EFFECTS OF L-CARNOSINE ON THERMOREGULATORY RESPONSES, HAEMATO-BIOCHEMICAL AND ELECTROCARDIOGRAPHIC CHANGES IN PREGNANT AND PERIPARTURIENT YANKASA EWES AND LAMBS DURING THE DRY SEASON

  • : Ms Word, Ms Word Format
  • : 55 Pages
  • : ₦3000
  • : 1-5 Chapters
  •  
  • Click to DOWNLOAD Materials

EFFECTS OF L-CARNOSINE ON THERMOREGULATORY RESPONSES, HAEMATO-BIOCHEMICAL AND ELECTROCARDIOGRAPHIC CHANGES IN PREGNANT AND PERIPARTURIENT YANKASA EWES AND LAMBS DURING THE DRY SEASON

Abstract:

The aim of the study was to investigate effects of L-carnosine administration on gestational thermoregulatory responses, haemato-biochemical, electrocardiographic and oxidative stress changes in Yankasa ewes during the dry season. Ewes were synchronised and bred, such that each gestation phase coincided with different periods of the dry-season; early-gestation (cold-dry/harmattan; day 25), mid-gestation (peak hot-dry; day 75), late-gestation (late hot-dry; days 125), periparturient period (late-hot dry). The Yankasa ewes used for the study consisted of non-pregnant (n = 10), pregnant (n = 10) and pregnant + L-carnosine (n = 10). Rectal temperature (RT), respiratory rate (RR), heart rate (HR) and electrocardiographic (ECG) parameters were evaluated in the pregnant and non-pregnant ewes. Haemato-biochemical changes were obtained in the pregnant ewes were during the gestation and periparturient period. Physiological parameters of the ewes were recorded concurrently with dry-(DBT) and wet-bulb (WBT) temperatures at the experimental site, thrice, two days apart during middle of each gestation phase at 06:00 h, 14:00 h and 18:00 h. Subsequently, starting from three weeks prepartum until parturition, L-carnosine was administered to pregnant ewes at 100 mg/kg per osdaily at 06:00 h.While, 10 mL of water (per os) was administered to the control group during the same period. The physiological parameters and blood samples were obtained at weeks 2and 1prepartum, and postpartum from ewes and their lambs to determine the effect of L-carnosine. There was a significant (P < 0.001) fluctuation in RT values regardless of the ewe‟s physiological status during the dry-seasons. The RT and RR were higher (P < 0.05) in pregnant than non-pregnant ewes at mid-gestation (39.04 ± 0.05℃vs 38.83 ± 0.06℃)and late-gestation (56.93 ± 2.76 breaths/minute vs 48.15 ± 2.10 breaths/minute), respectively. The RT was lower (P < 0.001) at 06:00 h during the cold-dry season in pregnant ewes at early-gestation than in non-pregnant ewes (36.72 ± 0.08 ℃vs 37.22 ± 0.11 ℃). The dry-bulb temperature positively correlated with RT and RR during xxvi different gestation stages, while the temperature-humidity index was significantly (P < 0.05) correlated with RR, except in non-pregnant ewes during early-gestation.Electrocardiographic intervals of RR and QT were significantly (P < 0.05) shorter in pregnant than in non-pregnant ewes during gestation. Packed cell volume (PCV), red blood cell (RBC) count andserum free fatty acids were significantly higher at mid-gestation compared to week 2 prepartum. Neutrophil count and urea concentration were significantly (P < 0.05) higher at parturition compared to mid-gestation and early-gestation, respectively. The AST and ALT activities were significantly (P < 0.05) higher during gestation compared to postpartum.The malondialdehyde (MDA) concentration was significantly (P < 0.05) higher at mid-gestation than at parturition and week 1 postpartum (1.55 ± 0.06 μmol/mL vs 1.25 ± 0.08 μmol/mL and 1.17 ± 0.04 μmol/mL), while the 8-isoprostane concentration was significantly (P < 0.05) higher at late-gestation compared to pre-gestation, weeks 2 and 3 postpartum (148.90 ± 1.17 IU/mL vs 138.30 ± 1.73 IU/mL, 138.40 ± 2.46 IU/mL, 137.60 ± 1.89 IU/mL, respectively). However, the concentration of triiodothyronine (0.76 ± 0.07 ng/mL vs 1.16 ± 0.09 ng/mL), and activities of catalase (46.17 ± 1.34 IU/mL vs 53.17 ± 0.75 IU/mL) and glutathione peroxidase (GPx) (43.00 ± 0.93 IU/mL vs 49.33 ± 1.20) were lower (P < 0.05) at mid-gestation than week 1 postpartum.Haemoglobin concentration, RBC, lymphocyte count, urea concentration and ALT activities were significantly (P < 0.05) higher in lambs than the dams postpartum. Conversely, neutrophil count was lower in lambs than the dams postpartum. Electrocardiographic intervals of RR and QT were significantly (P < 0.05) shorter in lambs than their dam, while the heart rate was higher in lambs than their dams. Aspartate aminotransferase activity (39.83 ± 1.87 IU/L vs 46.86 ± 1.12 IU/L; P < 0.05) and triglyceride concentrations (0.80 ± 0.06 mmol/L vs 0.99 ± 0.07 mmol/L, P < 0.05) were lower in pregnant + L-carnosine than untreated pregnant ewes during 3rd week of treatment and triglyceride concentration at 1st week of treatment prepartum. Serum malondialdehyde(1.2 ± 0.08 xxvii μmol/mL vs 1.47 ± 0.05 μmol/mL; P < 0.05) and 8-isoprostane concentrations (139.3 ± 0.9 ng/L vs 145.4 ± 2.24 ng/L; P < 0.05) were lower, while activities of catalase (53.17 ± 0.91 IU/mL vs 48.00 ± 1.24 IU/mL; P < 0.05) and glutathione peroxidase (GPx) activities were higher (49.71 ± 1.63 IU/mL vs 44.43 ± 1.15 IU/mL; P < 0.05) in pregnant + L-carnosine ewes, compared to pregnant untreated ewes. In conclusion, Yankasa ewes were able to maintain RT within physiological ranges, but this was at expense of increased RR. In addition, there was a concomitant effects of gestation and ambient temperature on thermoregulatory responses, haemato-biochemical and biomarkers of oxidative stress. Furthermore, the study showed that L-carnosine reduced MDA, 8-isoprostane and triglyceride concentrations, and augmented the antioxidant activities in prepartumYankasa ewes during the dry season.

EFFECTS OF L-CARNOSINE ON THERMOREGULATORY RESPONSES, HAEMATO-BIOCHEMICAL AND ELECTROCARDIOGRAPHIC CHANGES IN PREGNANT AND PERIPARTURIENT YANKASA EWES AND LAMBS DURING THE DRY SEASON

Sharing is caring!

Leave a Reply