• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.1
• /
• pp.80-85
• /
• 2018

Objective: This study was conducted to investigate the effect of corn grain particle size on ruminant fermentation and blood metabolites in Holstein steers fed total mixed ration (TMR) as a basal diet to explain fundamental data of corn grain for cattle in Korea. Methods: Four ruminally cannulated Holstein steers (body weight $592{\pm}29.9kg$) fed TMR as a basal diet were housed individually in an auto temperature and humidity modulated chamber ($24^{\circ}C$ and 60% for 22 h/d). Treatments in a $4{\times}4$ Latin square design were TMR only (control), TMR with whole corn grain (WC), coarsely ground corn grain (CC), and finely ground corn grain (FC), respectively. The corn feeds substituted for 20% energy intake of TMR intake. To measure the ruminal pH, ammonia N, and volatile fatty acids (VFA), ruminal digesta was sampled through ruminal cannula at 1 h intervals after the morning feeding to determine ruminal fermentation characteristics. Blood was sampled via the jugular vein after the ruminal digesta sampling. Results: There was no difference in dry matter (DM) intake between different corn particle size because the DM intake was restricted to 1.66% of body weight. Different corn particle size did not change mean ammonia N and total VFA concentrations whereas lower (p<0.05) ruminal pH and a ratio of acetate to propionate, and higher (p<0.05) propionate concentration were noted when the steers consumed CC compared with WC and FC. Concentration of blood metabolites were not affected by different particle size of corn grain except for blood triglyceride concentration, which was significantly (p<0.05) increased by FC. Conclusion: Results indicate that feeding CC may increase feed digestion in the rumen, whereas the FC group seemed to obtain inadequate corn retention time for microbial degradation in the rumen.

• Animal Bioscience
• /
• v.34 no.9
• /
• pp.1491-1498
• /
• 2021

Objective: This research was carried out to investigate the effects of corn particle size on the apparent total tract digestibility (ATTD) of energy and nutrients fed to pigs at four different growth stages and therefore to provide basis for better application of corn in pig feeds. Methods: Eighteen weanling piglets, 18 growing barrows, 24 gestating sows and 24 lactating sows were used in this study. Within each stage, pigs were allotted to 1 of 3 or 4 corn-soybean meal diets which were formulated with different corn particle size in a completely randomized design with 6 replicate pigs per diet. Each stage lasted for 19 days, including 7 days for cages adaptation, 7 days for adaptation to diets and followed by 5 days for total collection of feces and urine. Results: For nursery and growing stages, the results showed that digestible energy content and ATTD of gross energy (GE), dry matter (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) was increased (p<0.05) as the corn particle size reduced. Meanwhile, the metabolizable energy content and ATTD of crude protein (CP) tended to increase. For gestating sows, no differences were found in the ATTD of nutrients among dietary treatments. As for lactating sows, there were linear and quadratic increases (p<0.05) in the ATTD of DM, GE, NDF as the corn being finer milled. Quadratic response in ATTD of ADF and CP (p<0.05) were observed as sows fed with four different diets. Conclusion: Reducing corn particle size can increase digestibility of nutrients fed to young pigs and lactating sows. No effects were observed in present experiment when gestating sows were fed with different particle sized corn.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.2
• /
• pp.286-293
• /
• 2020

Objective: Two experiments were conducted to evaluate the effects of corn particle size and lipid form on the apparent total tract digestibility (ATTD) of energy and nutrients in diets for growing pigs. Methods: In Exp. 1, thirty barrows (initial body weight [BW], 53.1±3.9 kg) were allotted to 1 of 5 diets formulated with 96.9% corn ground to 441, 543, 618, 659, and 768 ㎛, respectively. In Exp. 2, thirty-six barrows (initial BW, 54.7±3.6 kg) were allotted to 1 of 6 diets formulated by including 2% or 15% corn germ (CG 2 or CG 15), 1% or 6% corn oil (CO 1 or CO 6), 1% CO+2% corn germ meal (CO 1+CGM 2), or 6% CO+15% corn germ meal (CO 6+CGM 15), respectively. Results: The ATTD of gross energy (GE) and the digestible energy (DE) in diet and corn grain linearly decreased as the corn particle size increased (p<0.05) from 441 to 768 ㎛. Particle size had a quadratic effect (p<0.05) on the ATTD of neutral detergent fiber and acid detergent fiber in diets, and which firstly increased and then decreased as the corn particle size increased from 441 to 618 ㎛ and 618 to 768 ㎛, respectively. The ATTD of GE, ether extract (EE), and the DE in CO 1 diet and CO 6 diet was greater (p<0.05) than that in CG 2 diet and CG 15 diet, respectively. The ATTD of EE in CO 6 diet and CO 6+CGM 15 diet was greater (p<0.05) than that in CO 1 diet and CO 1+CGM 2 diet. Conclusion: Less than 618 ㎛ was recommended for corn particle size in growing pig's diet and extracted lipid had greater digestibility than the intact lipid in corn. Higher concentration of extracted CO had greater digestibility of EE compared with lower concentrations of CO diet.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.6
• /
• pp.872-877
• /
• 2002

Two experiments were conducted to determine the effects of reducing particle size of corn from 1,000 to 500 ${\mu}m$ in simple and complex diets for nursery pigs and broiler chicks. In Exp 1., 192 nursery pigs were used in a 24 d growth assay. Treatments were: 1) 1,000 ${\mu}m$ corn in a simple diet; 2) 500 ${\mu}m$ corn in a simple diet; 3) 1,000 ${\mu}m$ corn in a complex diet; and 4) 500 ${\mu}m$ corn in a complex diet. Overall, pigs fed complex diets had 9% greater ADG (p<0.005) and 5% greater gain/feed (p<0.01) compared to pigs fed simple diets. Also, pigs fed the 500 ${\mu}m$ treatments had 3% better overall gain/feed than those fed the 1,000 ${\mu}m$ treatments (p<0.007). At d 9, apparent digestibilities of DM, N and GE were greater for complex diets and diets with smaller particle size (p<0.02). At d 23, there were no differences in nutrient digestibility resulting from diet complexity, but pigs fed diets with corn ground to 500 ${\mu}m$ had greater digestibility of DM (p<0.02) and GE (p<0.003) than pigs fed diets with corn ground to 1,000 ${\mu}m$. A second experiment was designed to determine if four days old broiler chicks were an acceptable model for predicting the effects of feed processing procedures on nursery pigs. Chicks fed complex diets had 3% greater gain/feed than chicks fed simple diets (p<0.001). Rate of gain and feed intake were improved by 3 and 2%, respectively, for chicks fed crumbled diets (p<0.03). However, there were several significant interactions among the main effects. For instance, crumbling did not affect gain/feed in chicks fed complex diets, but rate of gain and feed intake were increased by 7 and 6%, respectively, when simple diets were crumbled (diet complexity${\times}$diet form, p<0.001). Also, gain/feed of chicks was improved by 3% when particle size was reduced in meal diets, but not affected in chicks fed crumbles (diet form${\times}$particle size, p<0.005). Thus, our data suggested that reduction of particle size of corn was important for simple and complex diets and that a complex diet with 1,000 ${\mu}m$ corn gave no better performance than a simple diet with 500 ${\mu}m$ corn.

• Journal of Animal Science and Technology
• /
• v.63 no.5
• /
• pp.1018-1033
• /
• 2021

In this study, we aimed to assess the effect of flaking on the nutrient digestibility of corn grain in ruminants. In this regard, in vitro rumen fermentation, in situ rumen degradability, and in vivo metabolic experiments were performed. The automated gas production technique was used for the in vitro fermentation experiments. Six types of corn flakes with various degrees of gelatinization (32%, 41%, 48%, 66%, 86%, and 89%) were ground and incubated in rumen fluid to measure rumen fermentation characteristics and digestion rate. The in situ degradability of ground corn, whole corn, and corn flakes with 62% and 66% gelatinization was measured by incubation in the rumen of two cannulated Holstein cows. In vivo metabolic experiments were performed using 12 crossbred goats (29.8 ± 4.37 kg) using a 3 × 3 Latin square design. The dietary treatments consisted of ground corn and flaked corn with 48% or 62% gelatinization. In vitro experiments showed that as the degree of gelatinization increased, the digestion rate increased linearly, while the discrete lag time decreased linearly (p < 0.05). The effective rumen dry matter degradability, determined by in situ fermentation, was 37%p lower in corn flakes than ground corn, assuming a passage rate of 6%/h (p < 0.01), and there was no difference between the two flakes. In the in vivo experiment, there was no difference in dry matter intake, average daily gain, feed efficiency, and nitrogen utilization among the treatment groups (p > 0.05); however, the crude fat digestibility was lower for corn flakes than for ground corn (p < 0.05). To summarize, the rate of fermentation of corn flakes increased as the degree of gelatinization increased. However, non-ground corn flakes had lower rumen digestibility and did not improve in vivo apparent nutrient digestibility, compared with ground corn. In contrast to the assumption that flaked corn provides more energy to ruminant animals than ground corn, we conclude that the digestibility and energy value of corn flakes are lower than those of ground corn if mastication does not sufficiently reduce the particle size of corn flakes.

• Microbiology and Biotechnology Letters
• /
• v.18 no.4
• /
• pp.352-359
• /
• 1990

The synergistic effect of glucoamylase and a -amylase on the hydrolysis of raw corn starch in an agitated bead reaction system was studied by investigating the changes of sugar profiles, the granular structure, particle size distribution, and X-ray diffraction pattern of residual raw corn starch. The enzymatic hydrolysis of raw corn starch was greatly enhanced by synergistic effect of glucoamylase and $\alpha$ -amylase. Even though the sugar profiles were mainly determined by the mixing ratio of glucoamylase and $\alpha$-amylase; raw starch was mainly converted to glucose directly without accumulation of any significant amount of oligosaccharides. The cavity formation and fragmentation phenomena of raw corn starch granule subjected to enzyme reaction were analyzed by means of SEM and the particle size distribution. The X-ray diffraction pattern of raw starch was not changed at the initial stage of reaction but slightly changed at the late stage of hydrolysis, which may be caused by the preferential degradation of amorphous region by enzymatic reaction, not by the destruction of microcrystalline structure of raw corn starch.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.5
• /
• pp.708-712
• /
• 2002

Effects of unprocessed (whole) or steam-flaked corn with or without enzyme additives on in vivo nutrient digestibilities and distribution of corn particles in the feces of Holstein steers were determined in a $4{\times}4$ Latin square experiment using four Holstein steers fed the diets containing 1) whole corn without enzyme additive, 2) whole corn with enzyme additive, 3) flaked corn without enzyme additive, or 4) flaked corn with enzyme additive. With regard to nutrient digestibilities such as DM, CP, CF, NFE, NDF, and ADF, no significant differences were detected among treatments, and also the nutrient digestibilities were not affected by the addition of enzyme additive. When distribution of corn particles in the feces was examined, there were no significant differences in the amount of 2, 8 mm and total corn particles. However, feeding flaked corn resulted in less corn particles (4 mm) in the feces than feeding whole corn (p<0.05). There were no significant differences in amounts of corn particles in the feces due to the addition of enzyme additive.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.57 no.1
• /
• pp.41-50
• /
• 2012

The study was carried out to analyze the relationship between analysis of antioxidant activity and the level of functional components according to particle size of corn silk. Particle size was classified into 5 groups. By particle size distribution and color difference, the total phenol content and DPPH radical scavenging activity were observed. The particle sizes of corn silk were $199.17{\mu}m$, $178.27{\mu}m$, $85.48{\mu}m$, $27.4{\mu}m$ and $20.97{\mu}m$, respectively. The lightness of colored pigments was increased when the particle size was decreased. The contents of free sugar (fructose, glucose, galactose, sucrose, and maltose) of corn silk were analyzed using a HPLC. The total phenol contents by the particle sizes of corn silk were 2.01 mg/g, 2.02 mg/g, 2.06 mg/g, 2.26 mg/g and 2.26 mg/g, respectively. DPPH radical scavenging activities of samples were 21.00%, 21.75%, 22.90%, 24.35% and 23.67%, respectively. Antioxidative activities of Trolox and Fe(II) in corn silk were measured by ferric reducing antioxidant power (FRAP) assay and Trolox equivalent antioxidant capacity (TEAC) assay. TEAC values of samples were $2.36{\mu}mol$ TE / g dw, $2.81{\mu}mol$ TE / g dw, $3.20{\mu}mol$ TE / g dw, $3.36{\mu}mol$ TE / g dw, and $3.44{\mu}mol$ TE / g dw, respectively. FRAP values of samples were $11.67{\mu}mol$ Fe(II) / g dw, $12.80{\mu}mol$ Fe(II) / g dw, $13.43{\mu}mol$ Fe(II) / g dw, $13.85{\mu}mol$ Fe(II) / g dw and $15.95{\mu}mol$ Fe(II) / g dw, respectively. Total phenolic content and antioxidantive activities based on FRAP assay and TEAC assay were increased with decreasing particle size. In addition, DPPH radical scavenging activity was also increased. A significant correlation was also noted between DPPH radical scavenging activities and the content of phenolic compounds.

• Journal of Nutrition and Health
• /
• v.25 no.6
• /
• pp.450-460
• /
• 1992

The study was performed to investigate the effect of corn bran as a fiber source on the utilization of thiamin niacin and pantothenic acid in human subjects for 8 weeks. Four different corn bran diets were fed : dry milled fine(DF) dry milled coarse(DC) wet milled fine(WF) and wet milled coarse(WC) Basal diet no corn bran bread added was employed as a control Apparent recovery of each B complex vitamin in urine was estimated to evaluate the vitamin and compared. The utilziation of three B vitamins was affected by the corn bran treatment. Dry milled corn bran had a higher recovery rate of thiamin(dry milled : 233% wet milled : 1.70%) than those receiving wet milled corn bran. Similar recovery pattern of niacin(dry milled : 1.94% wet milled : 1.50%) to that of thiamin was also observed. Particle size seemed to affect the vitamin utilization regardless of type of corn bran. Coarse bran gave a lower recovery value than fine corn bran in genreral. For pantothenic acid the recovery of the vitamin was affected to a greater extent by particle size of corn bran than by type of corn bran milling(fine: 60.22% coarse : 51.51%) Groups consuming wet milled corn bran\ulcorner(5`.57%) excreted more NDF than those fed dry milled corn bran(42.29%) Dry milled corn bran showed little or no water holding capacity poor fecal bulking properties and increased fecal transit time. The results suggest that corn bran supplementation exerts an negative effect on three B vitamin utilization.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.12
• /
• pp.1749-1754
• /
• 2006

Two slaughter experiments were conducted to determine the effects of rumen escape starch, by altering dietary starch concentration and corn particle size, on ${\alpha}$-amylase activity in the pancreas and the small intestinal digesta of lambs. In experiment 1, 18 wether lambs (28.5${\pm}$1.6 kg) were fed low, medium or high starch diets for 35 d and slaughtered. Dietary starch concentrations linearly increased rumen escape starch (p<0.05). Pancreatic ${\alpha}$-amylase activity was lower (p<0.05) in lambs fed the low starch diet. When expressed per gram of digesta, ${\alpha}$-amylase activity was lower in lambs fed the low starch diet. However, expressed as total activity, ${\alpha}$-amylase in the digesta was greater in lambs fed the medium starch diet. In experiment 2, 12 wether lambs (23.5${\pm}$0.3 kg) were fed diets with finely cracked corn, coarsely cracked corn and whole corn. These dietary treatments continued for 35 d before tissue collection. Rumen escape starch increased with increasing corn particle size (p<0.05). ${\alpha}$-amylase activity in the pancreas and the small intestinal digesta was significantly greater (p<0.05) in lambs fed the coarsely cracked corn. These data suggest that increasing rumen escape starch results in a quadratic increase in total ${\alpha}$-amylase activity in the pancreas and the small intestinal digesta. Maximum ${\alpha}$-amylase activity is reached when rumen escape starch is about 100-120 g/d in 25-30 kg lambs.