Nutritional evaluation of high-digestible sorghum for pigs and broiler chicks

Prediction of available energy and amino acid digestibility of Chinese sorghum fed to growing-finishing pigs

Two experiments were conducted to determine digestible energy (DE), metabolizable energy (ME), as well as the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 sorghum samples fed to pigs. In experiment 1, 22 crossbred barrows (Duroc × Yorkshire × Landrace, Initial body weight [BW]: 70.0 ± 1.8 kg) were selected and allotted to a replicated 11 × 3 incomplete Latin square design, including a basal diet and 10 sorghum energy diets and three consecutive periods. Each period had 7 d adaptation and 5 d total feces and urine collection. The DE and ME were determined by the total collection and the difference method. In experiment 2, 22 crossbred barrows (Duroc × Yorkshire × Landrace, Initial BW: 41.3 ± 1.2 kg) that had a T-cannula installed in the distal ileum were assigned to a replicated 11 × 3 incomplete Latin square design, including an N-free diet and 10 sorghum diets. Each period had 5 d adaptation and 2 d ileal digesta collection. The basal endogenous N losses were measured by the N-free diet method. All diets in experiment 2 were added 0.30% titanium dioxide as an indigestible marker for calculating the ileal CP and AA digestibility. On an as-fed basis, the DE and ME contents in sorghum were 3,410 kcal/kg (2,826 to 3,794 kcal/kg) and 3,379 kcal/kg (2,785 to 3,709 kcal/kg), respectively. The best-fit prediction equation for DE and ME were DE = 6,267.945 - (1,271.154 × % tannin) - (1,109.720 × % ash) (R2 = 0.803) and ME = 51.263 + (0.976 × DE) (R2 = 0.994), respectively. The SID of CP, Lys, Met, Thr, and Trp (SIDCP, SIDLys, SIDMet, SIDThr, and SIDTrp) in 10 sorghum samples were 78.48% (69.56% to 84.23%), 74.27% (61.11% to 90.60%), 92.07% (85.16% to 95.40%), 75.46% (66.39% to 80.80%) and 87.99% (84.21% to 92.37%), respectively. The best prediction equations for SID of CP and the first four limiting AAs were as following: SIDCP = 93.404 - (21.026 × % tannin) (R2 = 0.593), SIDCP = 42.922 - (4.011 × % EE) + (151.774 × % Met) (R2 = 0.696), SIDLys = 129.947 - (670.760 × % Trp) (R2 = 0.821), SIDMet = 111.347 - (232.298 × % Trp) (R2 = 0.647), SIDThr = 55.187 + (3.851 × % ADF) (R2 = 0.609) and SIDTrp = 95.676 - (10.824 × % tannin) (R2 = 0.523), respectively. Overall, tannin and ash are the first and second predictors of DE and ME values of sorghum, respectively, and the tannin, EE, Trp, ash, CF, and ADF can be used as the key predictors for SID of CP and first four limiting AAs.

Fermentation of Whole Grain Sorghum (Sorghum bicolor (L.) Moench) with Different Dry Matter Concentrations: Effect on the Apparent Total Tract Digestibility of Energy, Crude Nutrients and Minerals in Growing Pigs

Simple Summary

Due to climate change and pests as result of maize monoculture, the need of diversification of crop rotation forces researchers to look for alternative grains for animal nutrition. Furthermore, grain fermentation may increase the nutritional value of feed and, simultaneously, decrease costs of feed conservation because the necessity for grain drying and associated energy costs are reduced. In this context, the cultivation and integration of early harvested and fermented sorghum grain in pig diets might be an interesting strategy for the substitution of maize. Therefore, we tested the nutritional value of three varieties of fermented sorghum grains with gradual differences in total dry matter, in a Latin-Square experiment comprising growing pigs. Results indicated there is a potential for improving the nutrient digestibility of sorghum-based pig diets by using early harvested and fermented whole sorghum grain with lower dry matter concentration. Especially the need for inorganic phosphorus supplementation and, hence, the fecal phosphorus emissions were significantly reduced.

Abstract

This study investigated the effects of sorghum ensiled as whole grains with different dry matter concentrations on the apparent total tract digestibility (ATTD) of energy, crude nutrients and minerals in growing pigs. Whole grain sorghum batches with varying dry matter (DM) concentrations of 701 (S1), 738 (S2) and 809 g kg⁻¹ (S3) due to different dates of harvest from the same arable plot, were stored in air-tight kegs (6 L) for 6 months to ensure complete fermentation. Subsequently, 9 crossbred barrows (34.6 ± 1.8 kg; (Duroc x Landrace) × Piétrain)) were used in a 3 × 3 Latin square feeding experiment. Diets were based on the respective sorghum grain silage and were supplemented with additional amino acids, minerals and vitamins to meet or exceed published feeding recommendations for growing pigs. The ATTD of gross energy, dry matter, organic matter, nitrogen-free extracts, and crude ash were higher in S1 compared to S3 treatments (p ≤ 0.05), while S2 was intermediate. Pigs fed S1 showed significantly higher ATTD of phosphorus (P) compared to all other groups while ATTD of calcium was unaffected irrespective of the feeding regime. In conclusion, growing pigs used whole grain sorghum fermented with a DM concentration of 701 g kg⁻¹ (S1) most efficiently. In particular, the addition of inorganic P could have been reduced by 0.39 g kg⁻¹ DM when using this silage compared to the variant with the highest DM value (809 g kg⁻¹).

Nutritional evaluation of different varieties of sorghum and the effects on nursery pig growth performance

Five experiments were conducted to determine the standardized total tract digestibility (STTD) of P, digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in three sorghum varieties compared with corn and to determine the effects of sorghum varieties on nursery pig growth. In exp. 1, 48 barrows (initially 18.6 kg) were housed individually in metabolism crates. Treatments were arranged in a 2 × 4 factorial evaluating two levels of microbial phytase (0 or 500 units/kg) and four grain sources (corn, high-lysine, red, or white sorghum). Added phytase improved (P < 0.05) STTD of P in all ingredients, but was not different among the grains. In exp. 2, the DE and ME in the three sorghum varieties were not different from corn. In exp. 3, 10 growing barrows (initially 25.9 kg) with a T-cannula in the terminal ileum were used. Standardized ileal digestible Lys, Met, Thr, and Val were greater (P < 0.05) in corn than in the sorghum-based diets with no differences among the sorghum varieties. In exp. 4, 160 pigs (initially 6.3 kg) were randomly allotted to one of four dietary treatments with five pigs per pen and eight replicate pens per treatment in a 20-d experiment. Dietary treatments included corn or the three sorghum varieties, where the varieties of sorghum replaced corn on an SID Lys basis. No differences among treatments were observed in any growth performance parameters. In exp. 5, treatments consisted of a corn-based diet, a diet based on conventional sorghum (a mixture of red and white sorghum), and four diets with high-lysine sorghum containing increasing amounts of feed-grade AA, replacing soybean meal. Overall, pigs fed the high-lysine sorghum diet with the greatest amount of added feed-grade AA had the poorest gain:feed ratio (G:F; P < 0.05) compared with pigs fed all the other experimental diets. Within those fed the high-lysine sorghum and feed-grade AA, average daily gain, final body weight (linear, P < 0.10), and G:F (linear, P < 0.01) decreased as feed-grade AA increased. In summary, no differences in STTD of P or in DE and ME were observed among the grain sources. The SID AA values for the three sorghum varieties were not different; however, they were all lower than for corn. These results indicate that these varieties of sorghum can successfully replace corn in nursery pig diets if diets are formulated to account for differences in AA digestibility.

Low-tannin white sorghum contains more digestible and metabolisable energy than high-tannin red sorghum if fed to growing pigs

The present study was conducted to determine and compare the digestible (DE) and metabolisable energy (ME) and the apparent total tract digestibility (ATTD) of gross energy (GE) in yellow-dent corn, three low-tannin white sorghum cultivars and three high-tannin red sorghum cultivars when fed to growing pigs. Forty-two barrows (34.8 ± 3.1 kg bodyweight) were housed in metabolic crates and allotted to one of seven diets with six pigs per diet in a completely randomised design. The seven diets were formulated to contain 969 g/kg of corn or one of the six sorghum cultivars as well as 31 g/kg vitamin and minerals. Faeces and urine were collected for 5 days following a 7-day adaptation period. The DE and ME were lower (P &lt; 0.05) for red sorghum than for corn while the values for corn were lower (P &lt; 0.05) than those obtained for white sorghum. The ATTD of GE for pigs fed corn was higher (P &lt; 0.05) than for pigs fed red sorghum but was lower (P &lt; 0.05) than the ATTD of GE for pigs fed white sorghum. Tannin had a high negative correlation with DE and ME (both, r = –0.99; P &lt; 0.01) and the ATTD of GE (r = –0.92; P &lt; 0.01). The DE, ME and ATTD of GE were positively correlated with CP (P &lt; 0.05), and negatively with kafirin/CP and phenols (P &lt; 0.05). However, tannin was negatively correlated with CP (r = –0.85; P &lt; 0.05), or positively with kafirin/CP (r = 0.88; P &lt; 0.01) and phenols (r = 0.77; P &lt; 0.05). Therefore, tannin content in sorghum may be the main anti-nutritional factor. The overall results of this study indicate that low-tannin white sorghum varieties are superior to high-tannin red sorghum varieties for use as an energy source in diets fed to growing pigs, and high-tannin red sorghum varieties should be incorporated into pig diets to ease the demand pressure on corn only if favourably priced in terms of their DE and ME values.

Impacts of energy feeds and supplemental protease on growth performance, nutrient digestibility, and gut health of pigs from 18 to 45 kg body weight

A total of 144 pigs with 18.4 ± 2.3 kg initial body weight (BW) at 6 wk of age were used in a 40-d trial to evaluate effects of protease (300,000 U/kg feed, BioResource International Inc., Durham, NC, USA) on growth performance, apparent ileal digestibility (AID) of nutrients, and gut health of pigs fed diets with sorghum. Pigs were randomly allotted to 4 treatments (12 pens per treatment, 3 pigs per pen) in a 2 × 2 factorial arrangement (corn or sorghum basal diets, and 0 or 0.05% protease as 2 factors) with sex and initial BW as blocks. Experimental period had phase 1 (d 1 to 21) and phase 2 (d 22 to 40). About 65% (phase 1) and 72% (phase 2) of cereal grains were used in corn or sorghum based diets. Both grains were ground to 400 μm. Body weight and feed intake were recorded weekly. On d 35, serum was collected to quantify tumor necrosis factor-α (TNF-α) and malondialdehyde (MDA). Titanium dioxide (0.3%) was added as an indigestible marker for an additional 4 d feeding. On d 40, 32 pigs (8 pigs per treatment) were euthanized to collect digesta from jejunum and ileum (for viscosity and AID), tissues (for morphology) and mucosa samples (for TNF-α and MDA) from duodenum, jejunum, and ileum. Replacing corn with sorghum in the diet increased (P < 0.05) overall average daily gain (from 756 to 787 g/day) and average daily feed intake (from 1,374 to 1,473 g/day), reduced (P < 0.05) overall gain:feed ratio (from 0.553 to 0.537), and did not affect AID. Pigs fed diets with sorghum had lower (P < 0.05) MDA content in serum (from 14.61 to 6.48 μmol/L) and jejunum (from 1.42 to 0.91 μmol/g protein), and reduced (P < 0.05) villus height (from 492 to 396 μm) and crypt depth (from 310 to 257 μm) in jejunum. Dietary protease improved (P < 0.05) AID of crude protein (from 81.8% to 86.0%), decreased MDA level (from 1.20 to 0.98 μmol/g protein) in duodenum, and increased (P < 0.05) the ratio of villus height to crypt depth (from 1.08 to 1.21) in duodenum. Overall, use of sorghum fully replacing corn in diets could benefit pigs with enhanced growth and feed intake potentially by reducing oxidative stress, whereas feed efficiency was compromised. Supplementation of protease improved protein digestion and maintained gut health, irrespective of sorghum or corn based diets.

Regression and direct methods do not give different estimates of digestible and metabolizable energy values of barley, sorghum, and wheat for pigs

Direct or indirect methods can be used to determine the DE and ME of feed ingredients for pigs. In situations when only the indirect approach is suitable, the regression method presents a robust indirect approach. Three experiments were conducted to compare the direct and regression methods for determining the DE and ME values of barley, sorghum, and wheat for pigs. In each experiment, 24 barrows with an average initial BW of 31, 32, and 33 kg were assigned to 4 diets in a randomized complete block design. The 4 diets consisted of 969 g barley, sorghum, or wheat/kg plus minerals and vitamins for the direct method; a corn-soybean meal reference diet (RD); the RD + 300 g barley, sorghum, or wheat/kg; and the RD + 600 g barley, sorghum, or wheat/kg. The 3 corn-soybean meal diets were used for the regression method. Each diet was fed to 6 barrows in individual metabolism crates for a 5-d acclimation followed by a 5-d period of total but separate collection of feces and urine in each experiment. Graded substitution of barley or wheat, but not sorghum, into the RD linearly reduced ( < 0.05) dietary DE and ME. The direct method-derived DE and ME for barley were 3,669 and 3,593 kcal/kg DM, respectively. The regressions of barley contribution to DE and ME in kilocalories against the quantity of barley DMI in kilograms generated 3,746 kcal DE/kg DM and 3,647 kcal ME/kg DM. The DE and ME for sorghum by the direct method were 4,097 and 4,042 kcal/kg DM, respectively; the corresponding regression-derived estimates were 4,145 and 4,066 kcal/kg DM. Using the direct method, energy values for wheat were 3,953 kcal DE/kg DM and 3,889 kcal ME/kg DM. The regressions of wheat contribution to DE and ME in kilocalories against the quantity of wheat DMI in kilograms generated 3,960 kcal DE/kg DM and 3,874 kcal ME/kg DM. The DE and ME of barley using the direct method were not different (0.3 < < 0.4) from those obtained using the regression method (3,669 vs. 3,746 and 3,593 vs. 3,647 kcal/kg DM, respectively). The direct method-derived DE and ME of sorghum were not different (0.5 < < 0.7) from those obtained using the regression method (4,097 vs. 4,145 and 4,042 vs. 4,066 kcal/kg DM, respectively). The direct method- and regression method-derived DE (3,953 and 3,960 kcal/kg DM, respectively) and ME (3,889 and 3,874 kcal/kg DM, respectively) of wheat were not different (0.8 < < 0.9). Results of these 3 experiments suggest that regression and direct methods do not give different estimates of DE and ME in barley, sorghum, and wheat for pigs.

Substituição parcial do milho por sorgo granífero na alimentação de matrizes suínas primíparas durante a lactação

Avaliou-se o efeito da substituição parcial do milho por sorgo granífero na dieta de matrizes suínas híbridas durante as fases de lactação e pós-desmame. Foram utilizadas 25 fêmeas, distribuídas em três tratamentos, com porcentagens crescentes de sorgo granífero - 0%, 25% e 50% - em substituição ao milho. Os animais foram avaliados durante as fases de lactação e pós-desmame, tendo sido mensurados o peso vivo (PV) e a espessura de toucinho (ET) ao parto, ao oitavo, 16º e 25º dias de lactação - desmame. Nesses momentos, foram realizadas colheitas de amostras de leite para análise bioquímica. As leitegadas foram pesadas no mesmo intervalo de tempo. No estro pós-desmame (RE), determinou-se o intervalo estro-cobertura (dias), PV e ET. Quanto às fêmeas, não ocorreram efeitos sobre o PV e a ET. Quanto ao número e ao peso dos leitões, as fêmeas do grupo controle apresentaram maior número de leitões nascidos vivos. O GPD dos leitões foi maior nas leitegadas dos tratamentos com 50% de sorgo. Não houve diferença para as análises do leite. No RE, não ocorreram efeitos. Dessa forma, conclui-se que o sorgo granífero pode substituir o milho em até 50% na dieta de fêmeas suínas durante lactação, sem comprometer os parâmetros produtivos e reprodutivos.

Substituição parcial do milho por sorgo granífero na alimentação de suínos nas fases de creche, crescimento e terminação

Avaliou-se o efeito da substituição parcial do milho por sorgo granífero na dieta de suínos castrados sobre as características de desempenho, carcaça e avaliação econômica. Foram utilizados 27 machos híbridos, oriundos de linhagem comercial, com 19,66 ± 2,92kg de peso inicial, distribuídos em três tratamentos com porcentagens crescentes de sorgo granífero - 0%, 25% e 50% - em substituição ao milho, em um delineamento inteiramente casualizado. Foram avaliados: ganho diário de peso, consumo diário de ração, conversão alimentar, espessura de toucinho e parâmetros bioquímicos sanguíneos - ureia, proteínas totais, creatinina, glicose, triglicerídeos e colesterol. Para as características de carcaça foram avaliados: peso nas carcaças quente e fria, rendimento nas carcaças quente e fria, pH e temperatura nas carcaças quente e fria e peso de cortes industriais. Para o desempenho econômico foi calculado o custo da ração, custo do kg suíno e índices de custo médio e de eficiência econômica. Foi utilizada análise de regressão para as variáveis produtivas. Não foram encontrados efeitos para o desempenho e características de carcaça. Nas variáveis bioquímicas, foram encontrados efeitos lineares para a ureia e proteínas totais, com os animais com 0% de sorgo apresentando os maiores valores. Quanto ao desempenho econômico, o grupo com 50% de sorgo apresentou o menor índice de custo e o maior de eficiência econômica. Dessa forma, conclui-se que a substituição do milho pelo sorgo granífero em níveis de até 50% da dieta representa uma alternativa sustentável na suinocultura regional.

Effects of substituting yellow corn for sorghum in geese diets on magret and foie gras quality

The aim of this trial was to study the effects of substitution of yellow corn with sorghum during the growing-finishing (G period), overfeeding (O period), or both periods on magret and foie gras quality in geese. In total, 260 ganders were divided into 4 groups (65 birds in each) differing in the cereal (yellow corn or sorghum) included in the diet given during the G and the O periods, using a 2 × 2 factorial arrangement of treatments. The groups differed in the nature of the cereal in the diet offered to birds between 44 and 104 d of age (G period: a diet containing 500 g of sorghum/kg (SS and SC groups) or a diet containing 500 g of yellow corn/kg (CS and CC groups). The groups differed also in the diet offered to birds between 105 and 120 d of age (O period): 967 g of yellow corn/kg (SC and CC groups) or 965 g of sorghum/kg (SS and CS groups). At the end of the O period, the birds were slaughtered after 10 h of fasting to measure foie gras and breast muscle weight, color, and chemical composition. The mortality in the SC group was higher (P < 0.05) than in the other 3 groups (14.29 vs. 3.58%, average of the 3 groups). After overfeeding, birds fed with sorghum had foie gras that were heavier 984 vs. 885 g, in CS+SS vs. CC+SC groups, respectively; P < 0.001) and less yellow (18.03 vs. 23.97 for b*, in CS+SS vs. CC+SC groups, respectively, P < 0.001) than birds fed with corn. The substitution of yellow corn with sorghum during the G and O periods (SS group) increased the weight of the foie gras, but altered its color to a paler yellow. In contrast, a substitution during the G period only (SC group) resulted in increased mortality during the O period.

Substituição parcial do milho por sorgo granífero na alimentação de matrizes suínas primíparas nos períodos de puberdade e gestação

Avaliou-se o efeito da substituição parcial do milho por sorgo granífero na dieta de matrizes suínas híbridas durante a puberdade e a gestação. Foram utilizadas 25 leitoas, distribuídas em três tratamentos com porcentagens crescentes de sorgo granífero - 0%, 25% e 50% - em substituição ao milho. As fêmeas foram avaliadas durante as fases de pré-puberdade, puberdade e gestação, tendo sido mensurados o peso vivo (PV) e a idade à puberdade nas jovens e o PV e a espessura de toucinho (ET) nas fêmeas gestantes - à cobrição e aos 30, 60, 90 e 110 dias de prenhez. Na fase de pré-puberdade, o ganho de peso diário diminuiu com o aumento da utilização do sorgo, e durante a puberdade não houve efeito dos tratamentos. Houve efeito linear da substituição sobre o PV aos 90 dias de gestação. Nos demais períodos, não foram encontrados efeitos significativos. Conclui-se que o sorgo granífero pode substituir o milho em até 50% na dieta de fêmeas suínas durante a puberdade e a gestação, sem comprometer as variáveis produtivas e reprodutivas.

The importance of dietary protein in human health: combating protein deficiency in sub-Saharan Africa through transgenic biofortified sorghum

Child malnutrition is increasing in Africa. Protein deficiency is an important cause since protein is essential for both growth and maintenance of muscle mass. Sorghum is a major staple food in Africa on account of its hardiness as a crop. However, sorghum protein is very deficient in the indispensable amino acid lysine and on cooking has poor protein digestibility. This results in sorghum having a very low Protein Digestibility Corrected Amino Acid Score (PDCAAS). The Africa Biofortified Sorghum project, a Grand Challenges in Global Heath project, is undertaking research to biofortify sorghum in terms of protein and micronutrient quality using genetic engineering. Lysine and protein digestibility have been improved by suppression of synthesis of the kafirin storage proteins. Transgenic biofortified sorghum has double the PDCAAS of conventional sorghum. This improvement should enable a young child to meet most of its protein and energy requirements from biofortified sorghum porridge. This together with the improvement in micronutrients could provide the basis of a sustainable and broadly comprehensive solution to child malnutrition in many African countries.