EurekaMag
+ Most Popular
Cunninghamia lanceolata plantations in China
Mammalian lairs in paleo ecological studies and palynology
Studies on technological possibilities in utilization of anhydrous milk fat for production of recombined butter-like products
Should right-sided fibroelastomas be operated upon?
Large esophageal lipoma
Apoptosis in the mammalian thymus during normal histogenesis and under various in vitro and in vivo experimental conditions
Poissons characoides nouveaux ou non signales de l'Ilha do Bananal, Bresil
Desensitizing efficacy of Colgate Sensitive Maximum Strength and Fresh Mint Sensodyne dentifrices
Administration of fluid by subcutaneous infusion: revival of a forgotten method
Tundra mosquito control - an impossible dream?
Schizophrenia for primary care providers: how to contribute to the care of a vulnerable patient population
Geochemical pattern analysis; method of describing the Southeastern limestone regional aquifer system
Incidence of low birth weights in a hospital of Mexico City
Tabanidae
Graded management intensity of grassland systems for enhancing floristic diversity
Microbiology and biochemistry of cheese and fermented milk
The ember tetra: a new pygmy characid tetra from the Rio das Mortes, Brazil, Hyphessobrycon amandae sp. n. (Pisces, Characoidei)
Risk factors of contrast-induced nephropathy in patients after coronary artery intervention
Renovation of onsite domestic wastewater in a poorly drained soil
Observations of the propagation velocity and formation mechanism of burst fractures caused by gunshot
Systolic blood pressure in a population of infants in the first year of life: the Brompton study
Haematological studies in rats fed with metanil yellow
Studies on pasteurellosis. I. A new species of Pasteurella encountered in chronic fowl cholera
Dormancy breaking and germination of Acacia salicina Lindl. seeds
therapy of lupus nephritis. a two-year prospective study

Effects of a "step-up" ractopamine feeding program, sex, and social rank on growth performance, hoof lesions, and Enterobacteriaceae shedding in finishing pigs


Effects of a "step-up" ractopamine feeding program, sex, and social rank on growth performance, hoof lesions, and Enterobacteriaceae shedding in finishing pigs



Journal of Animal Science 87(1): 304-313



ISSN/ISBN: 0021-8812

PMID: 18765847

DOI: 10.2527/jas.2008-1188

Increasing concern for animal well-being and food safety has stimulated the investigation of feed additives such as ractopamine (RAC), a beta-agonist widely used to improve production performance of finishing pigs. The objective of this study was to determine effects of RAC feeding, delivered as a "step-up" program (5 mg/kg for 2 wk followed by 10 mg/kg for 2 wk), on growth performance, Enterobacteriaceae shedding, including Salmonella, and hoof lesions, also taking into account sex and social rank of pigs. A total of 64 barrows and gilts (balanced by treatment and sex) were assigned to pens of 4 (by sex) as either control (CTL) or RAC treatment. Social ranks (dominant, intermediate, and subordinate) of pigs in each pen were determined by behavioral observation during 48 h post-mixing. Fecal samples were collected once per week for 5 wk. At slaughter, the 32 dominant and subordinate barrows and gilts (16/sex) were examined for hoof lesions, and luminal contents from ileum, cecum, and rectum were collected. Pigs fed RAC had increased growth performance (P < 0.05) with social rank of animals affecting overall ADG (P < 0.05). Gilts gained more backfat than barrows when comparing to baseline values at both 10th and last ribs (P < 0.05), whereas loin eye area increased at a similar rate for both barrows and gilts (P > 0.10). No significant effect of RAC feeding was found on backfat or loin eye area (P > 0.10). At slaughter, RAC-fed pigs had greater BW (P < 0.05). Despite the positive effects of RAC feeding on growth performance, pigs fed the compound had a greater frequency of front and rear hoof lesions as did barrows and dominant individuals (P < 0.05). Detectable concentrations of Salmonella shedding were not identified at any time during the experiment. Enterobacteriaceae shedding concentrations from RAC-fed pigs peaked at the first week of feeding and progressively decreased until slaughter. At slaughter, rectal and cecal Enterobacteriaceae concentrations were less in RAC-fed pigs than in CTL pigs (P < 0.05). Social rank tended to affect gut Enterobacteriaceae populations of barrows more than in gilts (P < 0.10). The effects of RAC feeding on hoof soundness and Enterobacteriaceae populations in the gastrointestinal tract of finishing pigs warrant further investigation. It is also proposed that the integration of the social rank status of the individual into future studies should be considered, because it may affect treatment responses.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 052852912

Download citation: RISBibTeXText

Related references

The effects of a step-up ractopamine feeding program on growth performance and low-sodium ham characteristics of purebred Berkshire pigs. Journal of Animal Science 91(11): 5535-5543, 2013

Effect of a ractopamine feeding program on growth performance and carcass composition in finishing pigs. Journal of Animal Science 82(8): 2474-2480, 2004

A step-up ractopamine feeding program for finishing pigs. Revista Colombiana de Ciencias Pecuarias 31(4): 276-284, 2018

Behavior and peripheral amine concentrations in relation to ractopamine feeding, sex, and social rank of finishing pigs. Journal of Animal Science 88(3): 1184-1194, 2010

Effects of Feeding a Finisher Feed Containing Ractopamine HCl to Pigs Sorted By Body Weight at Placement on Growing-Finishing Pig Growth Performance. Journal of Animal Science 96: 186-187, 2018

Effects of Feeding a Finisher Feed Containing Ractopamine HCl to Pigs Sorted By Body Weight at Placement on Growing-Finishing Pig Growth Performance. Journal of Animal Science 96: 186-187, 2018

Effects of ractopamine plus amino acids on growth performance, carcass characteristics, meat quality, and ractopamine residues of finishing pigs. Ciencia E Investigacion Agraria 41(3): 297-308, 2014

The effect of ractopamine dose and duration of feeding on growth performance and carcass characteristics of finishing pigs. Journal of Dairy Science 85(Suppl. 1): 219, 2002

Effect of zilpaterol and ractopamine feeding program on growth performance and carcass characteristics of finishing lambs. Journal of Dairy Science 93: 171-172, 2010

Effects of ractopamine level and feeding duration on the performance and carcass characteristics of late finishing market pigs. Journal of Dairy Science 90: 444, 2007

Effects of ractopamine level and feeding duration on the performance and carcass characteristics of late finishing market pigs. Poultry Science 86: 444-444, 2007

Effects of ractopamine HCl on growth performance and within-pen weight variation in finishing pigs. Journal of Swine Health and Production 13(6): 318-321, 2005

The effect of dietary ractopamine concentration and duration of feeding on growth performance, carcass characteristics, and meat quality of finishing pigs. Journal of Animal Science 82(11): 3245-3253, 2004

Interactive effects of dietary ractopamine HCl and L-carnitine on finishing pigs: I. Growth performance. Journal of Animal Science 91(7): 3265-3271, 2013

Time-response relationship of ractopamine feeding on growth performance, plasma urea nitrogen concentration, and carcass traits of finishing pigs. Journal of Animal Science 91(2): 811-818, 2013