Effect of litter size and birth weight on growth, carcass and pork quality, and their relationship to postmortem proteolysis.

The objective of the study was to test the hypothesis that birth weight (BtW) influences growth, carcass characteristics, meat quality, and postmortem (pm) proteolysis differently when pigs originate from small (S) or large (L) litters. Swiss Large White barrows (60) used in this study originated from 20 litters with either less than 10 (S) or more than 14 (L) piglets born per litter. Within each of the S and L litters, 3 barrows were selected at birth: the lightest (L-BtW), the heaviest (H-BtW), and the one with a BtW nearest to the average BtW of the litter (M-BtW). The BW and total feed intake of the individually penned pigs were determined weekly. At slaughter, carcass characteristics were assessed. Meat quality traits were determined in the LM and dark portion of semitendinosus muscle. Titin, nebulin, desmin, and integrin proteolysis were evaluated by SDS-PAGE and Western blot technique, and mu - and m-calpain activities were monitored using casein zymography. Litter size affected BtW of L-BtW and M-BtW but not of H-BtW barrows (BtW x litter size interaction; P = 0.07). From weaning to slaughter, L-BtW barrows grew slower (P < 0.01), ingested less feed (P < 0.01), and were less efficient (P < 0.01) than H-BtW and M-BtW barrows. The carcass yields were greater (P < 0.01), and livers and kidneys were lighter (P </= 0.01) in L-BtW compared with H-BtW barrows. Regardless of BtW, barrows from S litters had greater percentages of shoulder (P = 0.02) and lower percentages of omental fat (P = 0.06) than barrows from L litters. Compared with the LM of H-BtW barrows, the LM of L-BtW barrows was redder (P < 0.01). The semi-tendinosus muscle of M-BtW barrows was more (P < 0.01) tender than that of L-BtW and H-BtW barrows. The extent of titin and nebulin proteolysis at 24 and 72 h pm was greater (P </= 0.07) in the LM of H-BtW than in L-BtW barrows. At 72 h pm, integrin of the LM had been less (P = 0.08) degraded in barrows originating from S than from L litters. These results confirm the known effect of BtW on growth performance, whereas its effect on carcass characteristic and meat quality traits could only be partially demonstrated. Although litter size affected average BtW of the L-BtW and M-BtW barrows, its effect on growth performance, carcass characteristics, and meat quality was minor. The almost complete absence of significant BtW x litter size interaction indicates that litter size affects swine growth and carcass and meat quality through its inverse relationship with BtW.

[1]  M. Vestergaard,et al.  Basic principles of muscle development and growth in meat-producing mammals as affected by the insulin-like growth factor (IGF) system. , 2004, Domestic animal endocrinology.

[2]  S. T. Jiang.  Contribution of muscle proteinases to meat tenderization. , 1998, Proceedings of the National Science Council, Republic of China. Part B, Life sciences.

[3]  Guoyao Wu,et al.  Board-invited review: intrauterine growth retardation: implications for the animal sciences. , 2006, Journal of animal science.

[4]  L. Lefaucheur,et al.  Low birth weight is associated with enlarged muscle fiber area and impaired meat tenderness of the longissimus muscle in pigs. , 2006, Journal of animal science.

[5]  G. Geesink,et al.  Contribution of postmortem muscle biochemistry to the delivery of consistent meat quality with particular focus on the calpain system. , 2006, Meat science.

[6]  R M Robson,et al.  Effects of postmortem aging time, animal age, and sex on degradation of titin and nebulin in bovine longissimus muscle. , 1995, Journal of animal science.

[7]  D. Bauman,et al.  Ontogenic maturation of the somatotropin/insulin-like growth factor axis. , 1999, Journal of animal science.

[8]  E. Huff-Lonergan,et al.  Mechanisms of water-holding capacity of meat: The role of postmortem biochemical and structural changes. , 2005, Meat science.

[9]  G. Foxcroft.  Pre-natal Programming of Variation in Post-Natal Performance - How and When? , 2007 .

[10]  G. Bee.  Effect of early gestation feeding, birth weight, and gender of progeny on muscle fiber characteristics of pigs at slaughter. , 2004, Journal of animal science.

[11]  A. Fowden,et al.  The effects of birth weight and postnatal growth patterns on fat depth and plasma leptin concentrations in juvenile and adult pigs , 2004, The Journal of physiology.

[12]  M. Lawson.  The role of integrin degradation in post-mortem drip loss in pork. , 2004, Meat science.

[13]  E. Huff-Lonergan,et al.  Rate and extent of pH decline affect proteolysis of cytoskeletal proteins and water-holding capacity in pork. , 2007, Meat science.

[14]  K. Honikel,et al.  Reference methods for the assessment of physical characteristics of meat. , 1998, Meat science.

[15]  A. Chishti,et al.  Micro-calpain is essential for postmortem proteolysis of muscle proteins. , 2006, Journal of animal science.

[16]  W. Herzog,et al.  Effects of available dietary carbohydrate and preslaughter treatment on glycolytic potential, protein degradation, and quality traits of pig muscles. , 2006, Journal of animal science.

[17]  C. Rehfeldt,et al.  A second look at the influence of birth weight on carcass and meat quality in pigs. , 2008, Meat science.

[18]  T. Wheeler,et al.  Prerigor and postrigor changes in tenderness of ovine longissimus muscle. , 1994, Journal of animal science.

[19]  E. Huff-Lonergan,et al.  Proteolysis of specific muscle structural proteins by mu-calpain at low pH and temperature is similar to degradation in postmortem bovine muscle. , 1996, Journal of animal science.

[20]  W. G. Zhang,et al.  Contribution of postmortem changes of integrin, desmin and μ-calpain to variation in water holding capacity of pork. , 2006, Meat science.

[21]  P. Purslow,et al.  The effect of ageing on the water-holding capacity of pork: role of cytoskeletal proteins. , 2001, Meat science.

[22]  E. Huff-Lonergan,et al.  Early postmortem biochemical factors influence tenderness and water-holding capacity of three porcine muscles. , 2004, Journal of animal science.

[23]  D. E. Goll,et al.  The calpain system. , 2003, Physiological reviews.

[24]  C. Rehfeldt,et al.  Consequences of birth weight for postnatal growth performance and carcass quality in pigs as related to myogenesis. , 2006, Journal of animal science.

[25]  W Herzog,et al.  Free-range rearing of pigs during the winter: adaptations in muscle fiber characteristics and effects on adipose tissue composition and meat quality traits. , 2004, Journal of animal science.

[26]  L. Lefaucheur.  Myofiber typing and pig meat production , 2001 .

[27]  N. Stickland,et al.  Muscle cellularity and birth weight , 1987 .

[28]  N. Stickland,et al.  Muscle development in large and small pig fetuses. , 1983, Journal of anatomy.

[29]  J. Ketelslegers,et al.  Nutritional regulation of the insulin-like growth factors. , 1994, Endocrine reviews.

[30]  M. Père,et al.  Uterine blood flow in sows: effects of pregnancy stage and litter size. , 2000, Reproduction, nutrition, development.

[31]  N. Stickland,et al.  Sources of variation in myofibre number within and between litters of pigs , 1991 .

[32]  Nathalie Quiniou,et al.  Variation of piglets’ birth weight and consequences on subsequent performance , 2002 .

[33]  C. Putman,et al.  Number of conceptuses in utero affects porcine fetal muscle development. , 2004, Reproduction.

[34]  Y. Le Cozler,et al.  Influence of piglet birth weight on postnatal growth performance, tissue lipogenic capacity and muscle histological traits at market weight , 2005 .