• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.4
• /
• pp.576-584
• /
• 2018

Objective: This study aimed to develop a value-added product concerning technological and sensory characteristics changes of the use of mechanically deboned poultry meat (MDPM) as meat replacer in lamb and mutton emulsion-type sausages (mortadella). Methods: Sausages were produced with lamb and mutton and with different contents of MDPM. Six treatments, using lamb or mutton and 0%, 30%, and 60% of MDPM in relation to the meat batter, were produced and analyzed for pH, proximal composition, calcium and residual nitrite content, water activity, 2-thiobarbituric acid reactive substances (TBARS), instrumental color and texture profile. The sensory profile of the mortadella's was also evaluated by acceptance test and check-all-that-applies (CATA) analysis. Results: The MDPM addition increased (p<0.05) fat, residual nitrite and calcium content in the all sausage formulations, but mutton sausage had (p<0.05) higher fat and lower moisture content than lamb sausage. The pH, water activity, TBARS index and color was not affected by MDPM additions, while the mutton sausages were significantly redder (higher $a^*$, $C^*$, and lower $h^{\circ}$) and darker (lower $L^*$) than lamb sausages. Adding up to 60% of MDPM reduced (p<0.05) sausages hardness and chewiness. Overall, the meat replacement by MDPM increased the sausages acceptance, but the mutton sausage with 30% of MDPM replacer were the most preferred. Consumers related that pink color, glossy appearance, poultry meat-like taste, soft texture, juicy and greasy mouth feel to all sausages contain MDPM according to CATA analysis. Conclusion: Mutton from culled ewes can be utilized for mortadella production with 30% replacement of lean mutton and fat by MDPM.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.11
• /
• pp.1547-1554
• /
• 2009

This study was carried out to evaluate the effects of dietary supplementation of different sources of chromium on growth performance, blood profile and carcass trait in growing-finishing pigs. A total of 200 growing pigs (Landrace${\times}$Yorkshire)${\times}$Duroc, average initial weight 8.5 kg) were allotted to 5 treatments with 4 replicates per treatment and 10 pigs per replicate. Five treatments were designated as follows according to the source of chromium. i) Control (No chromium): corn-soybean meal based basal diet, ii) $CrCl_{3}$: control diet+200 ppb Cr as $CrCl_{3}$, iii) CrPic: control diet+200 ppb Cr as Cr picolinate, iv) CrMet-1: control diet+100 ppb Cr as Cr methionine, and v) CrMet-2: control diet+200 ppb Cr as Cr methionine. After the feeding trial, three pigs per replicate (12 pigs per treatment) were slaughtered for the evaluation of carcass traits. Average daily gain (ADG), average daily feed intake (ADFI), and feed: gain ratio (F/G) were not different (p>0.05) among dietary Cr sources. However, whole-period ADG of pigs fed CrPic, CrMet-1 and CrMet-2 diets was higher (p<0.05) than for the control diet. Nutrient digestibility was not different (p>0.05) among dietary Cr sources, but the nutrient digestibility of pigs fed CrPic, CrMet-1 and CrMet-2 diets was higher (p<0.05) than for the control diet. BUN level decreased with more magnitude (p<0.05) in pigs fed Cr during the 20 to 50 kg period. Although both serum cholesterol and triglyceride were different (p<0.05) among treatments, there was no consistent response that could be related to the dietary Cr sources regardless of growth phase. However, the overall data suggested that serum cholesterol level increased as BW of pigs increased. Blood total protein (TP) increased (p<0.05) in pigs fed Cr only during the 90-110 kg phase, and blood creatinine (Creat) level was higher in $CrCl_{3}$ and CrPic treatments than in the control only during the 90-110 kg phase. Backfat thickness was thinner (p<0.05) in pigs fed CrMet-2 than in the control treatment. Therefore, lean percentage was higher (p<0.05) in CrMet-2 than in control pigs. However, dressing percentage and Longissimus muscle area (LMA) were not different (p>0.05) among treatments. In conclusion, dietary supplementation of 200 ppb Cr, via either CrPic or CrMet, improved pig growth performance and nutrient digestibility. Moreover, dietary CrMet supplementation for the growing-finishing pig is evidently remarkable for improving both lean percentage of the carcass and backfat thickness.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.8
• /
• pp.1069-1077
• /
• 2009

Castration of male pig produces significant negative effects on skeletal muscle development. The androgen receptor (AR), two splice variants of insulin-like growth factor-I (IGF-I Ea and MGF) and the myostatin gene may play important roles in this process. In the present study, the expression of AR, IGF-I Ea, MGF and myostatin genes in three skeletal muscles, the brachialis, longissimus and semitendinosus, were studied using real-time quantitative RT-PCR. Our experimental design used 14 pairs of male Landrace sire${\times}$Yorkshire dam piglets. The two piglets in each pair were full sibs, one of which was castrated at 21 d of age; the other remained intact. The study group was divided into subgroups of equal size. Animals in the first subgroup were slaughtered at 147 d and those of the second at 210 d of age. Carcass weight and lean meat yield were similar between boars and barrows at 147 d of age (p>0.05), whereas barrows had lower carcass weight and less lean meat yield at 210 d of age (p<0.05). Castration caused down-regulation of AR gene expression at both 147 and 210 d of age (p<0.05). The two splice variants of the IGF-I gene from porcine skeletal muscle were cloned using RT-PCR, and it was found that MGF differs from IGF-I Ea in having a 52-base insert in the last coding exon of the mRNA. Both splice variants were down-regulated by castration only at 210 d of age (p<0.05). No differences in expression of the myostatin gene were observed between boars and barrows at either 147 or 210 d of age (p>0.05). These results suggest that the downregulation of AR, IGF-I Ea and MGF gene expression following castration helps to explain the negative effect of castration on skeletal muscle development.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.5
• /
• pp.725-732
• /
• 2012

This study was carried out to investigate the effects of hydrated potato starch on the quality of low-fat ttoekgalbi (Korean traditional patty) packaged in modified atmosphere conditions during storage. The ttoekgalbi was prepared from 53.2% lean beef, 13.9% lean pork, 9.3% pork fat, and 23.6% other ingredients. Two low-fat ttoekgalbi treatments were prepared by substituting pork fat with hydrated potato starch; either by 50% fat replacement (50% FR) or 100% fat replacement (100% FR). Both 50% and 100% FR increased the moisture, crude protein, and decreased fat content, cooking loss, and hardness. For MAP studies, 200 g of ttoekgalbi were placed on the tray and filled with gas composed of 70% $O_2$: 30% $CO_2$ (70% $O_2$-MAP) and 30% $CO_2$: 70% $N_2$ (70% $N_2$-MAP), and were stored at $5^{\circ}C$ for 12 d. During the storage time, both 50% and 100% FR showed higher protein deterioration, while no differences were found in CIE $a^*$, CIE $L^*$, lipid oxidation, and bacterial counts in comparison to control. The ttoekgalbi with 70% $O_2$-MAP was more red, lighter in color, and showed higher TBARS values compared with 70% $N_2$-MAP. The meat with 70% $N_2$-MAP showed lower aerobic bacterial counts in control than those with 70% $O_2$-MAP. The lower anaerobic bacterial counts were observed only in 50% FR and 100% FR packed with 70% $N_2$-MAP in comparison with 70% $O_2$-MAP. In conclusion, the fat replacement with hydrated potato starch showed no negative effects on the quality of low fat ttoekgalbi during storage and 70% $N_2$-MAP was better than 70% $O_2$-MAP for low-fat ttoekgalbi packaging.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.5
• /
• pp.704-710
• /
• 2005

The objective of this experiment was to compare corn and wheat in finishing pig diets in order to determine whether performance, carcass quality, fatty acid composition or fat colour is altered by choice of cereal grain. A total of 126 crossbred pigs were used in this experiment. At the start of the experiment, a portion of the experimental animals were assigned to receive a wheat-based diet formulated using soybean meal as the sole source of supplementary protein. The remainder of the pigs were assigned to a corn-based diet formulated to supply a similar level of lysine (0.65%) and energy (3,300 kcal/kg DE). At two week intervals, a portion of the pigs on the corn-based diet were switched to the wheat-based diet so that a gradient was produced with pigs being fed the corn and wheatbased diets for different proportions of the finishing period ranging from 100% on wheat to 100% on corn. There were no significant differences in the growth rate of pigs fed the two diets (p = 0.834). Pigs fed wheat tended to consume slightly less feed (p = 0.116) and had a significantly improved feed conversion (p = 0.048) compared with pigs fed corn. Choice of cereal did not affect dressing percentage (p = 0.691), carcass value index (p = 0.146), lean yield (p = 0.134), loin fat (p = 0.127) or loin lean (p = 0.217). Fatty acid composition of backfat was unaffected by the cereal grain fed (p>0.05). Total saturated fatty acid content was 33.31% for both corn and wheat fed pigs (p = 0.997) while the polyunsaturated fatty acid content was 12.01% for corn fed pigs and 11.21% for wheat fed pigs (p = 0.257). The polyunsaturated/saturated ratio was 0.36 for pigs fed corn and 0.34 for pigs fed wheat (p = 0.751). Hunter Lab Colour Scores indicated no difference either in the whiteness or yellowness of the fat. In conclusion, wheat can substitute for corn in growingfinishing pig rations without detrimental effects on pig performance. There were no differences in either the fatty acid composition of backfat or in backfat colour indicating that the decision to use wheat vs. corn needs to be made on economic grounds rather than being based on their effects on fat quality.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.4
• /
• pp.447-454
• /
• 2001

For determining the relative genetic effects of Duroc (D) and Taoyuan (T) breeds on the economic traits of their hybrids, 72 litters of pigs, from four mating types, namely TT (T♂$\times$T♀), DD (D♂$\times$D♀) and D-T hybrids (TD, T♂$\times$D♀ and DT, D♂$\times$T♀) were used in this study. The various crossbreeding parameters were estimated by comparisons among mating types using linear contrasts of least-square analysis. The results of reproductive traits analysis showed that T breed had contributed superior genetic effects on the total number of piglets at birth (TBN) (p<0.10) and number of live piglets at 21 days (LP21) (p<0.05) to the D-T hybrids. Estimates of maternal genetic effects showed that the T females were superior in TBN (p<0.05), but inferior in average birth weight (ABW) and average litter birth weight (LBW) (p<0.01) to the D females. Direct heterosis effects were significant for LBW, LP21 and LWT21 (p<0.01). Least-squares analysis of other economic traits showed that T breed had relative negative effects on all growth traits, withers height (WH), body type index (BTI), average backfat thickness (ABF), carcass length (LENG), loin eye area (longissimus) (LEARA), and lean percentage (LEAN) of D-T hybrids (p<0.05). Estimates of direct genetic effects showed that the D breed was superior to the T breed in all growth and carcass traits except the average backfat (BF). Estimates of maternal genetic effects showed that average body weight at 180 days (WT180) of progenies from T sows were lighter than from D sows. Progenies from D females had larger and leaner carcass than those from T females. Direct heterosis effects were significant for average daily weight gains from 150 to 180 days ($ADG_{150-180}$) (p<0.05) and for average body weights at 150 (WT150), and 180 days (WT180), average daily weight gains from birth to 150 and 180 days ($ADG_{150}$ and $ADG_{180}$, respectively), WH, body length (BL), ABF, BTI, and LENG (p<0.01). The results showed that D-T hybrids tended to have superior TBN and LP21 than D breed, and to be superior in all growth and most conformation and carcass traits to the T breed.

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.10
• /
• pp.1670-1676
• /
• 2018

Objective: This study was conducted to enable on-line prediction of primal and commercial cut weights in Korean slaughter pigs by AutoFom III, which non-invasively scans pig carcasses early after slaughter using ultrasonic sensors. Methods: A total of 162 Landrace, Yorkshire, and Duroc (LYD) pigs and 154 LYD pigs representing the yearly Korean slaughter distribution were included in the calibration and validation dataset, respectively. Partial least squares (PLS) models were developed for prediction of the weight of deboned shoulder blade, shoulder picnic, belly, loin, and ham. In addition, AutoFom III's ability to predict the weight of the commercial cuts of spare rib, jowl, false lean, back rib, diaphragm, and tenderloin was investigated. Each cut was manually prepared by local butchers and then recorded. Results: The cross-validated prediction accuracy ($R^2cv$) of the calibration models for deboned shoulder blade, shoulder picnic, loin, belly, and ham ranged from 0.77 to 0.86. The $R^2cv$ for tenderloin, spare rib, diaphragm, false lean, jowl, and back rib ranged from 0.34 to 0.62. Because the $R^2cv$ of the latter commercial cuts were less than 0.65, AutoFom III was less accurate for the prediction of those cuts. The root mean squares error of cross validation calibration (RMSECV) model was comparable to the root mean squares error of prediction (RMSEP), although the RMSECV was numerically higher than RMSEP for the deboned shoulder blade and belly. Conclusion: AutoFom III predicts the weight of deboned shoulder blade, shoulder picnic, loin, belly, and ham with high accuracy, and is a suitable process analytical tool for sorting pork primals in Korea. However, AutoFom III's prediction of smaller commercial Korean cuts is less accurate, which may be attributed to the lack of anatomical reference points and the lack of a good correlation between the scanned area of the carcass and those traits.

• Animal Bioscience
• /
• v.34 no.7
• /
• pp.1193-1201
• /
• 2021

Objective: According to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement. Methods: A total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively. Results: The results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p<0.01). LPDs were significantly higher than FPDs in breast muscle thickness, breast muscle weight, breast muscle rate and breast muscle shear force (p<0.01). The muscle fiber average area and fiber diameter of LPDs were significantly higher than those of FPDs (p<0.01). The muscle fiber density of LPDs was significantly lower than that of FPDs (p<0.01). The IMF of LPDs in the breast muscle was significantly higher than that in the FPDs (p<0.01). There was no significant difference between the 2 strains in IMP content (p>0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p<0.01), and FPDs had higher saturated fatty acid and monounsaturated fatty acid levels (p<0.05). Conclusion: Long-term breeding work resulted in vast differences between the two strains Pekin ducks. This study provides a reference for differences between LPD and FPD that manifest as a result of long-term selection.

• Journal of Animal Science and Technology
• /
• v.57 no.3
• /
• pp.8.1-8.8
• /
• 2015

Background: The demand for healthy, lean and consistent meat products containing low saturated fatty acid content and high quality polyunsaturated fatty acids (PUFA), especially long-chain (${\geq}C_{20}$) omega-3 PUFA, has increased in recent times. Fat deposition is altered by both the genetic background and dietary supplements, and this study aimed to assess the effect of dietary Spirulina supplementation levels on the mRNA expression patterns of genes controlling lipid metabolism in the subcutaneous adipose tissue (SAT) and Longissimus dorsi (ld) muscle of Australian crossbred sheep. Methods: Twenty-four weaned lambs belonging to four breeds under the same management conditions were maintained on ryegrass pasture and fed three levels of Spirulina supplement (control, low and high). In terms of nutrient composition, Spirulina is a nutrient-rich supplement that contains all essential amino acids, vitamins and minerals. It also is a rich source of carotenoids and fatty acids, especially gamma-linolenic acid (GLA) that infer health benefits. After slaughter, subcutaneous adipose tissue (SAT) and ld samples were subjected to mRNA extraction and reverse transcription using quantitative polymerase chain reaction (RT-qPCR) to assess the mRNA expression levels of the Aralkylamine N-acetyltransferase (AANAT), Adrenergic beta-3 receptor (ADRB3), B-cell translocation gene 2 (BTG2) and Fatty acid synthase (FASN) genes, which are associated with lipid metabolism. Results: Both low and high Spirulina supplementation levels strongly up-regulated the transcription of all the selected genes in both SAT and ld tissues (mostly in the subcutaneous adipose), but sheep breed and sex did not influence the gene expression patterns in these tissues. Conclusions: The evidence indicates that high Spirulina supplementation level resulted in a decrease in intramuscular fat content in Australian purebred and crossbred sheep due to the enhanced production of melatonin in sheep muscle tissues and strong up-regulation of mRNA expression of BTG2 in SAT which negatively affected fat deposition. In contrast, low Spirulina supplementation level strongly up-regulated the ADRB3 and FASN genes responsible for fat production. These findings are consistent with the observed phenotypic data suggesting that low Spirulina supplementation level can increase lamb production, with higher long-chain PUFA content.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.2
• /
• pp.161-166
• /
• 2008

To determine if body weight change is directly related to altered leptin and neuropeptide Y (NPY) gene expression, we assessed adipose tissue weight, percent body fat, leptin and NPY mRNA levels and serum leptin concentration in pigs at weights of 1, 20, 40, 60, and 90 kg. The results indicated that the weight of adipose tissues and the percent body fat of pigs significantly increased and correlated with body weight (BW) from 1 to 90 kg (p<0.01). Serum leptin concentrations and leptin mRNA levels in omental adipose tissue (OAT) increased from 1 to 60 kg, and then decreased from 60 to 90 kg. At 60 kg, the serum leptin concentration and leptin mRNA level significantly increased by 33.5% (p<0.01) and 98.2% (p<0.01), respectively, as compared with the levels at 1 kg. At 60 kg, the amount of leptin mRNA in subcutaneous adipose tissue (SAT) was significantly higher than that of 1 and 40 kg animals (p<0.05). NPY gene expression in the hypothalamus also changed with BW and at 60 kg the NPY mRNA level significantly decreased by 54.0% (p< 0.05) as compared with that in 1 kg. Leptin mRNA in OAT was correlated with serum leptin concentrations (r = 0.98, p<0.01), body weight (r = 0.82, p<0.05) and percent body fat (r = 0.81, p<0.05). This is the first report of the developmental expression of leptin in porcine OAT, peritoneal adipose tissue (PAT) and SAT, and proves that the expression of leptin in OAT could reflect the levels of circulating leptin. These results provide some information for nutritional manipulation of leptin secretion which could lead to practical methods of controlling appetite and growth in farm animals, thereby regulating and improving efficiency of lean meat production and meat production quality.