Interactive effects among porcine somatotropin, the beta-adrenergic agonist salbutamol, and dietary lysine on growth performance and nitrogen balance of finishing swine2

Abstract

An experiment was conducted to evaluate the interactive effects among porcine somatotropin (pST), salbutamol, and dietary lysine on growth performance, nitrogen balance, and carcass characteristics of finishing barrows (n = 32; 62.8 kg initially). Two replicate 32-d studies were set up in a split-plot design to evaluate singular and combined use of pST (0 or 4 mg/d) and salbutamol (0 or 2.75 ppm of the diet) as whole-plot treatments and diets containing .8, 1.2, 1.6, or 2.0% lysine as subplot treatments. Dietary lysine levels were administered within subplots in a 4 x 4 Latin square with pigs allowed 4 d of adjustment to diets followed by 4 d of urine and feces collection for determination of N retention and apparent digestibility of DM and N. Interactions between lysine and salbutamol were not found (P > .16). A pST x lysine interaction (P < .05) resulted in ADG being maximized at 1.2% lysine for pST-treated pigs (lysine quadratic, P < .02) but decreased linearly (P < .02) with increasing lysine for pigs receiving buffer. Pigs injected with 4 mg/d of pST had improved gain:feed (G:F) up to 1.2% lysine (lysine quadratic, P < .05), but no further increase to 2% lysine, whereas pigs injected with buffer showed no benefit from increased lysine (pST x lysine, P < .06). Pigs receiving buffer had greater increases in plasma urea N (PUN) as lysine increased than those receiving pST (pST x lysine, P < .002), but PUN was reduced by pST (P < .001) regardless of lysine level.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of zilpaterol hydrochloride on growth performance, carcass characteristics, and wholesale cut yield of hair-breed ewe lambs consuming feedlot diets under moderate environmental conditions

“…Therefore, that hypothesis suggests a reduction in weight of noncarcass components in ZH ewe lambs as a consequence of an increase in carcass muscle mass. However, Montgomery et al (2009) raised this hypotli-csis based on results from pigs (Hansen et al, 1994) and mice (Sharma et al, 1997), where liver and kidney weight decreased significantly by oral administration of clembuterol and salbutamol. However, no effect of ZH was observed on visceral organs in this study.…”

Interrelationships between dietary lysine, sex, and porcine somatotropin administration on growth performance and protein deposition in pigs between 80 and 120 kg live weight.

“…Although the effects of lysine on protein deposition were relatively small, which may have hindered curve fitting, there was sufficient evidence for these authors to conclude that the lysine requirement for pST-treated pigs was approximately 10 to 12 g/kg. Hansen et al (1994) conducted a nitrogen balance study in pigs over the live weight range of 63 to 99 kg and concluded that the lysine requirement of pigs injected with 4 mg pST/d was 12 g/kg. A difficulty with interpretation of this study was that the levels of dietary lysine were in 4 g/kg increments between 8 and 20 g/kg, making it hard to interpolate between 8 and 12 g lysine/kg.…”

Níveis de lisina para leitoas selecionadas geneticamente para deposição de carne magra, dos 60 aos 95 kg

“…leitoas com alta capacidade de deposição de carne magra na carcaça, dos 50 aos 80 kg. Por outro lado, considerando os dados de consumo de lisina diário, os resultados obtidos neste estudo estão coerentes com os obtidos por diversos autores (CROMWELL et al, 1993;OWEN et al, 1994;HANSEN et al, 1994;SUSENBETH et al, 1994;e HAHN et al, 1995), que variaram de 22 a 25,5 g/dia, para suínos em terminação.…”