Effects of dietary supplementation with L-arginine on the endogenous losses of amino acids in growing pigs exposed to heat stress.

Exposing pigs to heat stress (HS) provokes higher death of intestinal cells, resulting in elevated endogenous intestinal losses (EIL) of amino acids (AA) and damage to intestinal epithelia. Arginine (Arg) is precursor for the synthesis of polyamines, which are involved in proliferation of intestinal cells and restoration of the intestinal epithelia. Thus the effect of adding L-Arg to diets for HS pigs on the EIL of AA was analyzed. Twelve pigs (23.1 ± 1.1 kg body weight) implanted with T-type cannulas at the end of ileum were individually housed and allowed 15-days for surgery recovery under thermoneutral (TN) conditions (22 ± 2 °C). Following, the pigs were randomly assigned to one of three treatments: TN pigs fed a semi-purified, corn starch-3% casein basal diet (TN-B); HS pigs with the basal diet (HS-B); HS pigs consuming the basal diet supplemented with 0.20% L-Arg (HS-Arg). The experiment consisted of two 9-day periods; each period included 7-days of adaptation to their respective diet, followed by a 2-day ileal digesta collection period. Digesta was collected during 12 consecutive hours each day. The pigs were fed twice a-day. Ambient temperature (AT) inside the TN and HS rooms ranged from 18.6 to 27.6 °C and from 29.5 to 40.7 °C, respectively. Body temperature followed a pattern similar to that of AT. The daily EIL of indispensable AA increased (P < 0.01) in the HS-B pigs compared to both the TN-B and the HS-Arg pigs, however, there was no EIL difference between the TN-B and the HS-Arg pigs (P > 0.05). Likewise, with the exception of serine, daily losses of endogenous dispensable AA in the HS-B pigs were higher (P < 0.01) in comparison with those of TN-B and HS-Arg pigs. In summary, HS exposure compared to TN conditions increases the loss of endogenous AA, but dietary supplementation with L-Arg helped to counteract the negative HS effect.

Effect of heat stress on performance and expression of selected amino acid and glucose transporters, HSP90, leptin and ghrelin in growing pigs.

Exposing animals to high ambient temperature provokes heat stress (HS) that may affect cellular function and reduced productive performance. The effect of chronic exposure (21d) of pigs to high ambient temperature on expression of amino acid (b(0,+)AT, CAT1) and glucose (SGLT1, GLUT4) transporters, ghrelin, leptin and HSP90 was evaluated. Eighteen pigs (32.6kg body weight) were distributed into 3 groups: (1) pigs housed under natural high ambient temperature conditions, and fed ad libitum (HS); (2) pigs housed in an air-conditioned room at 24°C (thermo-neutral) fed ad libitum (TNad); (3) pigs housed as in (2), but pair-fed with the HS pigs (TNpf). Body temperature, respiratory frequency, weight gain, feed intake, and feed conversion ratio were measured. At d-21 pigs were euthanized and samples from stomach, duodenum, jejunum, liver, longissimus and semitendinosus muscles, and white adipose tissue were collected for mRNA analysis. In the HS room ambient temperature fluctuated every day (23.6-37.6°C). Respiratory frequency and body temperature were higher in HS pigs (P<0.001). Weight gain and feed intake of TNad were higher (P<0.001) than TNpf and HS; gain: feed ratio was not affected by ambient temperature. Expression of HSP90 was higher in duodenum and longissimus (P≤0.038) of HS compared to TNpf. Expression of ghrelin, leptin and b(0,+)AT were not affected by ambient temperature (P>0.050). CAT1 expression in liver was higher (P=0.050) but in longissimus was lower (P=0.017) in HS than in TNpf pigs. Expression of SGLT1 was higher (P=0.045) in duodenum of HS than in TNpf but it was not different in jejunum (P=0.545); GLUT4 tended to be higher in liver and semitendinosus of HS pigs (P=0.063). In conclusion, feed intake remains low whereas respiratory frequency and body temperature remain higher; and expression of HSP90, CAT1, SGLT1 and GLUT4 increases in some tissues in pigs under chronic HS conditions.

A Capsaicin-Based Phytogenic Solution Improves Performance and Thermal Tolerance of Heat-Stressed Growing Pigs.

Exposure to heat stress (HS) detrimentally affects pig performance. This study explored whether a dietary phytogenic solution based on Capsicum spp. (PHY) could enhance the thermal tolerance of heat-stressed growing pigs. Forty-two individually housed pigs were randomly assigned to three treatments: thermoneutral pigs on a control diet (TN-C) and pigs subjected to HS fed the control diet either without (HS-C) or with supplemental PHY (HS-PHY). The TN-C group exhibited increased average daily gain (ADG) and feed intake (FI) compared to both HS-C (p < 0.01) and HS-PHY pigs (p < 0.05) and better feed efficiency compared to HS-C pigs only (p < 0.01). However, the HS-PHY pigs showed significantly higher FI (p < 0.01) and ADG (p < 0.05) compared to HS-C pigs. HS pigs displayed higher body temperatures (BTs) than TN pigs (p < 0.01), yet HS-PHY pigs experienced a lesser increase in BT compared to HS-C pigs (p < 0.05). Supplementation with PHY mitigated some effects of HS, increasing serum superoxide dismutase and catalase activity, reducing HSP90 expression in longissimus dorsi muscle, and elevating jejunal villus height compared to HS-C pigs (p < 0.05), reaching levels akin to TN-C pigs. Additionally, PHY supplementation resulted in lower serum urea levels than HS-C pigs (p < 0.01) and similar myosin gene expression to TN-C pigs (p > 0.1), suggesting enhanced amino acid post-absorptive utilization for lean tissue growth. In conclusion, dietary PHY supplementation partially offset the adverse effects of HS on pig performance by improving thermal tolerance.

Effect of dl-methionine supplementation above requirement on performance; intestinal morphology, antioxidant activity, and gene expression; and serum concentration of amino acids in heat stressed pigs.

The intestinal morphology and function can be compromised in pigs exposed to heat stress (HS), partly due to increased production of reactive-oxygen species. Because methionine (Met) functions as intracellular antioxidant, the requirement of Met may be increased in HS-pigs. The effect of dietary supplementation with dl-Met above requirement on performance, small intestine morphology, antioxidant enzymes activity, amino acid transporters expression, and serum concentration (SC) of free AA in HS-pigs was evaluated. A basal wheat-soybean meal diet was formulated to meet 100% Met requirement with the other indispensable AA exceeding at least 20% their requirement. Sixty individually housed pigs (23.0 ± 2.4 kg BW, 12 pigs per treatment) were randomly assigned to five treatments: TN100, thermal-neutral (22.7 °C) housed pigs fed the basal diet; HS100, HS120, HS140, HS160; HS-pigs (29.6 °C to 39.4 °C) fed the basal diet supplemented with dl-Met to contain 0%, 20%, 40%, and 60% dl-Met above the requirement, respectively. Pigs had free access to feed and water during the 21-d trial. Blood samples were collected on day 18 to analyze the absorptive AA-SC. The effect of ambient temperature (HS100 vs. TN100), as well as the linear and quadratic effects of increasing Met levels in the diets for HS-pigs were analyzed. The HS100 pigs gained less weight than TN100 and HS120 pigs (P < 0.01); gain:feed was also higher in HS120 pigs than in HS100 pigs (P ≤ 0.05). Feed intake of TN100 pigs was higher than that of HS-pigs fed the dl-Met supplemented diets (P < 0.05). Villi height reduced in pigs HS, but Met supplementation quadratically increased it (P < 0.05). Superoxide dismutase and catalase activities, reduced glutathione concentration, and relative expression of B0AT2 in ileum decreased (P < 0.05), but glutathione peroxidase activity increased in HS-pigs. dl-Met supplementation linearly affected catalase and glutathione peroxidase activities, as well as the relative expression of b0,+AT in jejunum (P < 0.05) of HS-pigs. The SC of Ile, Leu, Lys, Phe, and Val were higher in HS100 pigs than in TN100 pigs (P < 0.05). Graded levels of supplemental dl-Met in diets for HS-pigs linearly decreased SC of Ile, Leu, and Val (P < 0.05), tended to decrease His, Lys, and Thr (P < 0.10), and increased Met (P < 0.01). In conclusion, HS had negative effect on weight gain and intestinal morpho-physiology; however, it was ameliorated by adding 20% Met above the requirement in diets for growing pigs.

The exposure of pigs to ambient temperature above their comfort zone affects several functions of the small intestine, especially those related with digestion of feed and absorption of nutrients, which in turn reduces the availability of nutrients for growth. Amino acids such as methionine are involved in multiple functions of intestinal cells. Thus, methionine supplementation may help pigs to overcome the negative impact of their exposure to high ambient temperature. Indeed, methionine supplementation to the diet increased growth rate and feed efficiency of pigs housed under heat stress, which was presumably associated with an improvement in the utilization of the absorbed amino acids.

Effect of arginine supplementation on the morphology and function of intestinal epithelia and serum concentrations of amino acids in pigs exposed to heat stress.

The exposure of pigs to heat stress (HS) appears to damage their intestinal epithelia, affecting the absorption of amino acids (AAs). Arg is involved in the restoration of intestinal epithelial cells but HS reduces Arg intake. The effect of dietary supplementation with Arg on the morphology of intestinal epithelia, AA transporter gene expression, and serum concentration (SC) of free AAs in HS pigs was analyzed. Twenty pigs (25.3 ± 2.4 kg body weight) were randomly assigned to two dietary treatments: Control (0.81% Arg), wheat-soybean meal diet supplemented with l-Lys, l-Thr, dl-Met, and l-Trp, and the experimental diet where 0.16% free l-Arg was supplemented to a similar Control diet (+Arg). All pigs were individually housed and exposed to HS, fed ad libitum with full access to water. The ambient temperature (AT), recorded at 15-min intervals during the 21-d trial, ranged on average from 29.6 to 39.4 °C within the same day. Blood samples were collected on day 18 at 1600 hours (AT peak); serum was separated by centrifugation. At the end of the trial, five pigs per treatment were sacrificed to collect samples of mucosa scratched from each small intestine segment. The expression of AA transporters in intestinal mucosa and the SC of AAs were analyzed. Villi height (VH) was higher (P < 0.01) in the duodenum, jejunum, and ileum but the crypt depth did not differ between the Control and the +Arg pigs. Supplementation of l-Arg increased the mRNA coding for the synthesis of the cationic AA transporter b0,+ (P < 0.01) and the neutral AA transporter B0 (P < 0.05) in the duodenum by approximately 5-fold and 3-fold, respectively, but no effect on mRNA abundance was observed in the jejunum and ileum. The supplementation of l-Arg increased serum Arg, His, Met, Thr, Trp, and urea (P < 0.05) and also tended to increase Val (P < 0.10) but did not affect Ile, Lys, Leu, and Phe. These results indicate that supplementing 0.16% l-Arg to the Control diet may help to improve the function of the small intestine epithelium, by increasing the VH, the abundance of AA transporters, and the SC of most indispensable AAs in pigs exposed to HS conditions. However, the lack of effect of supplemental Arg on both Lys SC and weight gain of pigs suggests that increasing the Lys content in the +Arg diet might be needed to improve the performance of HS pigs.

Extra dietary protein-bound or free amino acids differently affect the serum concentrations of free amino acids in heat-stressed pigs1.

Pigs exposed to heat stress (HS) reduce feed intake and consequently the consumption of AA. Adding extra protein-bound or free AA to the diet may correct the reduced AA intake of HS pigs. However, extra protein-bound AA may further increase the body heat load, whereas extra free AA does not affect the heat load of HS pigs. Two experiments were conducted. In Exp. 1, the performance depression because of HS, compared with thermal neutrality, was determined with 30 pigs (31.1 ± 1.2 kg BW) fed diets with AA only as protein or as a mix of protein and free AA. Heat stress pigs consumed 18 to 25% less Lys and Thr than thermal neutral. In Exp. 2, the effect of extra dietary protein-bound or free AA on performance and serum concentration of AA in 25 HS pigs (33.6 ± 0.65 kg BW) was evaluated. Treatments were as follows: CON, wheat-soybean meal-free Lys-Thr-Met diet; xP diet, 26% more protein than the CON diet; xAA diet, 24% or more of each AA than the recommended level. Pigs were fed ad libitum. Blood samples were collected between 1600 and 1700 h, when pigs were exposed to the highest ambient temperature (around 41.3 °C). Body temperature ranged daily from 39.9 to 41.1 °C. The performance data were reported already. Pigs fed the xP diet consumed more of all indispensable AA and dispensable AA than the CON pigs (P < 0.05), and more Arg, Ile, Asp, Glu, Gly, and Ser (P < 0.05) than the xAA pigs. Except for Arg, xAA pigs consumed more indispensable AA than the CON pigs (P < 0.05). Serum Arg, His, Lys, Phe, Thr, Trp, and Val, was higher (P < 0.05) in xP than in CON pigs. Except for Ile serum, indispensable AA were higher in xAA than in CON pigs (P < 0.05). Serum Ile, Leu, Thr, and Val were higher (P < 0.05), and Met tended to be higher (P < 0.10) in xAA than in xP pigs. The difference of Ile, Leu, Met, Thr, and Val between the CON and the xAA pigs was larger than that between the CON and the xP pigs (P < 0.05). Serum Asn and Tyr were higher, and Cys and Glu were lower (P < 0.05) in xP than in CON pigs. Serum Cys tended to be lower in xAA than in CON pigs (P < 0.10). Asp and Glu were higher (P < 0.05) in xAA pigs than in xP pigs. In conclusion, these serum AA results combined with the reported performance data indicate that extra free AA in diets for HS pigs may help to correct the reduced AA availability and performance of HS pigs, although higher levels of specific AA such as Ile and Met might be needed.

Eficacia la técnica del arrastre en la extracción de monedas del esófago en los pacientes atendidos en la Unidad de Emergencia de INSN, en el año 2012-2013 / Effectiveness of the drag technique in the extraction of coins of the esophagus in patients attended in the Emergency Unit at the INSN in the period August 2012-March 2013

Determinar la eficacia de la técnica del arrastre en la extracción de monedas del esófago; en los pacientes atendidos en el servicio de emergencia del INSN, en el periodo Agosto 2012-Marzo 2013. Material y métodos: Estudio descriptivo, prospectivo en niños de 1 a 15 años de edad, que ingirieron monedas, y fueron atendidos en el servicio de emergencia del INSN, en el periodo Agosto 2012-Marzo 2013. Los pacientes fueron de ambos sexos, que habían ingerido monedas, con un tiempo de evolución no mayor de 48 horas. Se realizó el análisis estadístico descriptivo de los datos, utilizando el programa SPSS v.15 para el procesamiento de datos. Resultados: Se estudiaron 134 niños con cuerpo extraño en vía digestiva (moneda) entre los meses de agosto del 2012, a marzo del 2013. De ello se extrajeron 105 monedas mediante la técnica del arrastre, sin ninguna complicación. Los cuerpos extraños fueron extraídos en un primer intento 93 monedas del esófago (88.57 por ciento), en dos intentos 10 monedas (9.52 por ciento) y en tres intentos 02 monedas (1.9 por ciento). A seis pacientes (5.71 por ciento) no se les pudo extraer la moneda por la técnica de arrastre. Conclusión: La técnica del arrastre con sonda Foley es una técnica efectiva en un 94.5 por ciento, inocua y que baja los costos en la extracción de monedas del esófago en niños que acuden a la emergencia del hospital del niño...

Pólipo inflamatorio del intestino en el niño / Intestinal inflammatory polyp in child

Se estudian 15 casos de lesiones únicas del colon y recto, que se definen en la literatura como pólipos inflamatorios, pólipos juveniles, seudopólipos, etc, con las caracteristicas histológicas en las que se entremezclan los elementos de tipo glandular con dilatación quística, células inflamatorias y un estroma de tejido conectivo variado, así como reacción ósea vista por nosotros en dos de los casos. Estos pólipos inflamatorios, generalmente son lesiones únicas, raras veces recidivan y por los conceptos vertidos no tienen carácter maligno. Suelen encontrarse alrededor de los 6 ó 7 años de edad y el síntoma predominante es el sangramiento rectal. Ellos deben diferenciarse de otras formas de pólipos que pueden traer un carácter maligno. En cuanto al mecanismo patogénico, no existe una teoría convincente para este tipo de lesión, aunque nosotros nos acercamos al planteamiento hipotético hecho por Klepinger(AU)