Higher Metabolizable Energy Research Articles

Consistent ozone-induced decreases in pasture forage quality across several grassland types and consequences for UK lamb production

In this study we have demonstrated that rising background ozone has the potential to reduce grassland forage quality and explored the implications for livestock production. We analysed pasture samples from seven ozone exposure experiments comprising mesotrophic, calcareous, haymeadow and sanddune unimproved grasslands conducted in open-top chambers, solardomes and a field release system. Across all grassland types, there were significant increases in acid detergent fibre, crude fibre and lignin content with increasing ozone concentration, resulting in decreased pasture quality in terms of the metabolisable energy content of the vegetation. We derived a dose-response function for metabolisable energy of the grassland with ozone concentration, applicable to a range of grassland types, and used this to predict effects on pasture quality of UK vegetation at 1km resolution using modelled ozone data for 2007 and for predicted higher average ozone concentrations in 2020. This showed a potential total reduction in lamb production in the UK of approximately 4% in 2020 compared to 2007. The largest impacts were in geographical areas of modest ozone increases between the two years, but where large numbers of lambs were present. For an individual farmer working to a very small cost margin this could represent a large reduction in profit, both in regions where the impacts per lamb and those where the impacts per km2 of grazing land are largest. In the short term farmers could adapt their lamb management in response to changed forage quality by additional supplementary feed of high metabolisable energy content. Nationally this increase in annual additional feed in 2020 compared to 2007 would be 2,166 tonnes (an increase of 0.7%). Of added concern are the longer-term consequences of continual deterioration of pasture quality and the implications for changes in farming practices to compensate for potential reductions in livestock production capacity.

Value of spray-dried egg in pig nursery diets

High-quality protein ingredients have been used in nursery diets, in spite of expensive ingredients, to minimize nutritional deficiency and disease problems. Recent dramatic increases in prices of protein products for nursery diets have exacerbated the challenge. Spray-dried egg may be a part of the solutions. Therefore, this review describes the value of spray-dried egg in nursery diets as a high-quality protein source. Spray-dried egg is egg by-product and is produced by only eggs without shell that are below the USDA Grade B standards. Spray-dried egg is an excellent nutrient source: 1) highly digestible, 2) excellent balance of amino acids, 3) rich content of fat, and 4) high metabolizable energy. These can be attributed to growth of nursery pigs. Beyond the provision of bioavailable nutrients, spray-dried egg also may provide specific physiological benefits. Spray-dried egg contains 1) immunoglobulin antibodies (IgY: IgG in egg yolk) that may attach to intestinal pathogens and excrete them and 2) lysozymes antimicrobial protein that can damage bacteria cell wall. Thereby feeding spray-dried egg may reduce concentration of intestinal pathogen and thus improve potential gut health or enteric disease resistance in nursery pigs. This is important for physiologically immature weaned pigs. Based on these benefits, spray-dried egg is believed to have the same benefits as spray-dried plasma protein and milk products in diets for nursery pigs. Therefore, it is suggested that spray-dried egg has a great potential as a valuable protein source in nursery diets.

Effect of different combinations of soybean-maize silage on its chemical composition, nutrient intake, degradability, and performance of Pelibuey lambs.

Sheep raising in the state of Guerrero, México, is a primary activity that is worth about US$3,251,931 annually. The objective of the present study was to evaluate the chemical composition, degradability, nutrient intake, and animal performance of Pelibuey lambs fed on different combinations of maize-soybean silages. Twenty-one combinations of maize silage (MS) and soybean silage (SS) were evaluated at day 45 post-ensiling; in each combination, MS was replaced by 5% of SS. The 21 combinations were analysed for crude protein (CP) and chemical composition. In order to obtain a statistical criterion of potential treatments for the animal feeding test, a cluster analysis was performed based on the CP contents of all combinations at day 45 post-ensiling. From cluster analysis, four treatments were selected T1 = 100-0% (MS/SS), T8 = 65-35%, T12 = 45-55%, and T16 = 25-75%. Results indicated that cluster analysis was useful for identifying the potential treatments for animal feeding based on the crude protein content. The dry matter (DM), organic matter (OM), and acid detergent lignin (ADL) contents did not declined significantly (P > 0.05) during the fermentation of silages but CP content decreased from day 0 to 45 post-ensiling. The treatment with the highest estimated microbial crude protein synthesis was T8 and it showed the highest metabolizable energy intake, high feed efficiency with a forage-concentrate ratio of 84:16.

Soybean oil and beef tallow in dry extruded diets for adult dogs

The aim of the study was to determine the effects of two different fat sources (soybean oil (SO) and beef tallow (BT)) in dry extruded dog diets on the intake of food and metabolizable energy (ME), on faecal characteristics and apparent total tract digestibility (ATTD) of nutrients and energy. Ten adult dogs of different breeds were used in a Latin square design. Five experimental diets were designed from a basal diet. A Control diet was coated with 1% SO and four other diets were obtained by coating the basal diet with 6.5% and 13% of SO or BT. The Control, 6.5% and 13% coated diets contained approximately 8.5%, 15% and 20% fat, respectively. The dogs had similar dry matter (DM) intakes and, consequently, higher ME intakes with an increased fat content for both sources (p < 0.05). Fat digestibility was highest for Diet SO13% (p < 0.05). The ATTD of DM and organic matter was highest (p < 0.05) for Diets SO13% and BT13%. Fat coating improved the faecal score, especially for Diet BT13%. The dietary ratios of protein:fat:carbohydrate [% of ME] were close to AAFCO’s estimates. For SO a higher ATTD (99.1%) and ME content (38.88 MJ/kg) was estimated than for BT (ATTD 92.9% and 36.37 MJ ME/kg). Both SO and BT can comprise up to 13% of the diet. However, SO was more susceptible to leaking from the kibbles with the coating method applied.

Interactive effects of fenugreek (Trigonella foenum-graecum L.) seed extract supplementation and dietary metabolisable energy levels on the growth performance, total tract digestibility, blood profiles, and excreta gas emission in broiler chickens

The present experiment was conducted to evaluate the effect of fenugreek seed extract (FSE) supplementation of broiler diets containing two levels of metabolisable energy (ME) on the growth performance, nutrient retention, blood profile, and excreta gas emission. A total of 816, day-old broilers (Ross 308) were allotted to four treatments, with 12 replications and 17 broilers per replication for 28 days. Experimental treatments consisted of a 2 × 2 factorial design with two dietary energy levels [high ME or low ME (high ME – 100 kcal less], and two levels of supplemental FSE (0% or 0.1%). The results showed that broilers fed with high ME or 0.1% FSE diet during 1–14 days showed improvement in bodyweight gain, compared with low ME or no FSE treatment, respectively (P &lt; 0.05). Total tract digestibility of dry matter and nitrogen of broilers fed with 0.1% FSE were observed to be higher than that with no FSE treatments (P &lt; 0.05). The interaction between ME level and FSE supplementation for total- and low-density lipoprotein-cholesterol was indicated by a significant decrease in total- and low-density lipoprotein-cholesterol when FSE was added in a higher ME diet (P ≤ 0.05). Excreta ammonia gas emission in low ME or 0.1% FSE treatment was found to be lower than in high ME or no FSE treatments, respectively (P &lt; 0.05). These results show that adding FSE at a level of 0.1% in diet can improve the early weight gain, total tract digestibility, and decrease excreta ammonia gas emission of broilers. In addition, reduction in total- and low-density lipoprotein-cholesterol was observed to be more effective by the supplementation of 0.1% FSE in high ME groups.

Effect of species on chemical composition, metabolisable energy, organic matter digestibility and methane production of oak nuts

The aim of the current experiment was to determine the effect of species on chemical composition metabolisable energy (ME), organic matter digestibility (OMD) and methane production of oak nuts. The crude protein content was ranged from 2.71% to 6.14%. Crude protein of oak nuts from Quercus ithaburensis ssp. macrolepis was significantly higher than those of the other oak species. Neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of oak nuts were ranged from 19.29% to 34.58% and 12.65% to 20.85%, respectively. NDF and ADF contents of oak nuts from Quercus coccifera were significantly higher than those of the other oak species. The NFC contents of Quercus suber and Q. ithaburensis ssp. macrolepis were significantly higher than those of Q. coccifera and Quercus branti. Condensed tannin contents of oak nuts were ranged from 1.48% to 3.50%. Condensed tannin contents of oak nuts from Q. coccifera and Q. branti were significantly higher than those of Q. suber and Q. ithaburensis ssp. macrolepis. As conclusion, species had a significant effect on the chemical composition ME, OMD and methane production of oak nuts. Oak from Q. ithaburensis ssp. macrolepis will provide nut with quite digestible and high ME for ruminant animals although it is likely that animal consumed oak nut from Q. ithaburensis ssp. macrolepis will produce more methane and more pollutant to environment. However further investigations are required to determine the effect of oak species on the feed intake and animal performance.

Determination of polyphenol and crude nutrient content and nutrient digestibility of dried and ensiled white and red grape pomace cultivars

The present study aimed to determine the nutrient and energy content of fresh and ensiled grape pomace (GP) from different grape varieties originating from Germany, and to estimate the feed value of dried white, dried red and ensiled white GP by calculating nutrient digestibility and the content of metabolisable energy (ME) and net energy lactation (NEL) measured in sheep as a ruminant model. GP from red cultivars had higher contents of organic matter (OM), crude protein (CP), ether extract (EE), crude fibre (CF), total phenolic contents (TPC) and ME, whereas the concentrations of ash and sugar were lower than from white cultivars. Compared with untreated GP, ensiled GP had increased concentrations of CP (+19%), ether extract (EE; +23%) and CF (+12%) and a higher ME content (+7%) and markedly decreased concentrations of sugar (−99.6%) and TPC (−48%). The concentrations of dry matter, OM and ash were not different between ensiled and fresh GP. Compared with dried GP, ensiled GP had a higher nutrient digestibility (OM, +32%; CP, +43%; CF, +46%; neutral detergent fibre [NDF], +54%; acid detergent fibre [ADF], +69%) and higher energy values (ME, +16%; NEL, +19%). The digestibility of OM, CP, EE and CF and the energy content were higher for dried red than for dried white GP, whereas the digestibility of NDFOM and ADFOM was lower for dried red than dried white GP. In conclusion, the results show that both red and white GP are suitable dietary sources for enrichment with TPC. Furthermore, compared with drying ensiling of GP improves the feeding value of GP and is a good possibility of preserving the seasonally produced by-product of winemaking for ruminant feeding.

Shrub encroachment of Iberian dehesas: implications on total forage productivity

The Iberian dehesa, a grazed Mediterranean open woodland, is an outstanding example of a silvopastoral system. Shrub encroachment has been proposed as an effective method to facilitate natural tree regeneration and ensure the sustainability of silvopastoral systems. At the same time, shrubs can affect both pasture understory and tree overstory production. The effects of varying intensities of shrub encroachment on the productivity of four forage components of this system—pasture, acorns, shrub browse and tree browse—were tested and the overall metabolisable energy (ME) under different scenarios of vegetation structure was calculated. Two common shrub species with contrasting plant architectures and ecological functions were studied as models: Cistus ladanifer and Retama sphaerocarpa. Cistus negatively affected acorn, tree browse and pasture production, whereas Retama positively affected pasture and browse production and was neutral for acorn production. The highest ME values were found when tree cover was ca. 70 % and C. ladanifer cover was low or R. sphaerocarpa cover was medium. The authors recommend conserving and promoting patched three-layered plots in Iberian dehesas and similar extensive silvopastoral systems where certain shrub species could simultaneously encourage the sustainability of these systems and reinforce (with R. sphaerocarpa) or maintain (with C. ladanifer) their productivity.

Effect of organic zinc supplementation on growth, nutrient utilization,and plasma zinc status in lambs

Two experiments were conducted to investigate the effect of supplemental zinc (Zn) on performance, nutrient digestibility, and plasma Zn status in Zandi lambs. In experiment 1, 18 male lambs (BW = 21.30 ± 0.55 kg) were fed a basal diet containing 22.8 mg Zn/kg dry matter (DM) with no supplemental Zn (control) or 20 mg of supplemental Zn/kg of DM from Zn sulfate (ZnS) or Zn peptide (ZnP). Average daily gain and dry matter intake were higher for the lambs fed the diet supplemented with ZnP. Feed conversion ratio was significantly (P < 0.05) lower in the ZnP group compared to the control and ZnS groups. In experiment 2, an in vitro gas production technique was used to evaluate the effects of zinc source on the gas production parameters. Rate of gas production after 6 h and total production of gas after 24 and 48 h did not differ between groups. In vitro DM digestibility, short-chain fatty acids, and ME content were increased (P < 0.05) by ZnP supplementation when compared to the ZnS and control groups. The results of this study showed that feeding ZnP improves performance and digestibility of DM and could result in higher metabolizable energy and short-chain fatty acid yield.

Níveis de inclusão do farelo de arroz parboilizado em rações para leitões na fase de creche

Foram conduzidos dois ensaios para avaliar a utilização do farelo do farelo integral de arroz parboilizado (FIAP) em rações para leitões na fase de creche. No primeiro, foram utilizados 14 suínos machos castrados para a avaliação nutricional do ingrediente em ensaio de digestibilidade. O delineamento experimental foi o inteiramente ao acaso, com dois tratamentos e sete repetições por tratamento. O FIAP apresenta 17,15% de PB, elevado teor em fibras (33,75% de FDN e 15,91% de FDA) e teor reduzido de energia metabolizável, próximo a 2320kcal/kg. No segundo experimento, foram utilizados 60 leitões machos castrados, com o objetivo de avaliar o desempenho zootécnico, a ocorrência de diarreia e a viabilidade econômica do farelo de arroz parboilizado. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos (0, 4, 8, 12 e 16% de inclusão) e seis repetições. Não houve diferença significativa entre o tratamento controle e os tratamentos teste (P&gt;0,05), assim como para a análise de regressão, em que os crescentes níveis de inclusão do ingrediente não resultaram em piora no desempenho (P&gt;0,05). O FIAP pode ser incluído até o nível de 16% em rações para leitões na fase de creche.

Effect of ambient temperature on nutrient digestibility and nitrogen balance in sheep fed brown-midrib maize silage

The aim of the experiment was to determine the impact of heat stress on nutrient digestibility and nitrogen balance in sheep fed silages differing in fibre quality. The digestibility trial was conducted at three different ambient temperatures (15°C, 25°C and 35°C for 24 h/d). The tested brown-midrib maize (Bm) silage had a higher nutrient digestibility, except for ether extract (EE) and a higher metabolisable energy (ME) content than the control maize (Con) silage. Nitrogen (N) excretion with faeces was higher but N excretion with urine was lower for sheep fed Bm silage, subsequently N balance did not differ between the two silages. Temperature had no effect on nutrient digestibility, except for crude protein (CP), but N excretion with urine was lower at elevated temperatures. A diet by temperature interaction was found for dry matter (DM) and organic matter (OM) digestibility. When the ambient temperature increased from 15°C to 25°C, the DM and OM digestibility increased in animals fed Con silage, but decreased in animals fed Bm silage. Concomitantly, ME estimated from digestible nutrients was higher for Bm than for Con at 15°C, but no differences were found at 25°C and 35°C. Effects of diet by temperature interaction, furthermore, were observed for EE and CP digestibility. Therefore, forage quality has to be considered when feeding heat-stressed animals.

Farelo integral de arroz parboilizado submetido a armazenamento prolongado para alimentação de codornas de corte

O objetivo deste trabalho foi avaliar a estabilidade oxidativa do farelo integral de arroz parboilizado (FIAP) durante o armazenamento e os efeitos do seu uso na alimentação de codornas de corte. Foram utilizados 245 animais com sete dias de idade, de ambos os sexos, distribuídos em delineamento inteiramente casualizado, com cinco tratamentos, em arranjo fatorial 2x2+1, e sete repetições de sete aves. Avaliaram-se os seguintes tratamentos: dieta controle, sem adição de FIAP; e níveis de inclusão, na dieta controle, de 10 e 20% de FIAP armazenado por 180 dias (FIAPA) ou de FIAP novo (FIAPN). Houve oxidação lipídica do FIAP durante o armazenamento, e o índice de acidez foi de 4,25 e 63,50 (% em ácido oleico) e o de peróxido foi de 15,64 e 38,28 meq kg-1 para FIAPN e FIAPA, respectivamente. A inclusão do FIAP resultou em menor digestibilidade da matéria seca e do nitrogênio e em maior valor de energia metabolizável da ração, em comparação à ração controle. A inclusão de 20% de FIAPA resultou em menor energia metabolizável da ração do que a adição do FIAPN. As inclusões não influenciaram desempenho, características da carcaça, pesos relativos do fígado e do pâncreas, e crescimento e qualidade óssea. O FIAPA, mesmo com rancidez, pode ser utilizado na alimentação de codornas de corte em níveis de até 20% de inclusão.

Monthly metabolisable energy feed requirements of crossbred ewes in accelerated and traditional lamb production systems

The annual metabolisable energy (ME) feed requirements and patterns of monthly ME requirements for ewe maintenance, gestation, lactation and lamb growth to weaning were evaluated for 1175 crossbred ewes over 4 years at two sites (Cowra and Wagga Wagga). The study involved three lamb production systems: accelerated 8-monthly joinings, with two flocks joined 4 months apart (Ac8), spring joining with an autumn backup joining (SpB), and annual autumn joining (AuA). The Ac8 and SpB systems were evaluated at Cowra and the SpB and AuA systems were evaluated at Wagga Wagga. Two genotypes of ewes, Border Leicester × Merino (BLM) and Hyfer (Dorset × Merino composite), were used at both sites, with natural joinings to Dorset, Suffolk or Hyfer rams. The ewe liveweight, reproduction and lamb production data from individual ewes in the experiment were used to calculate monthly ME requirements using derived simplified equations for ewe maintenance, gestation, lactation and lamb growth to weaning. Annual ME, dry sheep equivalent (DSE = maintenance for a 50-kg, 3.5-year-old ewe = 3030 MJ) and weight of lamb weaned per DSE were analysed and the monthly pattern of ME components presented graphically. The ewes in the Ac8 system had 11% higher ME than those in the SpB system because of their considerably higher annual lambing performance, which resulted in 16–47% greater efficiency of the Ac8 compared with the SpB system when expressed as weight of lamb weaned per DSE. There was also a lower proportion of ME for ewe maintenance in the Ac8 (58%) than SpB or AuA (68%) systems. There was little difference in the annual feed requirements or DSE for ewes in the SpB and AuA production systems, although ewes in the AuA system weaned 9–28% more weight of lamb per DSE than the SpB ewes because of their higher lambing performance. The differences in ME and DSE between the BLM and Hyfer ewes were relatively small and mainly reflected the differences in lambing performance of the genotypes in the various production systems. The seasonal pattern of ME for the AuA and SpB systems showed a sharp increase from the last month of pregnancy to a high peak at weaning with a relatively low requirement for the rest of the year. Under the Ac8 system the ME requirements were more consistent throughout the year and at a lower level than the peak for the other systems. The results highlight the possible increased efficiency from an accelerated lambing system, provided the seasonal feed requirements throughout the year can be provided cost effectively.

Use of diploid and tetraploid hulled wheat genotypes for animal feeding

Einkorn and emmer wheat are still cultivated in the mountainous areas of Turkey. They are resistant to biotic and abiotic stress conditions and are routinely used as food stuffs due to reasonable dietary fiber rate and vitamin and micronutrient content. Therefore, the present study was conducted to determine the feed potential of einkorn and emmer wheat populations. A total of 17 hulled wheat populations collected from different provinces of Turkey were studied during the years 2012 and 2013. Experiments were carried out in randomized complete block design with 3 replications to investigate grain yield, harvest index, chemical composition, and gas and methane production of the grain. Grain yield varied between 2.477 and 4.617 t ha-1 , harvest index between 27.55% and 36.03%, crude protein (CP) between 6.69% and 16.22%, neutral detergent fiber (NDF) between 25.99% and 31.99%, acid detergent fiber (ADF) between 14.35% and 19.05%, crude oil (CO) between 1.33% and 2.05%, crude ash (CA) between 4.23% and 5.22%, metabolizable energy (ME) between 2.58 and 2.25 Mcal kg-1 DM, organic matter digestibility (OMD) between 65.59% and 72.73%, and gas production (GP) between 46.01 and 52.22 mL. While einkorn populations had higher ME, OMD, CP, and CO content values, emmer wheat populations had higher ADF and NDF rates. Moreover, there were significant variations in gas and methane production in all hulled wheat populations. Genotype-trait biplot analysis clearly indicated the variation limits of NDF, ADF, CP, OMD, ME, methane, GP, CO, and CA of hulled wheat populations. There were also significant linear relationships between CP and ME (0.585) and OMD (0.613); between CO and GP (0.513); and between GP and ME (0.623) and OMD (0.696). It was concluded that with regard to higher yield and digestibility, these hulled wheat populations could be used as basic germplasm for breeding of new einkorn and emmer wheat cultivars to be used as alternative feedstuff.

The effect of soy oligosaccharide extraction on diet digestibility, faecal characteristics, and intestinal gas production in dogs

This study aimed at evaluating the coefficients of total tract apparent digestibility (CTTAD) and metabolisable energy (ME) content of dog foods containing different soybean protein products, as well as the faecal characteristics and intestinal gas production of dogs consuming these diets. The following soybean products were added at 300g/kg of diet: soybean meal (SBM), soy protein concentrate (SPC) with 600g crude protein (CP)/kg (SPC600), SPC with 700gCP/kg (SPC700), hydrolysed SPC700 (HSPC), and soy protein isolate (SPI). The CTTAD and faecal characteristics were determined in six dogs according to a 6×6 Latin square design. Intestinal gas production was evaluated by radiography of 16 dogs fed the reference diet and diets containing 300g SBM, SPC700, or SPI/kg. Crude protein digestibility of SBM, SPC600, SPC700, HSPC, and SPI was 0.898, 0.839, 0.852, 0.906, and 0.988, respectively. Soy protein isolate presented the highest ME content (21.26MJ/kg, P<0.001) and SPC600, the lowest ME (14.15MJ/kg, P<0.001). Dogs fed the reference and the SPI diets presented harder faeces and higher faecal pH (P<0.001). Soybean meal produced the highest intestinal gas volume (P<0.05), while there was no difference among the other treatments (P>0.05). The removal of soybean oligosaccharides reduces intestinal gas production in dogs. However, soybean ethanol-insoluble fibres must be removed to increase protein digestibility and ME content, as well as to improve the faecal texture of dogs.

Influence of Apple and Citrus Pectins, Processed Mango Peels, a Phenolic Mango Peel Extract, and Gallic Acid as Potential Feed Supplements on in Vitro Total Gas Production and Rumen Methanogenesis

Several food processing byproducts were assessed as potential feed and feed supplements. Since their chemical composition revealed a high nutritional potential for ruminants, the Hohenheim in vitro gas test was used to investigate total gas, methane, and volatile fatty acid production as well as protozoal numbers after ruminal digestion of different substrate levels. Processing byproducts used were low- and high-esterified citrus and apple pectins, integral mango peels, and depectinized mango peels. In addition, the effect of a phenolic mango peel extract and pure gallic acid was investigated. The highest decrease in methane production (19%) was achieved by supplementing high levels of low-esterified citrus pectin to the hay-based diet. Interestingly, total gas production was not affected at the same time. Showing valuable nutritional potential, all byproducts exhibited, e.g., high metabolizable energy (11.9-12.8 MJ/kg DM). In conclusion, all byproducts, particularly low-esterified citrus pectin, revealed promising potential as feed and feed supplements.

Changes of haematic parameters, redox status and mitochondrial complex activity in the heart and liver of broilers fed with different density diets under low ambient temperature

This experiment was conducted to investigate the influence of dietary nutrient density on haematic parameters, oxidative status and mitochondrial complex activity in the heart and liver of broilers under low ambient temperature. Eight-day-old male ROSS-308 chickens were randomly divided into two treatments fed with normal (control) and high metabolizable energy (ME) and crude protein density (H) diets. A high nutrient density diet increased body weight gain and reduced the feed conversation ratio during the first 3 weeks. Increased ascites-related mortality (weeks 4 to 6), right ventricle/total ventricle (week 6), blood haemoglobin (weeks 2 and 4) and mean corpuscular haemoglobin (week 2) were observed in treatment H. Levels of malonaldehyde and protein carbonylation were increased at week 4, and activities of glutathione peroxidase at week 4 and CuZn superoxide dismutase and catalase at week 6 were decreased in the heart; only malonaldehyde (week 6) was increased in the liver in treatment H. Relative mRNA expression of hypoxia inducible factor-1 (heart) was increased and heme oxygenase-1 (heart and liver) was decreased at week 4 in broilers fed with high ME and protein diet. Activities of mitochondrial complex III and IV (week 6) in the heart, and complex I (week 6) and complex III and IV (week 4) in the liver were decreased in treatment H. In conclusion, high levels of dietary ME and protein resulted in oxidative stress and high incidence of ascites in broilers under low ambient temperature. Heart dysfunction was primarily attributed to ascites development, in which oxidative injury and inhibition of mitochondrial complex activity were involved.

The Metabolizable Energy Value, Standardized Ileal Digestibility of Amino Acids in Soybean Meal, Soy Protein Concentrate and Fermented Soybean Meal, and the Application of These Products in Early-weaned Piglets.

Three experiments were conducted to evaluate the metabolizable energy (ME) value, standardized ileal digestibility (SID) of amino acids (AA) of soybean meal (SBM), soy protein concentrate (SPC) and fermented soybean meal (FSBM), and the application of these products in early-weaned piglets. In Exp. 1, four barrows with initial body weight (BW) of 14.2±1.4 kg were used in a 4×4 Latin square design. The diet 1 contained corn as the only energy source. The other three diets replaced 25% of corn in diet 1 with one of the three soybean products, and the digestable energy (DE) and ME contents were determined by difference. In Exp. 2, four barrows (initial BW of 18.2±1.5 kg) were fitted with ileal T-cannulas and allotted to a 4×4 Latin square design. Three cornstarch-based diets were formulated using each of the soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, ninety six piglets (initial BW of 5.6±0.9 kg) weaned at 21±2 d were blocked by weight and assigned to one of three treatments for a 21-d growth performance study. The control diet was based on corn and SBM, the two treatments’ diets contained either 10% SPC or FSBM and were formulated to same SID lysine to ME ratio of 3.6 g/Mcal. The results showed that the ME content of SPC was greater than SBM (p<0.05). The SID of most AA in SPC was greater than the SID of AA in SBM (p<0.05). For the essential AA, the SID of histidine, isoleucine, leucine, lysine and threonine in FSBM were greater than in SBM (p<0.05). Even though they were fed same SID lysine to ME ratio of 3.6 g/Mcal diets, pigs fed SPC and FSBM diets had greater weight gain, G:F (p<0.05) and better fecal score (p<0.05) than pigs fed SBM diet. In conclusion, SPC showed a higher ME content and SID of AA than the SBM. SID of some essential AA in FSBM was higher than SBM and was similar with SPC. But the lower antigenic proteins and anti-nutritional factors content in SPC and FSBM may be the main factors affecting the performance of early-weaned piglets rather than the increased ME content and SID of AA.

Earlier Metabolizable Energy Intake Level Influences Heat Production during a Following 3-Day Fast in Laying Hens.

The present study was conducted to estimate energy requirements for maintenance in laying hens by using indirect calorimetry and energy balance. A total of 576 28-wk-old Nongda-3 laying hens with dwarf gene were randomly allocated into four ME intake levels (86.57, 124.45, 166.63 and 197.20 kcal/kg body weight (BW)0.75 per d) with four replicates each. After a 4 d adaptation period, 36 hens from one replicate were maintained in one of the two respiration chambers to measure the heat production (HP) for 3 d during the feeding period and subsequent 3 d fast. Metabolizable energy (ME) intake was partitioned between heat increment (HI), HP associated with activity, fasting HP (FHP) and retained energy (RE). The equilibrium FHP may provide an estimate of NE requirements for maintenance (NEm). Results showed that HP, HI and RE in the fed state increased with ME intake level (p<0.05). Based on the regression of HP on ME intake, the estimated ME requirements for maintenance (MEm) was 113.09 kcal/kg BW0.75 per d when ME intake equals HP. The FHP was decreased day by day with the lowest value on the third day of starvation. Except for lowest ME intake level, the FHP increased with ME intake level on the first day of starvation (p<0.05). The FHP at the two higher ME intake levels were greater than that at the two lower ME intake levels (p<0.05) but no difference was found between the two lower ME intake levels. Linear regression of HP from the fed state to zero ME intake yielded a value of 71.02 kcal/kg BW0·75 per d, which is higher than the extrapolated FHP at zero ME intake (60.78, 65.23 and 62.14 kcal/kg BW0.75 per d for the first, second and third day of fasting, respectively). Fasting time, lighting schedules, calculation methods and duration of adaptation of hens to changes in ME intake level should be properly established when using indirect calorimetry technique to estimate dietary NE content, MEm and NEm for laying hens.

Classification of Distinct Seed Carbohydrate Profiles in Soybean

Soybeans are an important source of protein-rich meal for livestock feed formulations. Recent changes in the cost of commodity-based sources of metabolizable energy (ME) inputs has put pressure on soybean meal to deliver both protein and ME in feed formulations. The non-oil fraction of soybean contains approximately 12% soluble carbohydrates, principally sucrose, raffinose, and stachyose. Of these carbohydrates, only sucrose is positive for ME. Both raffinose and stachyose, belonging to the raffinose family of oligosaccharides (RFOs), are considered antinutritional because of the negative consequences of their fermentation in the gut of monogastric animals when RFOs are consumed in the diet. Therefore, there is an interest in improving soybean seed composition so that it contains higher ME and fewer antinutritional components by increasing the sucrose content while lowering the RFOs. Several soybean lines have been discovered that contain altered levels of RFOs, and recent molecular genetic investigations have shown the phenotype to be caused by mutations in a raffinose synthase 2 (RS2) gene encoding the enzyme that is the committed step for RFO biosynthesis. The objective of this research was to determine the variation in carbohydrate profile for different soybean lines grown in a single location containing one of three different alleles of the RS2 gene. The results indicate that, although there is variation in the carbohydrate profiles for each line, different lines with the same RS2 genotype tend to produce a characteristic carbohydrate profile. Although the carbohydrate profile for each RS2 genotype class was consistent in different genetic backgrounds under two conditions grown at one location, more research will be necessary to determine the environmental stability of the carbohydrate profiles in multiple locations over different years.