Performance and carcass characteristics of intact and castrated male Black goat kids fed diets of various energy levels

Thirty Black goat male kids were used in a 3 × 2 factorial arrangement to evaluate the effects of three dietary energy levels (EL) and early castration (TRT) on growth performance, body and carcass characteristics. Upon weaning at 90 days of age, kids were randomly divided into three equal groups (n = 10: five intact and five castrated) and assigned to one of the three dietary treatments containing 15% CP and different energy levels: low (LEL; 10.44 MJ ME/kg DM), medium (MEL; 11.60 MJ ME/kg DM) and high energy (HEL; 12.90 MJ ME/kg DM). Kids were individually fed on an ad libitum basis and were slaughtered at the end of the fattening period. Results showed no differences between castrated and intact kids in feed and nutrient intake. The level of dietary energy affected dry matter intake (P < 0.05), metabolisable energy intake (P < 0.01), crude protein intake (P < 0.05), neutral detergent fibre (P < 0.001) and acid detergent fibre intakes (P < 0.001). Dry matter intake was 280, 305 and 264 g/kg W0.75.day for kids receiving LEL, MEL and HEL diets, respectively. Metabolisable energy intake was the highest for kids receiving the MEL diet (0.90 Mcal/kg W0.75.day) compared with LEL (0.73 Mcal/ kg W0.75.day) and HEL (0.88 Mcal/kg W0.75.day) diets. Final liveweight and average daily gain (ADG) were greater (P < 0.01) in MEL diets. Kids fed MEL gained 133 g/day, while ADG values were 92 and 100 g/day for kids fed LEL and HEL diets, respectively. Total muscle percentage was greater (P < 0.05) for kids fed MEL diets (55.9%) compared with LEL (53.8%) and HEL (51.1%) diets. Castrated kids had lower (P < 0.01) carcass muscle percentage, but higher carcass (P < 0.01) and subcutaneous (P < 0.001) fat percentages than intact kids. It can be concluded that the best growth performance was observed in kids receiving the MEL with no differences between castrated and intact kids. Castration influenced accretion of fat in castrated kids.

[1]  S. G. Haddad,et al.  Effects of castration on growth performance and carcass characteristics of Awassi lambs fed high concentrate diet , 2006 .

[2]  G. Kannan,et al.  Meat quality in goats as influenced by dietary protein and energy levels, and postmortem aging , 2006 .

[3]  C. Lu,et al.  Performance of Omani goats fed diets containing various metabolizable energy densities , 2005 .

[4]  S. G. Haddad.  Effect of dietary forage:concentrate ratio on growth performance and carcass characteristics of growing Baladi kids , 2005 .

[5]  L. Hoffman,et al.  Production efficiency of South African Mutton Merino lambs and Boer goat kids receiving either a low or a high energy feedlot diet , 2003 .

[6]  P. Murray,et al.  Part 1. Growth, carcass and meat quality parameters of male goats: effects of genotype and liveweight at slaughter , 2003 .

[7]  M. Khan,et al.  Effect of Dietary Energy Supplementation on Feed Intake, Growth and Reproductive Performance of Goats under Grazing Condition , 2003 .

[8]  I. Balde,et al.  Carcass characteristics of West African dwarf goats under extensive system , 2001 .

[9]  Karim,et al.  Growth performance of Malpura and crossbred lambs under intensive feeding. , 2000, Small ruminant research : the journal of the International Goat Association.

[10]  Mahgoub,et al.  Effects of dietary energy density on feed intake, body weight gain and carcass chemical composition of Omani growing lambs. , 2000, Small ruminant research : the journal of the International Goat Association.

[11]  O. Mahgoub,et al.  Effect of method and time of castration on growth and carcass characteristics of Omani sheep , 1998 .

[12]  A. Abdullah,et al.  Patterns of change with growth for muscularity and other composition characteristics of Southdown rams selected for high and low backfat depth. , 1998 .

[13]  G. Garcia,et al.  The status and characteristics of the goat (Capra hircus) and its potential role as a significant milk producer in the tropics: A review , 1997 .

[14]  F. Fluharty,et al.  Effects of dietary energy intake and protein concentration on performance and visceral organ mass in lambs. , 1997, Journal of animal science.

[15]  M. Razzaque,et al.  FEEDLOT GROWTH AND EFFICIENCY OF THREE-WAY CROSS LAMBS AS AFFECTED BY GENOTYPE, AGE AND DIET , 1996 .

[16]  M. Gibb,et al.  Performance of British Saanen, Boer × British Saanen and Anglo-Nubian castrated male kids from 8 weeks to slaughter at 28, 33 or 38 kg live weight , 1993 .

[17]  A. H. Kirton,et al.  Carcass and meat quality attributes of commercial goats in New Zealand , 1992 .

[18]  M. Shahjalal,et al.  The effect of changes in dietary protein and energy on growth, body composition and mohair fibre characteristics of British Angora goats , 1992 .

[19]  F. Ruvuna,et al.  Effects of breed and castration on slaughter weight and carcass composition of goats , 1992 .

[20]  P. V. Soest,et al.  Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. , 1991, Journal of dairy science.

[21]  C. Lu,et al.  Feed intake and weight gain of growing goats fed diets of various energy and protein levels. , 1990, Journal of animal science.

[22]  E. Dransfield,et al.  Carcass and eating quality of ram, castrated ram and ewe lambs , 1990 .

[23]  I. Kadim,et al.  Carcass characteristics of Southdown rams from high and low backfat selection lines , 1989 .

[24]  B. Mcgregor.  Effects of different nutritional regimens on the productivity of Australian cashmere goats and the partitioning of nutrients between cashmere and hair growth , 1988 .

[25]  J. M. Forbes.  6 – Dietary factors affecting intake , 1986 .

[26]  H. R. Cross,et al.  Utilization of the Intact Male for Red Meat Production: A Review , 1982 .

[27]  S. Jindal,et al.  Influence of Dietary Energy on the Body Composition and Food Conversion Efficiency During Growth in Goats , 1980 .

[28]  J. Hancock,et al.  Effects of castration on growth rate, feed conversion efficiency and carcass quality in Damascus goats , 1977 .

[29]  R. M. Koch,et al.  Carcass Composition, Quality and Palatability Attributes of Bulls and Steers Fed Different Energy Levels and Killed at Four Ages1 ,2 , 1977 .

[30]  M. Pay,et al.  Growth, food conversion and carcass characteristics in castrated and entire male pigs fed three different dietary protein levels , 1973, The Journal of Agricultural Science.

[31]  S. Singh,et al.  Studies on goats: I. Effect of plane of nutrition on the reproductive performance of does , 1973, The Journal of Agricultural Science.

[32]  R. Field,et al.  Effect of castration on meat quality and quantity. , 1971, Journal of animal science.

[33]  G. Bradford,et al.  Effects of castrating lambs on growth and body composition. , 1964 .