Theo van Kempen

Starch with High Amylose Content and Low In Vitro Digestibility Increases Intestinal Nutrient Flow and Microbial Fermentation and Selectively Promotes Bifidobacteria in Pigs

Diets containing different starch types can affect enzymatic digestion of starch and thereby starch availability for microbial fermentation in the gut. However, the role of starch chemistry in nutrient digestion and flow and microbial profile has been poorly explained. Eight ileal-cannulated pigs (29.4 ± 0.9 kg body weight) were fed 4 diets containing 70% purified starch (amylose content, <5, 20, 28, and 63%; reflected by in vitro maximal digestion rate; 1.06, 0.73, 0.38, and 0.22%/min, respectively) in a replicated 4 × 4 Latin square. Ileal and fecal starch output, postileal crude protein yield, fecal total SCFA and total butyrate content, and gene copies of Bifidobacterium spp. in feces were higher (P < 0.05) when pigs consumed the slowly digestible starch diet than the remaining 3 starch diets. The in vitro starch digestion rate had a negative, nonlinear relationship with ileal starch flow (R(2) = 0.98; P < 0.001). Ileal starch flow was positively related to Bifidobacterium spp. (R(2) = 0.27; P < 0.01), Lactobacillus group (R(2) = 0.22; P < 0.01), and total butyrate content (R(2) = 0.46; P < 0.01) but was not related to Enterobacteriaceae (R(2) < 0.00; P = 0.92). In conclusion, starch with high amylose content and low in vitro digestibility increased postileal nutrient flow and microbial fermentation and selectively promoted Bifidobacterium spp. in the distal gut.

Starch with High Amylose and Low in Vitro Digestibility Increases Short-Chain Fatty Acid Absorption, Reduces Peak Insulin Secretion, and Modulates Incretin Secretion in Pigs

Diets containing different starch types affect peripheral glucose and insulin responses. However, the role of starch chemistry in kinetics of nutrient absorption and insulin and incretin secretion is poorly understood. Four portal vein-catheterized pigs (35.0 ± 0.2 kg body weight) consumed 4 diets containing 70% purified starch [0-63.2% amylose content and 0.22 (slowly) to 1.06%/min (rapidly) maximum rate of in vitro digestion] for 7-d periods in a 4 × 4 Latin square. On d 7, blood was collected for 12 h postprandial with simultaneous blood flow measurement for determining the net portal appearance (NPA) of nutrients and hormones. The NPA of glucose, insulin, C-peptide, and glucose-dependent insulinotropic polypeptide (GIP) during 0-4 h postprandial were lower (P < 0.05) and those of butyrate and total SCFA were higher (P < 0.05) when pigs consumed the diet containing slowly digestible compared with rapidly digestible starch. The peak NPA of insulin occurred prior to that of glucose when pigs consumed diets containing rapidly digestible starch. The kinetics of insulin secretion had a linear positive relation with kinetics of NPA of glucose (R(2) = 0.50; P < 0.01). In conclusion, starch with high amylose and low in vitro digestibility decreases the kinetics of glucose absorption and insulin and GIP secretion and increases SCFA absorption and glucagon-like peptide-1 secretion. In conclusion, starch with high amylose content and a lower rate and extent of in vitro digestion decreased glucose absorption and insulin secretion and increased SCFA absorption.

Infrared technology in animal production

Infrared (IR) spectroscopy is based on the principle that the chemical bonds in organic molecules absorb or emit infrared light when their vibrational state changes. In the near IR part of the spec...Infrared (IR) spectroscopy is based on the principle that the chemical bonds in organic molecules absorb or emit infrared light when their vibrational state changes. In the near IR part of the spectrum, large changes in vibrational state are observed (overtones), while in the mid IR region, primary vibrations are produced. The latter yields sharper, more clearly defined peaks that are better suited for quantitative purposes. Raman spectroscopy, in which the decay of the vibration is observed after strong excitation of the sample, is a variant on mid IR spectroscopy. A major challenge in applying IR spectroscopy to animal production is sample presentation. Transmission is the most powerful method well suited to liquids and gases but is inappropriate for undiluted solids. Although reflection offers an alternative for solids, it is less than ideal for quantitative purposes as the path length is not known. For pastes and opaque liquids, attenuated total reflectance offers good possibilities for the future as it acts like a transmission device but sample application is simple. A novel method is photo-acoustics in which the heating of a sample (as it absorbs the IR light) is measured using a microphone. IR spectroscopy is typically fast and easy to use. In feedmills it allows the quality (e.g. proximate and nutritionally relevant parameters such as metabolisable energy) of feed ingredients and complete feeds to be monitored. In meat processing IR spectroscopy offers the opportunity to assess meat and fat quality, and perhaps even palatability (texture and flavour). New developments in IR spectroscopy will expand its applications further. These include hand-held instruments that may find use in determining digestive disorders among birds in the field, fibreoptics that will allow instantaneous measurements to be made in almost any part of a plant, tunable lasers (with their much stronger signals) that will make IR spectroscopy much more powerful, and imaging IR spectroscopy which may be used to determine the homogeneity of meat (e.g. colour). IR spectroscopy, with its speed, ease of use and versatility, could be about to become one of the most powerful analytical techniques available to the animal production industries. It promises to allow for improved quality control in virtually every aspect of production, from feed manufacture to final product evaluation.

High Amylose Starch with Low In Vitro Digestibility Stimulates Hindgut Fermentation and Has a Bifidogenic Effect in Weaned Pigs

BACKGROUND Dietary amylose resists enzymatic digestion, thereby providing a substrate for microbial fermentation that stimulates proliferation of beneficial microbiota and production of short-chain fatty acids (SCFAs) in the large intestine of pigs and humans. However, the effect of increasing dietary amylose in pigs immediately postweaning on growth, nutrient digestibility and flow, and intestinal microbial and SCFA profiles has not been studied and can be used as a model for newly weaned human infants. OBJECTIVE We studied the effects of increasing dietary amylose on growth, nutrient digestibility, and intestinal microbial and metabolite profiles in weaned pigs. METHODS Weaned pigs (n = 32) were randomly allocated to 1 of 4 diets containing 67% starch with 0%, 20%, 28%, or 63% amylose for 21 d. Subsequently, pigs were killed to collect feces and digesta for measuring starch digestion and microbial and metabolite profiles. RESULTS Feeding weaned pigs 63% compared with 0%, 20%, and 28% amylose decreased (P < 0.05) feed intake by 5% and growth by ≥ 12%. Ileal digestibility of dry matter decreased (P < 0.05) by 10% and starch by 9%, thereby increasing (P < 0.05) hindgut fermentation, cecal and colonic total SCFAs, and colonic Bacteroides, and lowering (P < 0.01) ileal, cecal, and colonic pH in pigs consuming 63% compared with 0%, 20%, and 28% amylose. Cecal and colonic Bifidobacteria spp. increased by 14-30% (P < 0.05) and Clostridium clusters IV and XIVa were decreased (P < 0.01) in pigs consuming 63% compared with 0%, 20%, and 28% amylose. CONCLUSION Increasing dietary amylose in pigs immediately postweaning stimulated hindgut fermentation and Bifidobacteria spp., thereby manipulating the gut environment, but also reduced intake and growth. An optimum dietary amylose concentration should be determined, which would maintain desired growth rate and gut environment in weaned pigs.

Hypophosphatemia as a key factor in sudden infant death syndrome (SIDS)

Dear Sir, Sudden Infant Death Syndrome or SIDS remains an important cause of mortality in infants. The 2011 publication of Siren and Siren (1) and the subsequent letter to the editor (2) focus on critical diaphragm failure as a possible cause and provide plausible evidence. However, these articles do not explore the metabolic basis for this critical diaphragm failure. Several authors, including Aubier et al. (3) and Fiaccadori et al. (4) have described that the diaphragm is extremely susceptible to hypophosphatemia, and this may be the origin of the symptoms reported by Siren and Siren. Hence, it may well be the yet unexplored underlying mechanism responsible for SIDS. A reason for suspecting hypophosphatemia as the cause for SIDS is because neonates are extremely prone to developing hypophosphatemia as shown in numerous publications (e.g. (5-8)). A very brief period of stress, like separation from the mother or a brief period of illness, can result in phosphaturia severe enough to result in the loss of 50% of the free phosphate pool within 24 hours. This results in an immediate drop in blood phosphate levels. Worse, this hypophosphatemia can subsequently become aggravated over the course of 1–2 weeks without obvious visible symptoms and despite resumption of normal eating behavior, something not reported in older subjects. In infants with risk factors for SIDS like intrauterine growth retardation, exposure to cigarette smoke, male sex, and heat stress, this phosphaturetic stress response is enhanced possibly through augmented or longer-lasting sympathetic activity (9,10), and, hence, they are more prone to develop severe hypophosphatemia and ATP deficiency. Hypophosphatemia not only affects contraction of the diaphragm, but it is also involved in the formation of 2,3-diphosphoglycerate (2,3-DPG; more correctly referred to as 2,3-bisphosphoglycerate) in erythrocytes. This 2,3-DPG regulates the release of oxygen from hemoglobin. Tissues with a high metabolic activity result in high levels of 2,3-DPG in the blood causing the liberation of oxygen (11-13). Hypophosphatemia impedes the formation of 2,3-DPG, which subsequently prevents the release of oxygen from hemoglobin and, in effect, suffocates the tissue. Thus, severe hypophosphatemia results in signs of asphyxiation despite adequate access to free air (14), either through inducing an ATP deficiency affecting the diaphragm or through inhibiting oxygen release from hemoglobin. For example, in briefly stressed subjects, in parallel with the drop in plasma phosphate, a doubling of the ratio of pCO2/pO2, an increase in SpO2, and lactic acidosis were observed but without obvious visible signs of distress. If severe enough, this could lead to death from inner suffocation (SIDS). The presence of fetal hemoglobin may also play a role in SIDS. Fetal hemoglobin purportedly has a higher binding affinity for oxygen (15) and thus could predispose an infant to SIDS when 2,3-DPG is compromised. Other symptoms of SIDS can also be explained by hypophosphatemia. Hypophosphatemia can lead to petechiae: minor hemorrhages caused by platelet dysfunction (16,17) and often seen postmortem in SIDS victims. Similarly, pulmonary edema (18) has been linked to hypophosphatemia, as have cardiac arrhythmias (19,20). Hypophosphatemia is also implicated in the morbidity and mortality associated with refeeding syndrome (21) and in hypophosphatemic rickets, which is more prevalent in boys (22) in line with a higher incidence of SIDS in boys. Siren and Sirens (1) comment that REM sleep inhibits intercostal muscles compounded by diurnal rhythms in blood phosphate could explain why SIDS strikes during night-time REM sleep. Also, phosphate has a seasonal rhythm with lows in the winter which could explain a higher prevalence of SIDS in this season, and 2,3-DPG is lower in infants exposed to cigarette smoke which could explain a higher incidence of SIDS in houses of smokers (23,24). In summary, both the etiology as well as the symptoms of SIDS can be explained by hypophosphatemia. A brief stressor can induce hypophosphatemia in infants, particularly in those with SIDS risk factors, and aggravate it despite resumption of normal food intake. This since the urinary loss of phosphate induced by stress or a large drop in metabolic rate and the subsequent enhanced phosphate demand for re-started anabolic processes cannot be quickly compensated by normal dietary intake. This hypophosphatemia can aggravate to the point of affecting O2 release from red blood cells through a depletion of 2,3-DPG or affect diaphragm contractility through ATP deficiency, either one which leads to death from apparent suffocation: SIDS.

Pigs as recyclers for nutrients contained in Bermuda grass harvested from spray fields.

The ability of pigs to use nitrogen and energy in Bermuda grass was evaluated in order to assess whether Bermuda grass harvested from spray fields could be fed to pigs as a means to recycle nitrogen. Digestibility of Bermuda grass incorporated into corn-soybean meal diets was evaluated in heavy finishing pigs and gestating sows. Results suggest that Bermuda grass digestibility is negative in animals not adapted to a high-fiber diet. Enzymes improve this digestibility, but even with enzymes, nitrogen digestibility was poor. Pigs fed a diet containing 10% Bermuda grass required a one week adaptation period for maximal digestion; following adaptation, pigs can digest approximately 40% of the energy in Bermuda grass but none of the nitrogen. Feeding Bermuda grass to pigs as a means of recycling nitrogen is thus not recommended.

Unraveling the cause of white striping in broilers using metabolomics

ABSTRACT White striping (WS) is a major problem affecting the broiler industry. Fillets affected by this myopathy present pathologies that compromise the quality of the meat, and most importantly, make the fillets more prone to rejection by the consumer. The exact etiology is still unknown, which is why a metabolomics analysis was performed on breast samples of broilers. The overall objective was to identify biological pathways involved in the pathogenesis of WS. The analysis was performed on a total of 51 muscle samples and distinction was made between normal (n = 19), moderately affected (n = 24) and severely affected (n = 8) breast fillets. Samples were analyzed using gas chromatographic mass spectral analysis and liquid chromatography quadrupole time-of-flight mass spectrometry. Data were subsequently standardized, normalized and analyzed using various multivariate statistical procedures. Metabolomics allowed for the identification of several pathways that were altered in white striped breast fillets. The tricarboxylic acid cycle exhibited opposing directionalities. This is described in literature as the backflux and enables the TCA cycle to produce high-energy phosphates through matrix-level phosphorylation and, therefore, produce energy under conditions of hypoxia. Mitochondrial fatty acid oxidation was limited due to disturbances in especially cis-5–14:1 carnitine (log2 FC of 2, P < 0.01). Because of this, accumulation of harmful fatty acids took place, especially long-chain ones, which damages cell structures. Conversion of arginine to citrulline increased presumably to produce nitric oxide, which enhances blood flow under conditions of hypoxia. Nitric oxide however also increases oxidative damage. Increases in taurine (log2 FC of 1.2, P < 0.05) suggests stabilization of the sarcolemma under hypoxic conditions. Lastly, organic osmolytes (sorbitol, taurine, and alanine) increased (P < 0.05) in severely affected birds; likely this disrupts cell volume maintenance. Based on the results of this study, hypoxia was the most likely cause/initiator of WS in broilers. We speculate that birds suffering from WS have a vascular support system in muscle that is borderline adequate to support growth, but triggers like activity results in local hypoxia that damages tissue.

Water-soluble all-rac α-tocopheryl-phosphate and fat-soluble all-rac α-tocopheryl-acetate are comparable vitamin E sources for swine

Vitamin E, as all-rac α-tocopheryl-acetate (TAc), has a bioavailability of only 5.4% in swine and, therefore, is a poor vitamin E source. Tocopheryl-phosphate (TP) has been used successfully as a vitamin E source around 1940 but it was subsequently replaced by TAc as it was easier to manufacture. Recently, it has been proposed as an in vivo intermediate in vitamin E metabolism with possibly gene-regulatory functions. TP may be more bioavailable than TAc as intestinal hydrolysis and emulsification are not required. The objective of this work was to compare the bioavailability of TAc and TP in swine. Piglets (18.6 ± 0.6 kg) fitted with jugular catheters received a single test meal (350 g) containing either deuterated (trimethyl-d9) TAc or TP (75 IU/kg body weight, n = 8 per treatment). Twelve serial blood samples were obtained starting premeal until 78 h postmeal for analysis of deuterated T and TP using LC MS/MS. Results were standardized by dividing them by the dose per kg body weight and were subsequently modeled with a multicompartment model. T from TAc had a slow appearance rate (0.040 ± 0.014 h-1) and rapid disappearance rate (0.438 ± 0.160 h-1) with a plateau value of 0.414 ± 0.129 µM/(µmol/kg BW). TP appeared faster in plasma (0.119 ± 0.058 h-1, P = 0.01) while the elimination rate was similar (0.396 ± 0.098 h-1, P = 0.51). The plateau value of TP was only numerically higher (0.758 ± 0.778 µM/(µmol/kg BW), P = 0.34). TP was quickly converted to T; its appearance rate was 0.026 ± 0.009 h-1, slower than the appearance rate of T from TAc (P = 0.01), whereas the elimination rate was 0.220 ± 0.062 h-1, slower than that of T from TAc (P = 0.00). The conversion of TP to T may have been incomplete, as its plateau value was only 0.315 ± 0.109 µM/(µmol/kg BW). The area under the curve, expressed relative to area under the curve for T from TAc, was 34.5% for TP and 107.3% for T from TP. These data confirm that TP is more quickly absorbed than T from TAc. TP is also converted to T and thus a functional precursor of T. Nevertheless, as a source of T, TP failed to offer a clear advantage over TAc in bioavailability.

The Course of Parturition Affects Piglet Condition at Birth and Survival and Growth through the Nursery Phase

Simple Summary In this study, data were collected on the condition in which piglets were born, and this was related to their position in the birth order, and to the progress of parturition. The objective of the study was to find out if these observations were related to performance in early life, up to 10 weeks. It appeared that the later the piglets were born in a litter, the higher the risk of being stillborn, and this was aggravated in sows that took a relatively long time to give birth to their litter. In the first few piglets in a litter, risk of stillbirth was only 2%, whereas this increased to 17% in piglets born 13th in the litter or later. Similarly, birth order affected the condition of the liveborn piglets, with blood values such as pH being evident of suboptimal oxygenation in piglets born later. These blood values were predictive of neonatal behaviour such as colostrum intake, but also for neonatal survival and growth during suckling and even to 10 weeks of life. These data are the first in piglets to emphasise the impact of condition at birth on survival and growth until the end of the nursery phase. Abstract The aim of this study was to relate the course of parturition to the condition of piglets at birth, based on umbilical cord blood acid-base values, and relate the condition at birth to neonatal survival and performance up to 10 weeks of life. Data were collected from 37 spontaneous unassisted parturitions, and neonatal performance was based on observations of 516 piglets. Stillbirth rate increased from 2% in the first piglets, to 17% in piglets born 13th in the litter or later. This was aggravated in sows with longer than average stage II of parturition. Umbilical cord blood values also reflected the effect of birth order, with pH decreasing and lactate increasing in the course of parturition. Interestingly, sows that had a long expulsion stage of parturition also took longer to give birth to the first four piglets (r = 0.74), suggesting that sows with complicated parturition were already experiencing problems at the start of expulsion of piglets. Piglets with signs of asphyxia, based on umbilical blood lactate higher than 4.46 mmol/L, were slower to start suckling, had a higher risk of neonatal mortality, and had a slower growth rate over the first 10 weeks of life.