J. Anim Sci.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J. Anim Sci. 2006. 84:2779-2786. doi:10.2527/jas.2005-353
© 2006 American Society of Animal Science
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Opapeju, F. O.
Right arrow Articles by Sapirstein, H. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Opapeju, F. O.
Right arrow Articles by Sapirstein, H. D.

ANIMAL NUTRITION

Growth performance and carcass characteristics of pigs fed short-season corn hybrids1

F. O. Opapeju*, C. M. Nyachoti*,2, J. D. House*,{dagger}, H. Weiler{dagger} and H. D. Sapirstein{ddagger}

* Departments of Animal Science, and {dagger} Human Nutritional Sciences, and and {ddagger} Food Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2


   Abstract
Top
 Abstract
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 LITERATURE CITED
 
An experiment was conducted to determine growth performance, carcass characteristics, and fat quality of growing-finishing pigs fed diets based on short-season corn hybrids. Twenty-four individually housed, Cotswold, growing pigs with an initial BW of 41.4 (SD = 1.4) kg were blocked by BW and sex and randomly allotted from within block to 1 of 3 diets to give 8 replicate pigs per diet. Experimental diets consisted of a control based on barley and 2 diets based on corn as the main energy sources. A 3-phase feeding program for 20 to 50 kg (phase I), 50 to 80 kg (phase II), and 80 to 110 kg (phase III) of BW was used. Diets for each phase contained approximately 3.5 Mcal/kg of DE, with total lysine of 0.95, 0.75, and 0.64% in phase I, II, and III diets, respectively. Average daily gain, ADFI, and G:F were monitored weekly during each phase. Pigs were slaughtered after reaching a minimum BW of 100 kg to determine carcass characteristics. There were no effects of diet on ADG, ADFI, and G:F (0.45 ± 0.02, 0.34 ± 0.02, and 0.31 ± 0.02 for phase I, II, and III, respectively). Carcass length, dressing percent, LM area, loin depth, backfat thickness, belly firmness, and L*, b*, and a* fat color were not different across dietary treatments. Pigs fed one corn variety had no differences in fatty acid profile with barley-fed pigs, whereas those fed the other variety of corn had a greater (P < 0.05) concentration of PUFA in their backfat. The results indicate that growth performance, carcass characteristics, and fat quality of pigs fed diets based on short-season corn hybrids and those fed the barley-based diet were not different.

Key Words: carcass quality • corn • growth performance • pig


   INTRODUCTION
Top
 Abstract
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 LITERATURE CITED
 
Traditionally, corn production in Manitoba, Canada, has been low because of the climate; however, it has increased recently due to the development of high yielding, low-corn heat units (CHU) rated hybrids by plant breeders. In areas with low temperatures, such as Manitoba, the heat available to support corn growth is measured by CHU, a quantitative assessment of the useful heat available for the growth and development of corn (MAFRI, 2004Go).

Because of the increase in corn production, the amount of locally grown corn that is available for use in making swine feed has increased. However, pigs fed corn-based diets could produce inferior quality products for some markets compared with pigs fed barley- or wheat-based diets in terms of meat and fat color because yellow corn contains higher amounts of carotenoids, naturally occurring fat soluble pigments often found in plants (NRC, 1998Go; Prache et al., 2003Go; Carr et al., 2005Go).

Another product quality concern related to feeding corn-based diets to pigs is the production of soft fats due to the high content of unsaturated fatty acids (UFA) in corn. A high amount of UFA in pork has been associated with increased difficulties in belly slicing and such quality problem as susceptibility to rapid oxidative rancidity (Averette Gatlin et al., 2002Go). According to Carr et al. (2005)Go, pigs fed a corn-based diet had higher G:F than those fed a barley-based diet but similar carcass characteristics. However, Robertson et al. (1999)Go reported that pigs fed corn-based diets had darker LM compared with those fed diets based on hulless barley. Thus, the effects of feeding corn vs. barley to swine on growth performance and carcass characteristics have not been conclusively determined.

Therefore, the objective of this study was to evaluate the effects of representative Manitoba-grown corn hybrids on growth performance and carcass characteristics of growing-finishing pigs using a barley-based diet as control.


   MATERIALS AND METHODS
Top
 Abstract
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS AND DISCUSSION
 LITERATURE CITED
 
Animals and Diets

The use of pigs and the experimental procedures were reviewed and approved by the Animal Care Committee of the University of Manitoba, and animals were cared for according to the standard guidelines of the Canadian Council on Animal Care (CCAC, 1993Go).

Twenty-four Cotswold pigs (12 barrows and 12 gilts) with an average initial BW of 41.4 (SD = 1.4) kg were obtained from the University of Manitoba’s Glenlea Swine Research Farm for use in this study. Pigs were blocked on the basis of BW and sex into 8 blocks (4 blocks each of barrows and gilts) each with 3 pigs. Pigs from each block were randomly allotted to 1 of 3 treatment groups, resulting in a total of 8 pigs per treatment. The 3 dietary treatments consisted of a barley-based diet (control) and 2 diets each based on 1 of the 2 most cultivated corn hybrids in Manitoba, 39M27 (Pioneer Hi-Bred Ltd, Chatham, ON; corn 1) and 39W54 (Pioneer Hi-Bred Ltd, Chatham, ON; corn 2).

The barley sample is a 6-row barley hybrid and the corn hybrids are early maturing hybrids requiring less than 2,400 CHU, an equivalent of less than 75 d, to reach maturity (Dwyer et al., 1991Go). The CHU rating of corn 1 and corn 2 were 2,150 and 2,100, respectively. Corn 1 is a genetically modified corn that is resistant to European corn borer. It contains a protein (Cry 3Bbl) from a bacterium, Bacillus thuringiensis, that is toxic to European corn borer and thus could potentially minimize the use of insecticides (MAFRI, 2004Go; Hyun et al., 2005Go). All grain samples were from the 2003 planting season harvest. The 2 corn samples were obtained from Carman, Manitoba, whereas the barley sample was obtained from the University of Manitoba Glenlea Research Station. The 2 locations were within 100 km of Winnipeg (49°53' N, 97°10' W), Canada.

The pigs were fed on a 3-phase dietary program for BW 20 to 50 kg (phase I), 50 to 80 kg (phase II), and 80 to 110 kg (phase III). Diets for each phase were formulated to meet the NRC (1998)Go nutrient standards for mixed sexes, with a high to medium lean growth rate (Table 1Go). The analyzed lysine (0.26 and 0.24% for corn 1 and corn 2, respectively) and other AA contents of the corn samples were similar to NRC (1998)Go values (Opapeju, 2005Go). Hence, the diets were formulated using NRC (1998)Go values based on the total lysine content of the ingredients, and the calculated dietary levels of CP, total lysine, and DE were similar across dietary treatments within each phase.


View this table:
[in this window]
[in a new window]
  		Table 1. Ingredient composition (as-fed basis) and calculated nutrient composition of the experimental diets
 
Pigs were housed individually in 1.83 x 1.22-m floor pens with plastic-covered, expanded metal, sheet flooring in a temperature controlled room (19 to 21°C). Each pen was equipped with a feeder and a nipple drinker to allow unrestricted access to feed and water at all times. The diets were provided in mash form. Individual pig BW and feed disappearance were monitored weekly during each phase to determine ADG, ADFI, and G:F.

Carcass Evaluation

On reaching an average live BW of 107.8 (SD = 2.9) kg, pigs were slaughtered after 18 h of feed deprivation. Before slaughter, pigs were weighed and then given an intramuscular injection of acepromazine maleate (0.3 mg/kg of BW; Atravet 10 mg injectable, Wyeth Animal Health, Ontario, Canada) mixed in a single syringe with 15 mg of ketamine hydrochloride/kg of BW (Ketalean, Bimeda-MTC Animal Health Inc., Ontario, Canada) as a preanesthetic tranquilizer. Once tranquilized sufficiently, approximately 20 mg of sodium pentobarbital/ kg of BW (Bimeda-MTC Animal Health Inc.) was administered intravenously through the lateral ear vein to provide for a plane of surgical anesthesia but not enough to cause respiratory arrest. Pigs were then exsanguinated, and the viscera were removed. The dressing percent was determined as the ratio of HCW (head-on) to live BW at slaughter. The carcasses (head-on) were then split in 2 by cutting through the backbone and stored in a cooler at 4°C.

After 24 h in the cooler, carcass length was measured on the right half of the carcass as the distance between the cranial face of the first rib and the tip of the aitch bone. The belly was fabricated from the right half of the carcass according to the UN/ECE standard procedure for porcine carcasses and cuts (ECE, 1997Go). Approximately 36 x 48 cm of the belly was removed and subjected to the belly flex test described by Rentfrow et al. (2003)Go. Briefly, the carcass was centered on a polyvinyl chloride pipe (9-cm diam.) mounted perpendicularly on a board marked with a 2.54-cm grid matrix with the skin side down and the chine side against the board. Lateral and vertical flexes were calculated as the average of the lateral and vertical left and right flexes determined relative to the grid matrix on the left and right side of the board, respectively. About 50 g of leaf fat was removed for belly fat fatty acid analysis.

The left half of the carcass was evaluated for backfat thickness, loin depth, and LM area (LMA). Midline backfat thickness was measured perpendicular to the skin at the first and last rib and at the last lumbar vertebra. The carcass was cut using the Hobart meat-cutting machine (The Hobart Mfg. Co., Ltd., Toronto, Canada) between the 10th and 11th ribs to determine the 10th rib fat thickness, LM depth, and LMA. The outline of the LM was traced on acetate paper, and the LMA was later determined using a 0.25-cm2 grid. Samples of subcutaneous fat were obtained from each pig at the 10th and 11th ribs for backfat fatty acid and fat color analysis, respectively. The samples, about 50 g for fatty acid analysis and approximately 8 x 10 cm for fat color analysis, were carefully separated from the attached muscle. All fat samples were rinsed with saline solution (0.9%) and stored at –80°C until further analysis.

Fat color was evaluated according to the Commission International de l’Eclairage (CIE) L* (lightness), a* (red-green scale), and b* (yellow-blue scale) values (CIE, 1976Go) using a Minolta Spectrophotometer CM-3500d (Minolta Co., Ltd., Osaka, Japan). The spectrophotometer was calibrated using the manufacturer’s zero calibration and white, standard, calibration caps. The L* scale ranged from 0 to 100%; that is, the greater the value, the lighter the color; the a* scale ranged from negative (green) to positive (red); and the b* scale ranged from negative (blue) to positive (yellow). Each sample was read thrice.

Fatty Acid Analysis

Feed ingredient samples (corn and barley) and belly fat and backfat samples were analyzed for fatty acids. A representative sample of each grain ground through a 1-mm screen and thoroughly mixed was subjected to lipid extraction according to AOAC (1990)Go procedures. Extracted oil was methylated following the procedure of Folch et al. (1957)Go. Belly fat and backfat samples were extracted and methylated according to the procedures of Folch et al. (1957)Go.

Fatty acid methyl esters were analyzed using a Hewlett-Packard 5890A gas chromatograph equipped with an autosampling injection system HP 7673 (Hewlett-Packard Inc., Avondale, AZ). The 100-m-long column, an Agilent HP-88 capillary column (J and W Scientific, Folsom, CA), was made of fused silica coated with 88% cyanopropyl aryl siloxane (0.25-mm i.d. and 0.2-µm film thickness). The column temperature began at 50°C, and after 1 min, it increased at a rate of 20°C/min to 160°C and was held at this level for 23 min. The temperature then increased at a rate of 2°C/min to 210°C and was held there for 7 min. To clean the column between samples, the column temperature was increased at a rate of 20°C/min to 240°C and was held at this level for 5 min. The flame ionization detector temperature was kept constant at 300°C. The fatty acid methyl esters were identified using a methyl ester standard GLC-461 (Nu Check Prep Inc., Elysian, MN).

Statistical Analysis

All data were subjected to ANOVA with a randomized complete block design using the GLM procedures of SAS (SAS Inst. Inc., Cary, NC). The effects of sex (df = 1), block within sex (df = 6), and dietary treatment (df = 2) were included in the model as sources of variation. The individual pig was considered as the experimental unit. When a significant F-value (P < 0.05) was indicated by the ANOVA, dietary treatment means were separated and compared using Tukey’s test.


   RESULTS AND DISCUSSION
Top
 Abstract
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
LITERATURE CITED
 
The fatty acid profile of barley and the 2 corn hybrids is presented in Table 2Go. Barley had a higher amount of SFA compared with the 2 corn hybrids, with the amount of myristic acid (14:0), palmitic acid (16:0), and arachidic acid (20:0) in barley being at least 367, 50, and 306%, respectively, higher than in the 2 corn hybrids. However, the 2 corn hybrids had higher amounts of oleic acid (18:1) compared with barley. This observation is consistent with previous research showing that corn has a higher amount of UFA compared with barley (NRC, 1998Go; Carr et al., 2005Go). The fatty acid profiles of the 2 corn hybrids varied (Table 2Go), which further confirms reports of variability in the chemical and nutrient composition of corn or corn products (Sproule et al., 1988Go; Adeola and Bajjalieh, 1997Go; Moeser et al., 2002Go). The fatty acid profiles of the corn hybrids evaluated in the current study were similar to the values reported by Rentfrow et al. (2003)Go. Compared with the report of Carr et al. (2005)Go, corn and barley samples evaluated in this study were at least 39, 65, and 123% lower in palmitic acid (16:0), palmitoleic acid (16:1), and stearic acid (18:0) concentration but about 20% higher in linoleic acid (18:2) concentration. In the barley and corn samples evaluated in the current study, palmitic acid and linoleic acid constituted the highest proportion of SFA and UFA, respectively (Table 2Go), and this observation is consistent with the reports of Rentfrow et al. (2003)Go and Carr et al. (2005)Go. The evaluated cereals contributed the bulk of dietary fat representing 86, 83, and 84% of diet based on barley, corn 1, and corn 2, respectively (Table 3Go). The pattern observed for dietary fatty acid profile (Table 3Go) was similar to that of the cereal component of the diet (Table 2Go). For example, barley-based diet had more myristic and arachidic acid but less stearic and oleic acid compared with corn-based diets just as observed in the cereals.


View this table:
[in this window]
[in a new window]
  		Table 2. Fatty acid profiles (% of total) in barley and the corn cultivars used in the experimental diets1,2
 

View this table:
[in this window]
[in a new window]
  		Table 3. Fat content (%) and fatty acid profile (% of the diet) of phase III diets1
 
A pig was lost during the experiment due to a non-treatment-related event. In the current study, sex results are presented only for the response criteria where the sex effect was significant because sex was only used for blocking and not as a primary question of the study. As a result, the experimental diets were formulated to meet the nutrient requirement for specific phases of pig’s growth and not for the differing nutrient requirements of the sexes. The effects of sex, where observed, were consistent with other studies. Interactions between diets and sex were not observed other than random occurrence with no biological implications.

Growth Performance and Carcass Characteristics

The effects of dietary treatment on ADG, ADFI, and G:F are presented in Table 4Go. There were no differences in ADG, ADFI, and G:F of pigs fed the barley-based diets compared with those fed diets based on either of the 2 corn hybrids during any phase of the study or overall. Similarly, Carr et al. (2005)Go did not detect any differences in ADG, ADFI, and G:F between pigs (45 to 80 kg of BW) fed a barley-based diet and those fed a corn-based diet.


View this table:
[in this window]
[in a new window]
  		Table 4. Effects of diet (barley vs. corn) on growth performance of growing-finishing pigs1
 
Carcass characteristics of pigs fed barley- and corn-based diets are shown in Table 5Go. There were no differences in dressing percent, carcass length, backfat thickness, loin depth, and LMA among dietary treatments, which is consistent with the findings of Carr et al. (2005)Go showing no differences in the carcass and fat characteristics of pigs fed corn- and barley-based diets. Likewise, as in this study, Hyun et al. (2004Go, 2005)Go did not find any differences in the carcass characteristics of pigs that were fed diets based on different hybrids of corn.


View this table:
[in this window]
[in a new window]
  		Table 5. Effects of diet (barley vs. corn) on carcass characteristics of growing-finishing pigs1
 
The belly firmness as measured with the belly flex test was not affected by dietary treatment (Table 5Go). The values observed for the belly flex test for pigs that received corn 1 and 2 were similar to the values, 18 and 13 cm for vertical and lateral flex, respectively, reported by Rentfrow et al. (2003)Go for a similar size of belly for pigs fed conventional corn-based diets. The belly flex of pigs fed the barley-based diet was similar to that of pigs fed the corn-based diets, although this could not be compared with previous research because this approach has not previously been used to measure belly firmness in pigs fed barley-based diets.

There was no effect of dietary treatment on the L*, a*, and b* fat color (Table 5Go). Similar to the result of the current study, Carr et al. (2005)Go did not find any differences in L*, a*, and b* fat color of pigs fed the diet based on barley compared with those fed the corn-based diet. Corn has higher amount of pigments compared with barley (NRC, 1998Go), and this could contribute to the deposition of color fat (Carr et al. 2005Go). Although we did not measure carotenoid concentration of the grain samples used in the current study, differences in the concentration of pigments between corn and barley, if there were any, did not affect pork fat color.

Fatty Acid Profiles of the Backfat and Belly Fat

The effects of dietary treatment on the profile of fatty acid in backfat are presented in Table 6Go. The backfat of pigs on the barley-based diet tended to have higher concentration of pentadecanoic acid (15:0; P = 0.092), palmitoleic acid (16:1; P = 0.080), and heptadecanoic acid (17:0; P = 0.089) compared with those fed the diet based on corn 2. Pigs on the barley-based diet had a higher (P < 0.05) concentration of heptadecenoic acid (17:1; P = 0.006) in their backfat compared with those that received diets based on corn. The concentration of eicosenoic acid (20:1) in the backfat of pigs fed diets based on barley and corn 1 was higher (P < 0.05) compared with those fed diet based on corn 2. The backfat of pigs fed the diet based on corn 2 had higher (P < 0.05) concentrations of linoleic acid (18:2) and PUFA compared with pigs fed the diet based on barley. Linoleic acid (18:2) is the only PUFA that was significantly (P = 0.038) affected by dietary treatment, and it is prob ably the component responsible for the dietary differences observed in the concentration of PUFA in the backfat of the pigs. Others have reported a positive correlation between linoleic acid (18:2) and PUFA in pork fat (Averette Gatlin et al., 2002Go; Rentfrow et al., 2003Go). Despite the fact that the backfat from pigs fed the diet based on corn 2 had a higher concentration of PUFA compared with those fed the diet based on barley, the concentration of PUFA in the backfat of all pigs regardless of dietary treatment was within the range (less than 23%) recommended for salami making (Warnants et al., 1998Go). The fatty acid profiles of backfat of pigs fed the barley- and corn-based diets in the current study are similar to the values reported by Carr et al. (2005)Go for these feedstuffs. The differences in the fatty acid composition of barley and the 2 corn hybrids used in the current study did not affect the deposition of SFA and UFA in the backfat of pigs. The concentration of SFA and UFA in the backfat was not different across dietary treatments.


View this table:
[in this window]
[in a new window]
  		Table 6. Effect of diet (barley vs. corn) on backfat fatty acid profiles (% of total) in finishing pigs1,2
 
Pigs fed the barley-based diet had a lower (P = 0.004) concentration of eicosatrienoic acid (20:3) in the belly fat compared with those fed the diet based on corn 2 (Table 7Go). The concentration of heptadecanoic acid (17:0) and heptadecenoic acid (17:1) were higher (P < 0.05) in the pigs fed the barley-based diet compared with those fed either diets based on corn. Pigs fed the barley-based diet tended to have higher concentration of pentadecanoic acid (15:0; P = 0.088), palmitic acid (16:0; P = 0.059), SFA (P = 0.073), and SFA:UFA ratio (P = 0.076) but lower concentration of oleic acid (18:1; P = 0.077), linoleic acid (P = 0.054), PUFA (P = 0.052), and UFA (P = 0.077) in their belly fat compared with those fed the diet based on corn 2. However, the concentrations of linoleic acid and PUFA in the belly fat of pigs across all dietary treatments were within the recommended range of less than 14 and 15%, respectively, required for quality bacon processing (NPPC, 2000Go). This observation is in agreement with the belly flex results showing no differences in the belly firmness across dietary treatments. Furthermore, the concentration of linoleic acid in the backfat and belly fat among dietary treatments was within the accepted value of less than 30%; above this value, oxidative rancidity becomes a serious problem (Houben and Krol, 1980Go). From these results, the variability in fatty acid composition of the corn cultivars evaluated in this study (Table 2Go) had no effect on fat firmness as both hybrids supported similar deposition of fatty acids into the belly fat and backfat of pigs.


View this table:
[in this window]
[in a new window]
  		Table 7. Effect of diet (barley vs. corn) on belly fat fatty acid profiles (% of total) in finishing pigs1,2
 
Contrary to the observed pattern of fatty acid deposition in the backfat of barrows and gilts, the belly fat of barrows had a higher (P < 0.05) concentration (%) of capric acid (0.11 vs. 0.09) and pentadecanoic acid (0.05 vs. 0.04) but lower concentration of linolenic acid (0.23 vs. 0.28) compared with that of gilts. Barrows tended (P = 0.068) to have higher palmitic acid (29.56 vs. 27.12%) but lower (P = 0.079) MUFA (35.66 vs. 39.13%) in belly fat. However, there were no sex differences in the concentration of SFA, PUFA, UFA, and SFA:UFA ratio in the belly fat averaging 51, 12, 49, and 1%, respectively. The observed difference in the bellyfat fatty acid profiles of barrows and gilts is consistent with previous studies. For example, Warnants et al. (1999)Go reported higher (P < 0.01) concentration of palmitic acid (16:0) and SFA but lower (P < 0.01) concentration of eicosenoic acid (20:1), eicosadienoic acid (20:2), and eicosatetraenoic acid (20:4) in the backfat of barrows compared with that of gilts. Likewise, Piedrafita et al. (2001)Go reported that gilts had a higher (P < 0.01) concentration of linoleic acid (18:2), linolenic acid (18:3), and UFA but a lower (P < 0.01) concentration of stearic acid (18:0) in their backfat compared with barrows. From the results of the current and previous studies, it is evident that gilts tend to deposit more UFA compared with barrows.

There was a treatment x sex interaction (P < 0.05) on lauric acid (12:0) and oleic acid (18:1) contents of the belly fat. Although there was no difference in the lauric acid concentration in the belly fat of gilts and barrows receiving the diets based on barley and corn 1, the barrows fed the diet based on corn 2 had a higher (P = 0.018) value compared with the gilts (0.11 vs. 0.09%). Similarly, the gilts fed the diet based on corn 2 had a higher (P = 0.035) concentration of oleic acid (36.23 vs. 31.29%) in their belly fat compared with the barrows, but the concentration was not different for the gilts and barrows on the barley and corn 1 diets.

Recently developed hybrids of corn grown in Manitoba are specifically bred for lower CHU, hence the need to know how low CHU influence the nutrient profile of corn and eventually growth performance and carcass characteristics. It is obvious in this study there were no differences in growth performance and carcass quality of growing-finishing pigs fed diets based on the low-CHU-rated hybrids of corn that are available in Manitoba and those fed the barley-based diet. Likewise, there was no difference in the feeding value of corn 1 (B. thuringiensis corn) and that of corn 2. Assuming a relatively similar feed intake in ad libitum-fed pigs in a commercial setting, body fatty acid composition should not be a concern when these corn hybrids are used instead of barley in swine diets as long as the diets are formulated to meet lysine:energy requirements of the growing-finishing pigs.


   Footnotes
 
1 We appreciate Manitoba Corn Growers Association and Manitoba Pork Council for financial support. Special thanks to G. H. Crow and L. Onischuk for helping with statistical analysis. Back

2 Corresponding author: martin_nyachoti{at}umanitoba.ca

Received for publication July 3, 2005. Accepted for publication June 1, 2006.


   LITERATURE CITED
Top
 Abstract
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 LITERATURE CITED
 


Adeola, O., and N. L. Bajjalieh. 1997. Energy concentration of high oil corn varieties for pigs. J. Anim. Sci. 75:430–436.[Abstract/Free Full Text]

AOAC. 1990. Official Methods of Analysis. 15th ed. Assoc. Off. Anal. Chem., Washington, DC.

Averette Gatlin, L., M. T. See, J. A. Hansen, D. Sutton, and J. Odle. 2002. The effects of dietary fat sources, levels, and feeding intervals on pork fatty acid composition. J. Anim. Sci. 80:1606–1615.[Abstract/Free Full Text]

Carr, S. N., P. J. Rincker, J. Killefer, D. H. Baker, M. Ellis, and F. K. McKeith. 2005. Effects of different cereal grains and ractopamine hydrochloride on performance, carcass characteristics, and fat quality in late-finishing pigs. J. Anim. Sci. 83:223–230.[Abstract/Free Full Text]

CCAC. 1993. Guide to care and use of experimental animals. Vol. 1, 2nd ed. Canadian Council on Animal Care, Ottawa, ON. Canada.

CIE. 1976. Supplement 2 to Commission Internationale d’Eclairage Publication No. 15 (E-1.3.1) 1978, 1971/(TC-1-3). Recommendations on uniform color spaces-color difference equations, psycho-metric color terms. Commission Internationale de l’Eclairage, Paris, France.

Dwyer, L. M., R. I. Hamilton, H. N. Hayhoe, and W. Royds. 1991. Analysis of biological traits contributing to grain yield of short-to mid-season corn (Zea mays L.) hybrids. Can. J. Plant Sci. 71:535–541.

ECE. 1997. UN/ECE standard for porcine carcasses and cuts. Available: http://www.unece.org/trade/agr/standard/meat/porcine/porcine.e/porky2.pdf Accessed Sep. 15, 2004.

Folch, J., M. Lees, and G. H. Stanley. 1957. A simple method for the isolation and purification of total lipids from animal tissues. J. Biol. Chem. 226:497–509.[Free Full Text]

Houben, J. H., and B. Krol. 1980. Acceptability and storage stability of pork products with increased levels of polyunsaturated fatty acids. Meat Sci. 5:57–70.

Hyun, Y., G. E. Bressner, M. Ellis, A. J. Lewis, R. Fischer, E. P. Stanisiewski, and G. F. Hartnell. 2004. Performance of growing-finishing pigs fed diets containing Roundup Ready corn (event nk603), a nontransgenic genetically similar corn, or conventional corn line. J. Anim. Sci. 82:571–580.[Abstract/Free Full Text]

Hyun, Y., G. E. Bressner, R. L. Fischer, P. S. Miller, M. Ellis, B. A. Peterson, E. P. Stanisiewski, and G. F. Hartnell. 2005. Performance of growing-finishing pigs fed diets containing YieldGard Rootworm corn (MON 863), a nontransgenic genetically similar corn, or conventional corn hybrids. J. Anim. Sci. 83:1581–1590.[Abstract/Free Full Text]

MAFRI. 2004. Corn Production in Manitoba. Available: http://www.gov.mb.ca/agriculture/crops/specialcrops/bii01s00.html Accessed Jan. 2, 2004.

Moeser, A. J., I. B. Kim, E. Van Heugten, and T. A. T. G. Kempen. 2002. The nutritional value of degermed, dehulled corn for pigs and its impact on the gastrointestinal tract and nutrient excretion. J. Anim. Sci. 80:2629–2638.[Abstract/Free Full Text]

NPPC. 2000. Pork composition and quality assessment procedures. Natl. Pork Producers Counc., Des Moines, IA.

NRC. 1998. Nutrient Requirements of Swine. 10th rev. ed. Natl. Acad. Press, Washington, DC.

Opapeju, F. O. 2005. Nutritive value of Manitoba-grown corn (Zea mays L.) cultivars for swine. M.Sc. Thesis, Univ. Manitoba, Winnipeg, MB, Canada.

Piedrafita, J., L. L. Christian, and S. M. Lonergan. 2001. Fatty acid profiles in three stress genotypes and relationships with swine, carcass and meat quality traits. Meat Sci. 57:71–77.[CrossRef]

Prache, S., A. Priolo, and P. Grolier. 2003. Persistence of carotenoid pigments in the blood of concentrate-finished grazing sheep: Its significance for the traceability of grass-feeding. J. Anim. Sci. 81:360–367.[Abstract/Free Full Text]

Rentfrow, G., T. E. Sauber, G. L. Allee, and E. P. Berg. 2003. The influence of diets containing either conventional corn, conventional corn with choice white grease, high oil corn, or high oil high oleic corn on belly/bacon quality. Meat Sci. 64:459–466.[CrossRef]

Robertson, W. M., S. Jaikaran, L. E. Jeremiah, D. F. Salmon, F. X. Aherne, and S. J. Landry. 1999. Meat quality and palatability attributes of pork from pigs fed corn, hulless barley or triticale based diets. Proc. Advances in Pork Production. Available: http://www.banffpork.ca/proc/1999pdf/Meats.pdf Accessed Aug. 18, 2004.

Sproule, A. M., S. O. Saldivar, A. J. Bockholt, and E. J. Gregg. 1988. Nutritional evaluation of tortillas and tortilla chips from quality protein maize. Cereal Foods World 33:233–236.

Warnants, N. M., M. J. Van Oeckel, and C. V. Boucque. 1998. Effect of incorporation of dietary polyunsaturated fatty acids in pork backfat on the quality of salami. Meat Sci. 49:435–445.

Warnants, N. M., M. J. Van Oeckel, and C. V. Boucque. 1999. Incorporation of dietary polyunsaturated fatty acids into pork fatty tissues. J. Anim. Sci. 77:2478–2490.[Abstract/Free Full Text]



This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Opapeju, F. O.
Right arrow Articles by Sapirstein, H. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Opapeju, F. O.
Right arrow Articles by Sapirstein, H. D.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS