Stress susceptibility in pigs supplemented with ractopamine.

Ractopamine is a ß-adrenergic agonist used as an energy repartitioning agent in the diets of finishing pigs. Most ractopamine studies are limited to evaluations of growth performance and meat quality, and there is little information on the effects of this additive on the behavior and welfare of pigs. Therefore, the objective of this study was to evaluate various indicators of stress caused by feeding diets containing ractopamine. One hundred seventy barrows and 170 gilts weighing 107.3 kg were allocated to 30 pens with 10 to 12 barrows or gilts per pen. Pigs were offered 1 of the 3 dietary treatments (0, 5, or 10 mg ractopamine/kg) for 28 d with 5 barrow pens and 5 gilt pens per treatment. Pigs were evaluated for behavior 3 d per week 1 wk before the initiation of the experiment and throughout the experiment. Each pig was classified into 1 of the 13 activities (drinking water, lying alone, lying in clusters, standing, nosing pig, sitting, feeding, biting pig, walking, exploring, running away, playing, and mounting pen mates) and also grouped into 1 of the 3 categories (calm, moving, and feeding themselves) based on those activities. At the end of the experiment, 3 pigs from each pen were slaughtered, and blood samples were collected during exsanguination to determine physiological indicators of stress (cortisol, lactate, and creatine-kinase enzymes). The incidence of skin and carcass lesions was determined at shoulder, loin, and ham. Ractopamine had no effect (P > 0.05) on pig behavior, total number of skin and carcass lesions, or blood concentrations of cortisol or lactate. However, there was an increase (P < 0.05) of creatine kinase concentrations in pigs receiving ractopamine-supplemented feed. This finding is consistent with the concept that ractopamine may cause muscular disorders, and this warrants further investigation.

Meat quality of swine supplemented with ractopamine under commercial conditions in Brazil.

Commercial crossbred barrows and gilts (n = 340) were used to study the effects of different dietary inclusions of ractopamine hydrochloride (RAC) on quality of LM and semimembranosus muscle (SM). Pigs were blocked by BW (107.3 ± 0.76 kg) and allotted to gender-specific pens (10 to 12 pigs/pen), and within blocks, pens of barrows or gilts (10 pens/treatment) were randomly assigned to 1 of 3 dietary RAC inclusions (0, 5, or 10 mg/kg) fed during the last 28 d before slaughter. Initial (45-min) and ultimate (24-h) pH and temperature were measured in LM and SM. Visual and instrumental [lightness (L*), redness (a*), and yellowness (b*) values] color as well as drip loss percentages were measured in both muscles after the 24-h chilling period at 1 to 4 °C. The LM was also evaluated for marbling, and samples of the LM were used to measure intramuscular fat (IMF) content, cooking losses, and Warner-Bratzler shear force (WBSF). Pork quality characteristics of the LM (P ≥ 0.227) and SM (P ≥ 0.082) did not differ between barrows and gilts. Furthermore, neither pH nor temperature of the LM (P ≥ 0.164) or SM (P ≥ 0.284) was affected by feeding pigs RAC. The LM from pigs fed 10 mg/kg of RAC received lesser (P = 0.032) subjective color scores than LM from pigs fed 0 and 5 mg/kg of RAC, and LM from pigs fed 10 mg/kg of RAC was less (P = 0.037) red than LM from pigs fed 0 mg/kg of RAC. In addition, SM from pigs fed 10 mg/kg of RAC had lesser (P ≤ 0.015) a* and b* values than pork from control-fed pigs; however, L* values for LM and SM were not (P ≥ 0.081) affected by dietary RAC. Drip loss percentages of the LM were similar (P = 0.815) among RAC treatments, but the SM from RAC-fed pigs had smaller (P = 0.020) drip loss percentages than SM from pigs fed 0 mg/kg of RAC. Marbling scores and IMF content of the LM did not (P ≥ 0.133) differ among RAC treatments; however, WBSF values were greater (P = 0.005) for LM chops from pigs fed 10 mg/kg than chops from pigs fed 0 and 5 mg/kg of RAC. Even though feeding barrows and gilts 10 mg/kg of dietary RAC reduced (P = 0.050) cooking losses of LM chops compared with feeding 5 mg/kg of RAC, including 10 mg/kg of RAC in the diet of finishing pigs reduced pork tenderness. Therefore, results from this study support the recommendation that including 5 mg/kg of RAC in finishing diets should improve live pig performance without detrimental effects on fresh pork quality and cooked pork palatability.

Lithiasis in 1,313 kidney transplants: incidence, diagnosis, and management.

BACKGROUND: Renal transplantation remains the optimal treatment of patients with end-stage renal disease. Urinary lithiasis represents an unusual urologic complication in renal transplantation, with an incidence of <1%. Today, recipients of kidneys from deceased donors are more likely to receive grafts with undiagnosed lithiasis, which does not occur in patients from living donors, owing to screening with computerized tomography. OBJECTIVE: The aim of this study was to evaluate the incidence, diagnosis, and therapeutic management of renal lithiasis in transplanted kidneys at a single institution. METHODS: We reviewed the medical records for 1,313 patients who underwent kidney transplantation from February 1968 to February 2011. RESULTS: Among the grafts, 17 patients (1.29%) had nephrolithiasis: 9 women and 8 men. Ages ranged from 32 to 63 years (mean = 45.6 years). Fifteen patients received kidneys from cadaveric and only 2 from living related donors. Two stones, both located inside the ureter, were identified during transplant surgery (11.7%). Three instances of lithiasis were incidentally diagnosed by ultrasound during graft evaluation, within 7 days after surgery (17.6%); all 3 were in the calyces. The 12 remaining patients had the stones diagnosed later (70.58%): 6 in the calyces, 3 in the renal pelvis, and 3 inside the ureter. CONCLUSIONS: Urinary lithiasis is a rare complication in renal transplantation. In most patients the condition occurs without pain. The diagnosis and treatment options for graft urolithiasis are similar to those patients with nephrolithiasis in the general population. Extracorporeal shock wave lithotripsy (ESWL) was the most common treatment method.

Effect of organic acids and mannanoligosaccharide on excretion of Salmonella typhimurium in experimentally infected growing pigs.

The effect of organic acids and mannanoligosaccharide addition to the diet was assessed in pigs orally inoculated with Salmonella typhimurium. Forty-six growers were distributed among four treatments: Basal Diet (BD); BD+encapsulated organic acids; BD+free organic acids; BD+mannanoligosaccharide. Seroconversion was monitored, and feces and tissue samples were tested for Salmonella isolation. No treatment prevented the carrier state, but a tendency of lower fecal excretion was observed in the group treated with mannanoligosaccharide.

Concentraçäo mínima inibitória de óxido de zinco para amostras de Escherichia coli isoladas de suínos com diarréia pós-desmama / Minimal inhibitory concentration of zinc oxide to Escherichia coli strains isolated from swine with post-weaning diarrhea

Avaliou-se a açäo inibitória in vitro do óxido de zinco (ZnO) para 29 amostras de Escherichia coli isoladas de diarréia pós-desmame dos suínos. Avaliaram-se também associaçöes entre sulfato de cobre (CuSO4), sulfato ferroso (FeSO4) e ZnO para verificar se os elementos cobre e ferro interferiram com a açäo do ZnO. A concentraçäo mínima inibitória (CMI) do ZnO para as amostras de E. coli variou de 120 ug/ml a 280 ug/ml. Treze amostras foram inibidas por 200 ug/ml, seis amostras foram inibidas por 220 ug/ml e uma amostra por 280 ug/ml. As CMI do CuSO4 e FeSO4 foram: 1024 ug/ml (CuSO4: uma amostra, FeSO4: cinco amostras) e 2048 g/ml (CuSO4: 19 amostras, FeSO4: 15 amostras). Quando se associaram 128 ug/ml e 256 ug/ml de CuSO4 a diferentes concentraçöes de ZnO (100 a 300 ug/ml), os valores da CMI do ZnO foram menores. Semelhantemente, os valores da CMI do FeSO4 foram menores quando se associaram CuSO4 (128 ug/ml) e ZnO (100 ug/ml) a diferentes concentraçöes de FeSO4 (256 a 2048 ug/ml). Os resultados mostraram que a tolerância das amostras de E. coli para ZnO é variável e que a associaçäo de ZnO, CuSO4 e FeSO4 nas concentraçöes testadas causou efeito inibitório aditivo sobre as amostras