Clinical, ultrasonographic, bacteriological, cytological and histological findings during uterine involution in ewes with pregnancy toxaemia and subsequent reproductive efficiency

Effect of Enhanced Uterine Involution on Reproductive Performance in Multiparous Ewes

Rapid uterus involution is essential for minimising interpartum intervals, enhancing reproductive performance, and optimising production in ewes. This study aimed to accelerate the uterine involution of postpartum ewes through a relatively simple hormone treatment approach. In this study, 96 Dorper × Hu F1 ewes were assigned to three groups. The ewes were subsequently injected with normal saline (control group), prostaglandin + oxytocin (PG + OT group) and prostaglandin + oxytocin + horse chorionic gonadotropin (PG + OT + eCG group). Each group had 16 ewes producing a single lamb and 16 ewes producing twin lambs used to determine the effects of different treatments on their uterine involution and reproductive performance. PG + OT + eCG treatment accelerated the rate of uterine horn involution of single lambs (21.40 ± 0.89 days vs. 30.66 ± 1.03 days, p < 0.05) and twin hlambs (22.2 ± 1.09 days vs. 30.33 ± 0.81 days, p < 0.05) compared to the control group. PG + OT + eCG treatment also accelerated the regression of the uterine wall serosa structure and the removal of uterine effusion compared to PG + OT treatment, whose effect was moderate. PG + OT and PG + OT + eCG treatments had no significant effect on the recovery of the maximum uterine diameter of single and double lambing ewes compared to the control group. However, both treatments shortened the first estrus time of postpartum ewes (53.73 ± 3.69 days vs. 48.06 ± 5.87 days vs. 46.46 ± 7.41 days, p > 0.05). There was no significant difference in the conception rate among groups (p > 0.05). Notably, the change trend of reproductive hormones in postpartum ewes was consistent. PG + OT and PG + OT + eCG treatments significantly increased the concentration of estradiol and follicle-stimulating hormone during uterine involution (p < 0.05), but inhibited the secretion of progesterone compared to the control group. The peak of the luteinising hormone in the two treatment groups appeared 14 days earlier compared to that of the control group. In summary, exogenous PG + OT + eCG increases the concentration of estradiol during uterine involution, inhibits the secretion of progesterone, and accelerates the postpartum uterine involution and postpartum estrus time of ewes. These findings provide a basis for exploring the mechanism of uterine involution in sheep and improving sheep production efficiency.

Alterations in the uterine echotexture, hemodynamics, and histological findings in relation to metabolomic profiles in goats with different ovarian activities (active versus inactive ovaries)

This study investigated, for the first time, the alterations in the uterine echotexture and blood flow in cyclic and acyclic (inactive ovary) goats using ultrasonography. The study aimed also to evaluate the metabolomic changes in the plasma of cyclic and acyclic goats. Furthermore, the histopathological approach was applied to the specimens of the uterus to validate the findings of this study. Based on monitoring the estrous cyclicity, goats were assigned into either a cyclic group or an acyclic one (n = 7, each). Ovarian morphometry and hemodynamics were assessed to confirm group assignment. Full ultrasonographic examinations were performed to assess the uterine echotexture by B-mode ultrasonography and uterine hemodynamics by color Doppler ultrasonography in the cyclic group (at days 10-12) and acyclic group. Additionally, blood samples were withdrawn for measuring hormonal concentrations and for metabolomics analysis. Specimens of the uterus were executed for histopathological evaluation in both groups. Results revealed alterations in the uterine hemodynamics and endometrial echotexture. Goats in the cyclic group attained a significantly higher color pixel area of the endometrium compared to those in the acyclic one (P< 0.001). However, the pixel intensity of the endometrium echotexture was significantly (P< 0.05) lower in the cyclic group than in the smooth inactive ovary one. There were significant (P< 0.05) increases in the concentrations of FSH, LH, and inhibin in the cyclic group compared to their concentrations in the acyclic one. Goats in the acyclic group attained noticeable (P< 0.001) lower concentrations of E2 and P4 than in the cyclic goats. The metabolomic results revealed the existence of several up- and down-regulated metabolites among the studied groups. In this investigation, untargeted metabolomic analysis revealed the existence of 5 up-regulated metabolites (ketoleucine, L-fucose, D-glucurono-6,3-lactone, melatonin, and 5-methoxy tryptamine) and 5 down-regulated ones (p-octopamine, 3-hydroxyisovaleric acid, methylmalonic acid, 4-hydroxyphenylpyruvic acid, and cadaverine) in the cyclic group compared to the acyclic one. The enrichment analysis of the significant metabolites showed top pathways that may be involved in these changes, such as fructose and mannose metabolism, valine. Leucine, and isoleucine biosynthesis, linoleic acid metabolism, arginine biosynthesis, and vitamin B6 metabolism based on the KEGG enriched pathway. Altogether, the histopathological assessment showed noticeable changes in the columnar epithelial lining of the endometrial epithelium, endometrial vascularity, and endometrial glands among the studied groups. In conclusion, this study extrapolated the differences between cyclic goats (during the mid-luteal phase) and acyclic ones in terms of hormonal, hemodynamics, echotexture of the uterus, and circulating metabolomics. These findings are very crucial to fully assess the fertility potential in goats.

Incorporation of L-Carnitine in the OvSynch protocol enhances the morphometrical and hemodynamic parameters of the ovarian structures and uterus in ewes under summer climatic conditions

Heat stress negatively impacts the reproductive performance of sheep including the efficiency of estrous synchronization regimens. This study aimed to investigate the potential effects of L-Carnitine (LC) administration on the efficacy of the OvSynch protocol in ewes under summer climatic conditions. Ewes were synchronized for estrus using the OvSynch protocol and a dose of LC (20 mg/kg body weight) was intravenously (IV) administered on the same day of PGF2α injection to one group (n = 8; LC group), while other ewes (n = 8; control group) received the same protocol without LC. Ultrasonographic evaluation (including B-mode, color, and pulsed Doppler) was used to assess the morphometrical and hemodynamic parameters of ovarian structures [number, size, and blood flow of follicles (GFs) and corpora lutea (CLs)] and uterus during the estrous phase (Day 0), and on Day 8 post ovulation (luteal phase). Uterine artery blood flow (MUA) was assessed by measuring the resistive index (RI) and pulsatility index (PI) at both stages. The serum samples were collected to measure the concentrations of estradiol (E2), progesterone (P4), and total antioxidant capacity (TAC) using commercial kits. Results revealed a significant (P<0.05) increase in the colored pixel area of GFs and uterus in the LC group (392.84 ± 31.86 and 712.50 ± 46.88, respectively) compared to the control one (226.25 ± 17.74 and 322 ± 18.78, respectively) during Day 0. Circulating E2 and TAC levels were significantly (P<0.05) higher in the LC-treated ewes (31.45 ± 1.53 pg/ml and 1.80 ± 0.13 mM/L, respectively) compared to those in the control ewes (21.20 ± 1.30 pg/ml and 0.98 ± 0.09 mM/L, respectively) during Day 0. Moreover, LC improved the colored pixel area of CLs (2038.14 ± 102.94 versus 1098 ± 82.39) and uterus (256.38 ± 39.28 versus 121.75 ± 11.36) and circulating P4 (2.99 ± 0.26 ng/ml versus1.67 ± 0.15 ng/ml) on Day 8. Values of RI of MUA were significantly lower in the LC group compared to the control one on Day 0 and Day 8 (0.48 ± 0.03 versus 0.72 ± 0.03 and 0.58 ± 0.03 versus 0.78 ± 0.02, respectively). In conclusion, LC incorporation in the OvSynch protocol enhanced the morphometrical and hemodynamic parameters of the ovarian structures and the uterus concomitantly with improvements in the TAC, E2, and P4 concentrations in ewes under hot summer conditions.

Pregnancy Toxemia Therapeutic Options

This review covers the treatment options for pregnancy toxemia in small ruminants. Clinical assessment and detection of underlying metabolic and electrolyte derangements direct resuscitation efforts and provide prognostic indications. Treatment programs are dependent on producer goals and case specifics. Options include oral glucogenic precursors (eg, propylene glycol, glycerol), intravenous glucose solutions, insulin, and other supportive care measures. Induction of parturition or C-section is often carried out to minimize ongoing energy deficits, with variable survival rates. Prolonging gestation to maximize fetal viability often requires intensive care in a hospital setting and carries significant risk to both dam and offspring.

Mortality of Dairy Sheep during the Peri-Parturient Period: Results of a Field Investigation in Greece

Simple Summary

The paper presents a field investigation into the death of ewes around the peri-parturient (lambing) period. The problem is financially important because, in such cases, the capital (i.e., the ewes) is lost along with the increased expenses incurred by farmers during gestation. The problem was found to occur sporadically. Most cases of death occurred before lambing. Pregnancy toxaemia, an important metabolic disease, was the clinical problem most often associated with peri-parturient death. Factors found to be significantly associated with occurrence of the problem included the average lambing rate, the season of the year during which the lambing period took place, and the number of animals in the flock.

Abstract

Objectives of the study were (a) to investigate the incidence risk of peri-parturient mortality in dairy flocks in Greece, (b) to study when such mortality occurs in relation to lambing, (c) to identify clinical problems associated with the deaths, and (d) to evaluate potentially associated factors. The deaths of ewes during the peri-parturient period (10 days before to 7 days after lambing) were monitored in 60 flocks over two years. In the ewes that died, detailed post-mortems were performed. The incidence risk of peri-parturient deaths was 0.7%. The daily incidence rate of deaths before, at, and after lambing was 0.05, 0.04, and 0.03%, respectively. Clinical problems most frequently associated with peri-parturient deaths were pregnancy toxaemia, ruminal acidosis and post-partum genital problems. For the occurrence of peri-parturient deaths in flocks, the average lambing rate in the flocks was the only significant factor. Regarding deaths before or after lambing, the season during which lambing took place and the number of animals in the flock, respectively, were found to be significant. Most ewes (54.5%) that died at lambing (dystocia) were primigravidae.