Summary: To determine the effect of undernutrition on embryo production and quality in superovulated sheep, 45 ewes were allocated into two groups to be fed diets that provided 1.5 (control, C; n = 20) or 0.5 (low nutrition, L; n = 25) times daily requirements for maintenance, from oestrous synchronization with intravaginal sponges to embryo collection. Embryos were collected 7 days after the onset of oestrus (day 0). Low nutrition resulted in lower live weight and body condition at embryo collection (P < 0.05). Diet (P < 0.01) and day of sampling (P < 0.001) significantly affected plasma non-esterified fatty acid (NEFA) and insulin concentrations. Plasma leptin concentrations decreased on day 7 only in L ewes. A significant effect of dietary treatment (P < 0.05) and day (P < 0.0001) was observed on plasma insulin-like growth factor (IGF)-I concentrations. The number of recovered oocytes and embryos did not differ between the groups (L: 15.4 ± 0.4; C: 12.4 ± 0.4). Recovery rate was lower (P < 0.05) in the L (60%) than in the C group (73%). The total number of embryos and number of viable-transferable embryos (5.0 ± 0.3 and 3.4 ± 0.3 embryos, respectively) of the L group were lower (P < 0.1) when compared with controls (8.4 ± 0.4 and 6.2 ± 0.4 embryos, respectively). Undernutrition during the period of superovulation and early embryonic development reduced total and viable number of embryos. These effects might be mediated by disruption of endocrine homeostasis, oviduct environment and/or oocyte quality.

For the conclusive diagnosis of Cushing's Syndrome, a stimulating ACTH test or a low suppressive Dexamethasone test is used. Reports in other species than the dog indicate that plasma cortisol concentration after ACTH administration is affected by gender. We investigated the effect of gender on the cortisol response to ACTH and Dexamethasone tests in dogs.

Background: The objective of this study was to determine whether an ACTH-induced increase in serum cortisol affects hematological variables and serum serotonin concentration in healthy dogs. Methods: Eight healthy dogs were evaluated using a randomized crossover design. Each dog received either ACTH (5 µg/kg, i.v.) or saline solution during the first experimental period and the alternate treatment after a 15-day interval, so that all dogs underwent both treatments. Blood samples were collected during the first 5 h after treatment. Serum cortisol and serotonin concentrations and hematological variables were determined. Results: ACTH-treated dogs showed higher serum cortisol concentrations than controls (p = 0.0002). ACTH treatment increased white blood cell and absolute neutrophil counts (p < 0.05), whereas the percentage of lymphocytes decreased at 120 min (p < 0.05), with no significant effects on the remaining hematological variables. ACTH treatment did not affect serum serotonin concentrations. Conclusions: This study shows that ACTH-induced increases in cortisol affected selected hematological variables in healthy dogs, including increased white blood cell and absolute neutrophil counts and a reduced percentage of lymphocytes, although all values remained within the reference interval. In contrast, ACTH-induced cortisol increases did not acutely affect serum serotonin concentrations during the first 300 min after treatment.