Multitrial analysis of the effects of copper level and source on performance in nursery pigs

A multitrial analysis was conducted to evaluate the effect of different levels of Cu from either Cu(2-hydroxy-4-(methylthio)butanoic acid [HMTBa])2 or CuSO4 on growth performance in nursery pigs. Six nursery trials were conducted from 2007 to 2012 under the same commercial conditions with initial BW of 5.75 ± 0.41 kg at 21 ± 3 d of age; the trials lasted for 42 d with a 3-phase feeding program (7 d in Phase I, 14 d in Phase II, and 21 d in Phase III). Diets were medicated with antibiotics and supplemented with 3,000 mg/kg Zn as ZnO during phases I and/or II. Treatments included a basal diet without added Cu or according to the NRC (1998) and supplemental levels of Cu (50 to 250 mg Cu/kg diet) from either Cu(HMTBa)2 or CuSO4; HMTBa was supplemented to make diets isomethionine. Treatments from each trial included 6 or 9 replicate pens/treatment with 22 to 25 piglets/pen. Mixed model analysis was conducted in which trial was considered a random effect, Cu level was considered a continuous fixed effect, and Cu source was a fixed effect. The basal diet within trial and statistical tests of the intercept between sources were not different, resulting in fitting a common intercept mixed model to the overall responses across phases. Cumulative ADG and ADFI quadratically responded (P < 0.05) with increasing Cu supplementation; predicted optimal ADG and ADFI occurred at 174 and 119 mg/kg, respectively. Increasing Cu supplementation linearly improved G:F (P = 0.054). No differences between sources were observed in ADG or ADFI. Numerically, pigs fed Cu(HMTBa)2 had higher ADG and lower ADFI compared to pigs fed CuSO4, resulting in better G:F for pigs supplemented with Cu(HMTBa)2 compared to pigs supplemented with CuSO4 (P < 0.01). The linear slope for increasing Cu supplementation on G:F was 2.1-fold higher for Cu(HMTBa)2 than that of CuSO4, with larger differences occurring in Phase II. In conclusion, Cu supplementation in nursery diets resulted in improved performance and Cu(HMTBa)2 is more effective than CuSO4 in improving feed efficiency.

Detection of batch effects in liquid chromatography-mass spectrometry metabolomic data using guided principal component analysis

Metabolomics based on liquid chromatography-mass spectrometry (LC-MS) is a powerful tool for studying dynamic responses of biological systems to different physiological or pathological conditions. Differences in the instrumental response within and between batches introduce unwanted and uncontrolled data variation that should be removed to extract useful information. This work exploits a recently developed method for the identification of batch effects in high throughput genomic data based on the calculation of a δ statistic through principal component analysis (PCA) and guided PCA. Its applicability to LC-MS metabolomic data was tested on two real examples. The first example involved the repeated analysis of 42 plasma samples and 6 blanks in three independent batches, and the second data set involved the analysis of 101 plasma and 18 blank samples in a single batch with a total runtime of 50h. The first and second data set were used to evaluate between and within-batch effects using the δ statistic, respectively. Results obtained showed the usefulness of using the δ statistic together with other approaches such as summary statistics of peak intensity distributions, PCA scores plots or the monitoring of IS peak intensities, to detect and identify instrumental instabilities in LC-MS.

Fracturas del extremo distal de la falange proximal

Las fracturas del extremo distal de la falange proximal, localizadas en la cabeza o cuello de la misma, son con frecuencia inestables y por su complejidad, suelen ser fracturas difíciles de tratar correctamente. No es por ello infrecuente que se produzcan complicaciones tales como consolidaciones en mala posición, seudoartrosis, artrosis postraumática o rigideces de los dedos afectados. El conocimiento de los distintos patrones de fractura, así como su diagnóstico y tratamiento adecuados, son esenciales para conseguir los mejores resultados posibles.

Exponemos en este artículo nuestra experiencia con este tipo de lesiones, realizando una revisión de la literatura de las mismas, tanto en niños como en adultos, analizando los diferentes tipos de fracturas, los tratamientos posibles, las complicaciones más frecuentes que hemos observado y nuestras recomendaciones para evitarlas y tratarlas.

Effects of the rate of insulin infusion during isoglycemic, hyperinsulinemic clamp procedures on measures of insulin action in healthy, mature thoroughbred mares

The objective of this study was to determine whether the rate of insulin infusion during isoglycemic hyperinsulinemic clamp procedures affected measures of insulin action, including glucose disposal and plasma non-esterified fatty acid, endothelin-1, and nitric oxide concentrations, in mature, healthy horses. Eight thoroughbred mares were studied during a 2-h hyperinsulinemic clamp procedure, conducted at each of 4 rates of insulin infusion: 0 (CON), 1.2 (LOWINS), 3 (MEDINS), and 6 (HIGHINS) mU · kg(-1) · min(-1). The infusion rate of a dextrose solution was adjusted throughout the clamp procedures to maintain blood glucose levels within 10% of baseline glucose concentrations. Plasma insulin concentrations were measured throughout the clamp procedures, and used with the rate of glucose infusion to calculate the plasma insulin concentration-to-rate of glucose infusion ratio, a measure of insulin action on glucose disposal. The rate of glucose infusion increased with rate of insulin infusion (P < 0.05). The plasma insulin concentration-to-rate of glucose infusion ratio was highest for the LOWINS treatment (P < 0.05) and decreased by 62% (P < 0.05) and 84% (P < 0.05) for the MEDINS and HIGHINS treatments, respectively. Although plasma non-esterified fatty acid concentrations were lower than baseline by t = 30 min of the clamp procedures in the LOWINS, MEDINS, and HIGHINS treatments (P < 0.05), the decline was similar for all 3 rates of insulin infusion. Jugular vein plasma nitric oxide and endothelin-1 concentrations were not affected by insulin infusion rate (P > 0.05). The data indicate that it is important to standardize insulin infusion rate if data are to be compared between hyperinsulinemic clamp studies.

Insulin infusion stimulates whole-body protein synthesis and activates the upstream and downstream effectors of mechanistic target of rapamycin signaling in the gluteus medius muscle of mature horses

Little is known about the role insulin plays in regulating whole-body and muscle protein metabolism in horses. The objective of this study was to determine the effects of graded rates of insulin infusion on plasma amino acid concentrations and the activation of factors in the mechanistic target of rapamycin signaling pathway in the skeletal muscle of horses. Isoglycemic, hyperinsulinemic clamp procedures were conducted in 8 mature, thoroughbred mares receiving 4 rates of insulin infusion: 0 mU · kg(-1) · min(-1) (CON), 1.2 mU · kg(-1) · min(-1) (LOWINS), 3 mU · kg(-1) · min(-1) (MEDINS), and 6 mU · kg(-1) · min(-1) (HIGHINS). Blood samples were taken throughout the clamp procedures to measure plasma amino acid concentrations, and a biopsy from the gluteus medius muscle was collected at the end of the 2-h clamp to measure phosphorylation of protein kinase B, eukaryotic initiation factor 4E-binding protein 1, and riboprotein S6. Plasma concentrations of most of the essential amino acids decreased (P < 0.05) after 120 min of insulin infusion in horses receiving the LOWINS, MEDINS, and HIGHINS treatments, with the largest decreases occurring in horses receiving the MEDINS and HIGHINS treatments. Phosphorylation of protein kinase B, 4E-binding protein 1, and riboprotein S6 increased with all 3 rates of insulin infusion (P > 0.05), relative to CON, with maximum phosphorylation achieved with MEDINS and HIGHINS treatments. These results indicate that insulin stimulates whole-body and muscle protein synthesis in mature horses.

Effects of jugular-infused lysine, methionine, and branched-chain amino acids on milk protein synthesis in high-producing dairy cows

In addition to lysine and methionine, current ration-balancing programs suggest that branched-chain amino acid (BCAA) supply may also be limiting in dairy cows. The objective of this study was to investigate whether BCAA, leucine, isoleucine, and valine become limiting for milk protein synthesis when methionine and lysine supply were not limiting. Nine multiparous Holstein cows with an average milk production of 53.5±7.1 kg/d were randomly assigned to 7-d continuous jugular infusions of saline (CTL), methionine and lysine (ML; 12 g and 21 g/d, respectively), or ML plus leucine, isoleucine, and valine (ML+BCAA; 35 g, 15 g, and 15 g/d, respectively) in a 3×3 Latin square design with 3 infusion periods separated by 7-d noninfusion periods. The basal diet consisted of 40% corn silage, 14% alfalfa hay, and a concentrate mix, and respectively supplied lysine, methionine, isoleucine, leucine, and valine as 6.1, 1.8, 4.7, 8.9, and 5.3% of metabolizable protein. Dry matter intake (23.9 kg/d), milk yield (52.8 kg/d), fat content (2.55%), fat yield (1.33 kg/d), lactose content (4.77%), lactose yield (2.51 kg/d), and milk protein efficiency (0.38) were similar across treatments. Protein yield and protein content were not significantly different between ML (1.52 kg/d and 2.88%, respectively) and ML+BCAA (1.51 kg/d and 2.83%, respectively), but they were significantly greater than that of CTL (1.39 kg/d and 2.71%). Cows that received ML+BCAA had less milk urea nitrogen content (10.9 mg/dL) compared with milk of CTL cows (12.4 mg/dL) and ML cows (11.8 mg/dL). Whereas high-producing cows responded positively to methionine and lysine supplementation, no apparent benefits of BCAA supplementation in milk protein synthesis were found. Infusion of BCAA may have stimulated synthesis of other body proteins, probably muscle proteins, as evidenced by decreased milk urea nitrogen.

Regulation of protein synthesis in mammary glands of lactating dairy cows by starch and amino acids

The objective of this study was to evaluate local molecular adaptations proposed to regulate protein synthesis in the mammary glands. It was hypothesized that AA and energy-yielding substrates independently regulate AA metabolism and protein synthesis in mammary glands by a combination of systemic and local mechanisms. Six primiparous mid-lactation Holstein cows with ruminal cannulas were randomly assigned to 4 treatment sequences in a replicated incomplete 4 x 4 Latin square design experiment. Treatments were abomasal infusions of casein and starch in a 2 x 2 factorial arrangement. All animals received the same basal diet (17.6% crude protein and 6.61 MJ of net energy for lactation/kg of DM) throughout the study. Cows were restricted to 70% of ad libitum intake and abomasally infused for 36 h with water, casein (0.86 kg/d), starch (2 kg/d), or a combination (2 kg/d starch+0.86 kg/d casein) using peristaltic pumps. Milk yields and composition were assessed throughout the study. Arterial and venous plasma samples were collected every 20 min during the last 8h of infusion to assess mammary uptake. Mammary biopsy samples were collected at the end of each infusion and assessed for the phosphorylation state of selected intracellular signaling molecules that regulate protein synthesis. Animals infused with casein had increased arterial concentrations of AA, increased mammary extraction of AA from plasma, either no change or a trend for reduced mammary AA clearance rates, and no change in milk protein yield. Animals infused with starch had increased milk and milk protein yields, increased mammary plasma flow, reduced arterial concentrations of AA, and increased mammary clearance rates and net uptake of some AA. Infusions of starch increased plasma concentrations of glucose, insulin, and insulin-like growth factor-I. Starch infusions increased phosphorylation of ribosomal protein S6 and endothelial nitric oxide synthase, consistent with changes in milk protein yields and plasma flow, respectively. Phosphorylation of the mammalian target of rapamycin was increased in response to starch only when casein was also infused. Thus, cell signaling molecules involved in the regulation of protein synthesis differentially responded to these nutritional stimuli. The hypothesized independent effects of casein and starch on animal metabolism and cell signaling were not observed, presumably because of the lack of a milk protein response to infused casein.

Use of Saccharomyces cerevisiae fermentation product on growth performance and microbiota of weaned pigs during Salmonella infection

Anaerobically fermented yeast products are a rich source of nutritional metabolites, mannanoligosaccharides, and β-glucans that may optimize gut health and immunity, which can translate into better growth performance and a reduced risk of foodborne pathogens. The objective of this study was to quantify the effects of Saccharomyces cerevisiae fermentation product (Diamond V Original XPC) inclusion in nursery diets on pig performance and gastrointestinal microbial ecology before, during, and after an oral challenge with Salmonella. Pigs (n = 40) were weaned at 21 d of age, blocked by BW, and assigned in a 2 × 2 factorial arrangement consisting of diet (control or 0.2% XPC) and inoculation (sterile broth or Salmonella). Pigs were fed a 3-phase nursery diet (0 to 7 d, 7 to 21 d, and 21 to 35 d) with ad libitum access to water and feed. On d 14, pigs were orally inoculated with 10(9) cfu of Salmonella enterica serovar Typhimurium DT104 or sterile broth. During d 17 to 20, all pigs were treated with a 5 mg/kg of BW intramuscular injection of ceftiofur-HCl. Growth performance and alterations in the gastrointestinal microbial ecology were measured during preinoculation (PRE; 0 to 14 d), sick (SCK; 14 to 21 d), and postinoculation (POST; 21 to 35 d). Body weight and ADG were measured weekly. Rectal temperature (RT) was measured weekly during PRE and POST, and every 12 h during SCK. Diet had no effect on BW, ADG, or RT during any period (P = 0.12 to 0.95). Inclusion of XPC tended (P < 0.10) to increase Salmonella shedding in feces during SCK. Consumption of XPC altered the composition of the gastrointestinal microbial community, resulting in increased (P < 0.05) populations of Bacteroidetes and Lactobacillus after Salmonella infection. Pigs inoculated with Salmonella had decreased ADG and BW, and increased RT during SCK (P < 0.001). Furthermore, fecal Salmonella cfu (log(10)) was modestly correlated (P = 0.002) with BW (r = -0.22), ADFI (r = -0.27), ADG (r = -0.36), G:F (r = -0.18), and RT (r = 0.52) during SCK. After antibiotic administration, all Salmonella-infected pigs stopped shedding. During POST, an interaction between diet and inoculation (P = 0.009) on ADG indicated that pigs infected with Salmonella grew better when eating XPC than the control diet. The addition of XPC to the diets of weanling pigs resulted in greater compensatory BW gains after infection with Salmonella than in pigs fed conventional nursery diets. This increase in BW gain is likely associated with an increase in beneficial bacteria within the gastrointestinal tract.

Ordered transcriptional factor recruitment and epigenetic regulation of tnf-alpha in necrotizing acute pancreatitis

Tauhe expression of the critical initiator cytokine TNF-alpha was strongly upregulated in vivo in acute necrotic pancreatitis (AP) in rodents and in vitro in TNF-alpha activated acinar AR42J cells. Upregulation of tnf-alpha, inos, icam-1 and il-6 occurred both in TNF-alpha receptor 1 and 2 knock-out mice, but not in TNF-alpha knock-out mice, in cerulein-induced acute pancreatitis. Chromatin immunoprecipitation analysis showed that transcriptional factors (ELK-1, SP1, NF-kappaB and EGR-1) and chromatin modification complexes (HDAC1, HDAC2, GCN5, PCAF and CBP) were recruited and/or released from the promoter in a strictly ordered mechanism. Activation of tnf-alpha gene was also accompanied by an ordered increased level of histone H3K9, H3K14 and H3K18-acetylation and H3K4 methylation, as well as H4K5 acetylation. A better knowledge of the molecular mechanisms that control tnf-alpha gene regulation will provide deeper understanding of the initiation and development of the inflammatory processes occurring in acute pancreatitis triggered by TNF-alpha cytokine.