title: Changes in expression of monocarboxylate transporters, heat shock proteins and meat quality of Large White Yorkshire and Ghungroo pigs during hot summer period.
abstract: OBJECTIVE
  Present study explores the effect of hot summer period on the glycolytic rate of early post-mortem meat quality of Ghungroo and Large White Yorkshire (LWY) pig and comparative adaptability to high temperature between above breeds by shifting the expression of stress related genes like mono-carboxylate transporters (MCTs) and heat shock proteins (HSPs).
  
  
  METHODS
  Healthy pigs of two different breeds, viz., LYW and Ghungroo (20 from each) were maintained during hot summer period (May to June) with a mean temperature of about 38°C. The pigs were slaughtered and meat samples from thelongissimus dorsi(LD) muscles were analyzed for pH, glycogen and lactate content and mRNA expression. Following 24 h of chilling, LD muscle was also taken from the carcasses to evaluate protein solubility and different meat quality measurements.
  
  
  RESULTS
  LWY exhibited significantly (p<0.01) higher plasma cortisol and lactate dehydrogenase concentration than Ghungroo indicating their higher sensitivity to high temperature. LD muscle from LWY pigs revealed lower initial and ultimate pH values and higher drip loss compared to Ghungroo, indicating a faster rate of pH fall. LD muscle of Ghungroo had significantly lower lactate content at 45 min postmortem indicating normal postmortem glycolysis and much slower glycolytic rate at early postmortem. LD muscle of LWY showed rapid postmortem glycolysis, higher drip loss and higher degrees of protein denaturation. Ghungroo exhibited slightly better water holding capacity, lower cooking loss and higher protein solubility. All HSPs (HSP27, HSP70, and HSP90) and MCTs (MCT1, MCT2, and MCT4) in the LD muscle of pigs inclined to increase more in Ghungroo than LWY when exposed to high temperature.
  
  
  CONCLUSIONS
  Effect of high temperature on the variation of HSPs and MCTs may play a crucial role in thermal tolerance and adaptation to different climatic conditions, pH regulation, muscle acidification, drip loss, protein denaturation and also in postmortem meat quality development.
authors.affiliation: Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, Kolkata 700 037, India.
authors.forename: Thulasiraman
authors.initials: T
authors.lastname: Parkunan
authors.affiliation: Eastern Regional Station, ICAR-Indian Veterinary Research Institute, Kolkata-700037, India.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Das
authors.affiliation: Department of Veterinary Physiology, Faculty of Veterinary and Animal Sciences, Kolkata 700 037, India.
authors.forename: Dipak
authors.initials: D
authors.lastname: Banerjee
authors.affiliation: Eastern Regional Station, ICAR-Indian Veterinary Research Institute, Kolkata-700037, India.
authors.forename: Niharika
authors.initials: N
authors.lastname: Mohanty
authors.affiliation: Physiology & Climatology Division, ICAR-Indian Veterinary Research Institute, Bareilly, UP 243 122, India.
authors.forename: Avishek
authors.initials: A
authors.lastname: Paul
authors.affiliation: Eastern Regional Station, ICAR-Indian Veterinary Research Institute, Kolkata-700037, India.
authors.forename: P K
authors.initials: PK
authors.lastname: Nanda
authors.affiliation: Eastern Regional Station, ICAR-Indian Veterinary Research Institute, Kolkata-700037, India.
authors.forename: T K
authors.initials: TK
authors.lastname: Biswas
authors.affiliation: Eastern Regional Station, ICAR-Indian Veterinary Research Institute, Kolkata-700037, India.
authors.forename: Syamal
authors.initials: S
authors.lastname: Naskar
authors.affiliation: Physiology & Climatology Division, ICAR-Indian Veterinary Research Institute, Bareilly, UP 243 122, India.
authors.forename: Sadhan
authors.initials: S
authors.lastname: Bag
authors.affiliation: Physiology & Climatology Division, ICAR-Indian Veterinary Research Institute, Bareilly, UP 243 122, India.
authors.forename: Mihir
authors.initials: M
authors.lastname: Sarkar
authors.affiliation: National Research Centre on Pig, Rani Road, Guwahati, Assam 781131, India.
authors.forename: Narayana H
authors.initials: NH
authors.lastname: Mohan
authors.affiliation: Eastern Regional Station, ICAR-Indian Veterinary Research Institute, Kolkata-700037, India.
authors.forename: Bikash Chandra
authors.initials: BC
authors.lastname: Das
keywords: Ghungroo Pig; Glycolytic Rate; Heat Shock Proteins (HSPs); Large White Yorkshire; Meat Quality; Mono-carboxylate Transporters (MCTs); Summer Stress