; D012756:Sheep / Q000097:blood / Q000276:immunology* / Q000502:physiology; D012885:Skinfold Thickness
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007074:Immunoglobulin G; D010835:Phytohemagglutinins; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin; D020155:3-Hydroxybutyric Acid