Effects of metabolic changes produced in ewes with subclinical pregnancy toxemia over reproductive parameters

Abstract

The objective of this work was to determine the repercussion of the metabolic changes that occur in induced subclinical pregnancy toxemia in single-or twin-bearing ewes on the duration of gestation, type and length of lambing, and placental expulsion time. Fifty-one adult Corriedale ewes with a known gestation date and fed in the wild were randomly divided at day 145 of gestation into four groups. Group A included single-bearing ewes, and C twin-bearing ewes, all of which were fed ad libitum. Group B was composed of single-bearing ewes, and D of twin-bearing ewes, all subjected to a 75% feed restriction until glycemic values were compatible with subclinical pregnancy toxemia. Metabolic parameters were determined in all ewes from day 145 of gestation to 72 h postpartum. Likewise, the duration of gestation, type of lambing (eutocic/dystocic), labor length, and placental expulsion time were recorded. Glycemia and β-hydroxybutyrate values compatible with subclinical pregnancy toxemia were achieved after 48 h of feed restriction, being 30.67±2.37 mg/dL and 1.87±0.12 mmol/L in single-bearing ewes and 28.40±3.39 mg/dL and 2.21±0.42 mmol/L in twin-bearing ewes, respectively. It is concluded that subclinical pregnancy toxemia induced by feed restriction at the end of gestation, frequent situation that occurs in flock management, produces mild metabolic changes, which return to normal values after the delivery. These metabolic changes registered before lambing do not modify the gestation length, do not increase the percentage of dystocical deliveries, nor influence labor length or placental expulsion time.

Subclinical ovine gestational toxaemia at parturition: Influence on determinant variables in lamb survival

“…At the time when ewes in groups B and D reached glycaemia values indicative of subclinical gestational toxaemia (28. 62±4.33mg/dL;Cal Pereyra et al, 2015), they were removed from feed restriction and switched to pasture feeding with natural pasture (Abreu-Palermo et al, 2021).…”

“…At day 145 of gestation, prior to the start of feed restriction, glycaemia concentration did not show significant differences among the experimental groups (A = 50.53±1.68 mg/dL; B = 55.13±2.14 mg/dL, C = 57.17±2.67 mg/dL, and D = 51.27±2.73 mg/dL). The glycaemia concentration of ewes in groups B (single gestation) and D (twin gestation) decreased 12 h after the start of feed restriction (P<0.001), reaching glycaemia values indicative of subclinical gestational toxaemia 48 h after the start of treatment (B = 30.67±2.37 mg/dL and D = 28.40±3.39 mg/dL) (Table 1; Abreu-Palermo et al, 2021).…”

“…At day 145 of gestation, before starting feed restriction, BHB concentration did not show significant differences among experimental groups (A = 0.69±0.05 mmol/L, B = 0.47±0.07 mmol/L, C = 0.72±0.14 mmol/L, and D = 0.85±0.20 mmol/L). The serum BHB concentration of ewes in the groups subjected to feed restriction (groups B and D) showed an increase (P = 0.0001) 24 h after starting the treatment, reaching serum values of this ketone body indicative of subclinical gestational toxaemia 48 h after starting the treatment (B = 1.87±0.12 mmol/L and D = 2.21±0.42 mmol/L) (Table 1; Abreu-Palermo et al, 2021). The absence of uppercase or lowercase letters implies the lack of significant differences among times or groups.…”

“…The subclinical form of the disease is characterised by steadily increasing hypoglycaemia and hyperketonemia in dams in the absence of clinical signs (Barbagianni et al, 2015b;Cal-Pereyra et al, 2015;Marutsova and Marutsov, 2017). At the blood level it can be diagnosed when glycaemia values are between 24.29 and 32.95 mg/dL at which time the serum concentration of β-hydroxybutyrate (BHB) is between 1.23 and 3.29 mmol/L (Abreu-Palermo et al, 2021). However, the effect of subclinical gestational toxaemia on lamb survival is not known.…”

Colostrum traits and newborn body weight and growth: comparison between single and twin underfed sheep pregnancies

“…In well-nourished pregnant ewes, either carrying singletons or twin fetuses, blood glucose concentration range is around 29-59 mg/dL during gestation (21), and around 40-60 mg/dL near term (22). The values recorded in our study for maternal glycaemia 1 week before delivery were in the range to those previously described in animals under a severe nutritional restriction [sheep with only 25% of the daily ration for 24-48 h (22)] in which glycaemia decrease to around 41 and 28 mg/dL for single-and twin-bearing ewes, respectively. Blood glucose content in our study increased in the peripartum to more than 3-fold higher than 1 week before parturition, again without differences due to the type of parturition.…”