Metabolizable Content Research Articles

Effect of molasses on nutritive value and in-vitro digestibility of elephant grass silage

Abstract Ensiling preserving a forage crop and its nutrients to feed later on as silage. In this study, elephant grass was ensiled with varying levels of molasses as an additive to evaluate its effect on the nutritive value and in-vitro digestibility of the silage. Four treatments of Pennisetum purpureum grass silage were produced with the inclusion of molasses at 0 (T1), 2.5 (T2), 5 (T3), and 7.5 % (T4) inclusion levels. Elephant grass ensiled with higher levels of molasses inclusions (T3, and T4) had significantly higher (p < 0.05) dry matter, crude protein, nitrogen-free extract, and lactic acid than T1 and T2 silages. However, T1 and T2 silages had significantly higher (p < 0.05) crude fibre and ash contents. Furthermore, silage without molasses inclusion (T1) had significantly higher (p < 0.05) in most of the fibre fractions compared to other silages in this study. At 6 and 15 hours, there were no significant differences (p > 0.05) in the means of in-vitro gas production. However, gas production was significantly higher (p < 0.05) in silages with the inclusion of additives (T4, T3, and T2) at 9, 12, 18, 21, and 24 hours of incubation. Conspicuously, silages containing graded levels of molasses as an additive had significantly higher (p < 0.05) digestibility and organic matter digestibility than the silage without molasses. The methane gas and metabolisable contents were significantly higher (p < 0.05) in T3 and T4 silages than T1 and T2 silages. However, T3 had significantly the highest (p < 0.05) gas volume followed by T2, T4, and T1 silages. It can be concluded that our H1 hypothesis was confirmed and the inclusion of molasses as an additive in elephant grass silage resulted in improved dry matter, crude protein, lactic acid contents, reduced fibre fractions, and superior in-vitro digestibility values as well as relatively better gas production by the silage.

Effects of variety and storage duration on the nutrient digestibility and the digestible and metabolisable energy content of maize fed to growing pigs

ABSTRACTThe objective of this research was to determine the effects of variety and storage duration on the nutrient digestibility and the digestible (DE) and metabolisable (ME) energy content in maize when fed to growing pigs. Four maize varieties (LS1, LS2, LS3 and LS4) were hand-harvested from the same growing area in China in early October of 2012. The samples were sun dried to about 14% moisture content and then stored in the warehouse of the Fengning Pig Experiment Base at China Agricultural University for 0, 3 or 10 months. Twenty-four barrows of about 33 kg body weight were used and allotted to a completely randomised block design with four diets and six replicate pigs per diet. Pigs were individually housed in metabolic crates. The four experimental diets were formulated by mixing 96.8% of each variety of maize with 3.2% vitamins and minerals. A 5-day collection period followed a 7-day diet acclimation period. The results indicated that the DE and ME contents of maize and the apparent total tract digestibility (ATTD) of organic matter (OM), dry matter, gross energy (GE), neutral detergent fibre, acid detergent fibre (ADF), crude protein (CP) and ether extract (EE) were significantly (p < 0.05) influenced by maize variety and storage duration. With an extension of storage duration from 0 to 10 months, the DE and ME of maize and the ATTD of OM, GE, ADF, CP and EE changed in a quadratic manner (p < 0.05), and 3 months of storage exceeded 0 months of storage by 1.84%, 1.43%, 0.31%, 0.32%, 15.37%, 2.11% and 5.02%, respectively. The DE, ME of maize and the ATTD of OM, GE, ADF, CP and EE decreased by 3.67%, 6.00%, 0.97%, 1.40%, 30.54%, 3.92% and 20.93%, respectively, at 10 months of storage compared to 3 months of storage. No interaction was observed between maize variety and storage duration in DE and ME contents in maize. In conclusion, under the conditions of this study, most of the nutrient digestibility and the DE and ME contents of maize increased from 0 to 3 months and decreased from 3 to 10 months.

The effect of inclusion level and basal diet on the determination of the digestible and metabolisable energy content of soybean oil and its digestibility when fed to growing pigs

This experiment was conducted to determine the effect of inclusion level and type of basal diet on the digestible (DE) and metabolisable (ME) energy content of soybean oil and its digestibility when fed to growing pigs. Thirty-six barrows (Duroc × Landrace × Yorkshire weighing 34.2 ± 3.8 kg) were randomly allotted to a 2 × 3 factorial arrangement involving two basal diets and three levels of soybean oil (0%, 5% and 10%). One basal diet was based on corn and soybean meal. The other basal diet was based on corn starch and casein. The barrows were housed in individual metabolism crates to facilitate separate collection of faeces and urine, and were fed the assigned test diets at 4% of initial bodyweight per day. A 5-day total collection of faeces and urine followed a 7-day diet-adaptation period. The DE and ME contents of soybean oil were significantly affected by the dietary inclusion level (P &lt; 0.05), but not by the type of basal diet. The DE contents of soybean oil at the 5% and 10% inclusion level were 34.99 and 37.63 MJ/kg, respectively, for the corn–soybean meal basal diet and 33.72 and 35.21 MJ/kg, respectively, for the corn starch–casein basal diet. The respective corresponding values for ME were 33.91, 37.07, 33.06 and 34.83 MJ/kg. The DE values calculated from regression equation were 38.05 and 37.85 MJ/kg, respectively, for corn–soybean meal and corn starch–casein basal diet. The DE value calculated from regression equation was greater than the values determined from the difference method for corn starch–casein basal diet. The value of endogenous loss for acid-hydrolysed ether extract was greater (P &lt; 0.05) for corn–soybean meal basal diet than for corn starch–casein (13.06 g/kg of dry matter intake for corn–soybean meal basal diet and 1.37 g/kg of dry matter intake for corn starch–casein basal diet, respectively). The values of the true total tract digestibility and apparent total tract digestibility of soybean oil determined from the corn–soybean meal basal diet were not different from those determined from the corn starch–casein basal diet (true total tract digestibility: 97.1% and 95.4%; apparent total tract digestibility: 95.8% and 95.3%, respectively). In conclusion, the DE and ME values of soybean oil are affected by its inclusion level but not by basal diet. The type of basal diet did not affect the digestibility of soybean oil, but affected the endogenous loss of acid-hydrolysed ether extract for soybean oil.

Farklı Meşe Türlerinden Elde Edilen Palamutlarının Potansiyel Besleme Değeri ve Kondense Tanen İçerikleri

Summary The potential nutritive values of acorns of Quercus suber, Quercus branti, Quercus coccifera, Quercus cerris and Quercus infectoria were estimated by chemical composition and in vitro gas production technique. Acorns collected at least 10 different trees in three experimental plots. There were significant (P 0.5) differences in the potential gas production of acorn among oak species when incubated in the absence of PEG, there is significant (P<0.001) differences in the potential gas production of acorn among oak species when incubated in the presence of PEG. Although the estimated organic matter (OMD) and metabolisable (ME) contents of acorn for Q. suber and Q. infectoria were significantly (P<0.001) higher than those for Q. branti, Q. coccifera and Q. cerris when incubated in the absence of PEG, the estimated OMD and ME contents of acorn for Quercus cerris and Q. infectoria were significantly lower than those for Q. suber, Q. branti and Q. coccifera when incubated in the presence of PEG. The improvement in gas production, OMD and ME in the presence of PEG emphasizes the negative effect of tannins on digestibility. As a conclusion, oak acorns have potential nutritive values for ruminant animals such as sheep and goat since acorns have high starch, OMD and ME but low level of CT contents. However these results obtained in the current study should be supported by in vivo feeding experiments.

The combined effects of animal species (sheepversuscattle) and level of feeding on digestible and metabolizable energy concentrations in grass-based diets of cattle

AbstractA total of 317 dairy and beef cattle, offered grass silage-based diets, have been subjected to energy metabolism measurements in calorimetric chambers in 11 feeding experiments at this Institute. In addition the silages (no. = 33) were also given individually to sheep as a sole food at maintenance feeding level for measurement of energy intake and outputs (faeces and urine). The digestible (DE) and metabolizable (ME) energy concentrations of mixed diets for sheep at maintenance were estimated using these measured silage data, predicted silage methane energy output and tabulated energy values of concentrates. The objective of the present study was to use treatment mean data (no. = 59), derived from the cattle (production level) (MEprod or DEprod) and the sheep (maintenance level) (MEmaint or DEmaint), to evaluate the combined effects of animal species and level of feeding on dietary ME or DE concentration. The mean-square prediction error technique and the sensitivity test both indicated that there was little bias derived from the deviation of the slope (line bias) when relating MEprod (DEprod) with cattle to MEmaint (DEmaint) with sheep. Relating feeding level to the decline in ME or DE concentration (from maintenance to production level) revealed that the constant had no significant effect on the relationship, suggesting that there was little difference in dietary ME or DE concentration between sheep and cattle when given food at maintenance. ME d and DE d were significantly related to MEmaint and DEmaint (P &lt; 0001) respectively. These two relationships were however influenced (P &lt; 0001) by level of feeding above maintenance (FL-1). There was little effect of silage DM proportion in the total diets (S/T) on the depression of ME concentration from maintenance to production levels, while this effect on the depression of DE concentration was significant (P &lt; 0001). Therefore, the following two equations are recommended to calculate MEprod and DEprod concentrations respectively for cattle using data obtained with sheep at maintenance. Alternatively, with each unit increase in feeding level above maintenance, dietary ME and DE concentrations respectively were reduced by proportionately 0016 and 0025 for grass silage-based diets, irrespective of the effect of forage proportion on the latter. MEprod = [1 068 - 0019 ✕ (FL-1)] ✕ MEmaint - 0·755 DE d = [0·891 + (-0027 + 0018 ✕ S/T) ✕ (FL-1)] ✕ DEmaint + 1·355

Energy and nutrient use of palm kernels, palm kernel meal and palm kernel oil in diets for growing pigs

A metabolism experiment was conducted with 13 gilts over four periods to investigate the effects of age or weight of pigs, level of inclusion and methods of estimation of apparent digestible (DE) and metabolizable (ME) energy and nutrient digestibility of full-fat palm kernels (FFPK), recombined palm kernel oil and meal (OPKM) and palm kernel oil (PKO). Each palm kernel product was evaluated at levels equivalent to added oil of 40, 80 and 120 g kg −1 in a basal diet. Extracted palm kernel meal (PKM) was also evaluated in the basal diet at the same level as in OPKM. Thus, 13 treatments arranged in four blocks (time periods) constituted the experimental data analysed using a randomised complete block design. Digestible energy and ME contents and apparent digestibility of nitrogen (ADN), dry matter (ADD) and oil (AOD - employing two oil analytical methods) of palm kernel products were estimated by single level assay and by regression with the latter yielding DE values of 40.2, 19.5, 22.1 and 13.1 MJ/kg DM for PKO, FFPK, OPKM and PKM, respectively. The corresponding values for AOD were 1.08, 0.93, 1.03 and 0.88. While the level of inclusion and pig weight (over the range 40–76 kg) did not significantly affect dietary energy and nutrient digestibility of palm kernel products, the form of oil inclusion had considerable effect with OPKM being better utilized than FFPK. Digestibility of oil in the palm kernel products measured by the ether extract (EE) method was, in general, significantly higher than that estimated by the acid ether extract (AEE) procedure. The results suggest the necessity for digestibility coefficients of oils and fats in oil bearing ingredients to be re-evaluated in the light of the currently applied analytical method as figures obtained using the traditional ether extract method may not be applicable to the true nutritional value of feed ingredients and consequently may lead to imprecise diet formulation.

Determinação dos valores de energia e do balanço de nitrogênio de alguns alimentos para leitões na fase inicial

Este trabalho foi realizado para obter valores de energia digestível (ED) e metabolizável (EM) de quatorze alimentos, em cinco experimentos, utilizando-se 144 leitões com 28 dias de idade e peso médio de 9,42±0,76 kg. O teor de energia digestível (ED) e o de energia metabolizável (EM) foram determinados por intermédio do método de coleta total de fezes e urina. As fontes de proteína provenientes do leite foram superiores aos subprodutos da soja, com relação à digestibilidade da energia e da proteína. Entre os subprodutos da soja, a proteína concentrada e a proteína texturizada apresentaram os maiores valores de digestibilidade da energia e a soja integral extrusada, os menores. A digestibilidade da matéria seca e da energia do milho e do farelo de soja com 46,5% de proteína bruta foi semelhante à observada em avaliações com suínos adultos, indicando que a capacidade dos leitões jovens para digerir estes dois alimentos foi semelhante à dos suínos adultos. Houve redução da relação EM/ED, em virtude do aumento do teor de proteína e do desequilíbrio entre os aminoácidos da dieta e diminuição da relação entre energia bruta e N excretados na urina, com aumento do teor de proteína da dieta e vice-versa. Estes dados indicam a necessidade de se desenvolverem fatores de correção para EM específicos para diferentes grupos de alimentos e condições de experimentação.

Effect of body weight on net energy value of feeds for growing pigs.

Digestible (DE), metabolizable (ME), and net (NE) energy values of seven diets were measured in castrated male pigs of 45 (Stage 1), 100 (Stage 2), or 150 (Stage 3) kg BW. Diets were prepared from a basal diet supplemented with cornstarch, or sucrose, or a protein mixture (referred to here as protein), or rapeseed oil, or a mixture of fibrous ingredients (referred to as fiber), or rapeseed oil+fiber. Diets were fed at similar levels (x maintenance) at the three stages. Heat production at different feeding levels, as measured by indirect calorimetry, allowed calculation of energy retained by each pig (equal to ME intake minus heat production) and an estimate of fasting heat production of all pigs (360 kcal/kg BW.42). Net energy intake was then calculated for each pig as retained energy plus 360 x BW.42. The amounts of DE digested before the end of the ileum (DEi) and in the hindgut (DEh) were measured. Formulation of diets allowed calculation of energy values of the ingredients added to the basal diet. Digestibility and metabolizability of diets increased significantly from Stages 1 to 3, with higher variations for low-energy diets. The NE:ME ratio (k, %) and dietary NE content were not affected (P > .05) by stage of growth. On average, k was 75%, with higher values for diets containing rapeseed oil or starch (77%) and lower estimates for the fiber diet (72%). As a consequence, k was approximately 90, 82, 80, 72, and 60% for rapeseed oil, cornstarch, sucrose, protein, and fiber, respectively. These values are consistent with the lower k value for ME from DEh (57 vs 78% for DEi). Present data confirm that the hierarchy between feeds is dependent on the energy system (DE vs ME vs NE) and that the NE concept is superior in predicting the "true" energy value. The present results combined with previous ones show that, under practical conditions, the same NE prediction equations based on digestible nutrient contents, or preferably DE or ME contents, can be applied at all stages of growth in pigs. However, attention should be paid to factors such as BW or feeding level that affect digestibility and metabolizability of feeds markedly. The effects are the most important for ingredients.