title: Sustained delivery of exogenous melatonin influences biomarkers of oxidative stress and total antioxidant capacity in summer-stressed anestrous water buffalo (Bubalus bubalis).
abstract: High ambient temperature during summer in tropical and subtropical countries predisposes water buffaloes (Bubalus bubalis) to develop oxidative stress having antigonadotropic and antisteroidogenic actions. Melatonin is a regulator of seasonal reproduction in photoperiodic species and highly effective antioxidant and free radical scavenger. Therefore, a study was designed to evaluate the effect of sustained-release melatonin on biomarkers of oxidative stress i.e., the serum malondialdehyde (MDA) and nitric oxide (NO), and the total antioxidant capacity (TAC). For the study, postpartum buffaloes diagnosed as summer anestrus (absence of overt signs of estrus, concurrent rectal examination, and RIA for serum progesterone) were grouped as treated (single subcutaneous injection of melatonin at 18 mg/50 kg body weight dissolved in sterilized corn oil as vehicle, n = 20) and untreated (subcutaneous sterilized corn oil, n = 8). Blood sampling for estimation of serum TAC and MDA (mmol/L) and NO (μmol/L) was carried out at 4 days of interval from 8 days before treatment till 28 days after treatment or for the ensuing entire cycle length. Results showed serum TAC concentration was higher in the treatment group with a significant (P < 0.05) increasing trend, whereas MDA and NO revealed a significant (P < 0.05) decline. Serum MDA and NO were higher in control compared with those of treatment group. Moreover, buffaloes in the treatment group showed 90% estrus induction with 18.06 ± 1.57 days mean interval from treatment to the onset of estrus. These results report that melatonin has a protective effect by elevating antioxidant status and reducing oxidative stress resulting in the induction of cyclicity in summer-stressed anestrous buffaloes.
authors: Division of Animal Reproduction, ICAR Res Complex for NEH Region, Umiom, Meghalaya, India.
authors: Ashok
authors: A
authors: Kumar
authors: AI Laboratory, LPM, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India.
authors: S
authors: S
authors: Mehrotra
authors: Division of Climatology and Physiology, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India.
authors: G
authors: G
authors: Singh
authors: AI Laboratory, LPM, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India.
authors: K
authors: K
authors: Narayanan
authors: Division of Animal Reproduction, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India.
authors: G K
authors: GK
authors: Das
authors: Semen Freezing Laboratory, Central Institute for Research on Cattle, Meerut, Uttar Pradesh, India.
authors: Y K
authors: YK
authors: Soni
authors: Division of Animal Reproduction, ICAR Res Complex for NEH Region, Umiom, Meghalaya, India.
authors: Mahak
authors: M
authors: Singh
authors: Division of Animal Reproduction, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India.
authors: A S
authors: AS
authors: Mahla
authors: Semen Freezing Laboratory, Central Institute for Research on Cattle, Meerut, Uttar Pradesh, India. Electronic address: sangnee15@gmail.com.
authors: N
authors: N
authors: Srivastava
authors: Division of LE, Statistics and IT, Indian Veterinary Research Institute, Izatnagar, UP, India.
authors: M R
authors: MR
authors: Verma
mesh_terms: D000780:Anestrus / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002020:Buffaloes / Q000378:metabolism*; D005260:Female; D018869:Heat-Shock Response; D008315:Malondialdehyde / Q000097:blood; D008550:Melatonin / Q000494:pharmacology*; D009569:Nitric Oxide / Q000097:blood; D018384:Oxidative Stress; D012621:Seasons
chemical_list: D000975:Antioxidants; D009569:Nitric Oxide; D008315:Malondialdehyde; D008550:Melatonin
keywords: Free radical; Malondialdehyde; Nitric oxide; Oxidative stress; Reactive oxygen species