Adrenal and ovarian function in nutritionally-restricted or Acacia berlandieri-fed Angora goats

Abstract

Mature Angora nannies (31[]1.1 kg body weight; BW) were randomly assigned to one of four dietary regimens over a 60-d period to evaluate the effects of nutritional restriction (high and low energy diets) and Acacia berlandieri (guajillo) on ovarian and adrenal function. Diets consisted of: 1) 3.6% BW of a pelleted (HC, n=9); 2) 2% BW of the some diet (LC, n=9); 3) diet 2 with ad-lib guajillo (HG, n=10); or 4) 1% BW of the diet with ad-lib guajillo (LG, n=10). Intake of guajillo was measured daily and body weights were obtained weekly. Pituitary, anterior pituitary, and paired adrenal weight did not differ among treatments nor did total adrenal area, adrenomedullary area, and adrenocortical area. Concentrations of cortical were higher (P[]0.05) in the HG group (10.65[]1.16 ng/mL) compared to HC, LC, and LG groups (6.87[].85, 5.99[].55, and 7.29[].58 ng/mL respectively). Addition of synthetic ACTH (10 and 100 pg/mL) to adrenocortical incubation increased medium content of consul for all groups except HG with the greater response (P[]0.02) noted for HC goats. Based on profiles of plasma concentration of progesterone and estrus detection data, estrous cycle length was shorter (P<0.05) for HG (18.9 [] .4 days) compared to HC (20.0[].3 days) goats. Ovarian weight was significantly greater in HG (5.34[].33g) compared to LC (3.34[].33g) and HC (4.34[].35g) but not the LG (4.18[].33 g) group. Follicular fluid weight was greater (P<.0.05) for HG (1.78[].15 g) relative to other treatment groups (range; 1.03[].15 g to 1.25[].15 g). Ovarian stromal weight was greater (P<0.05) for HG compared to LG and LC but was similar to that of the HC group. Corpora luted progesterone content ([]g/100 mg) for HG (2.22[].35) and LC (2.81[].39) were higher (P<0.02) than for the HC (.78[].23) and LG (1.16[].31) groups. There were no significant differences in CL StAR P450scc protein content. Uterine weight was greater (P<0.05) for HG compared to the other groups. These data suggest that nutritional supplementation enabled goats consuming guajillo to avoid some detrimental effects of guajillo, and guajillo consumption enabled nutritionally restricted goats to avoid some detrimental effects of undernutrition.