The impact of overnight lairage on meat quality and storage stability of pork loin.

Lairage, a part of the animal welfare practices, has been known to mitigate pre-slaughter stress in animals. However, research investigating the relationship between lairage and pork meat quality remains scarce. In this study, we conducted a comparative analysis of the physicochemical quality and storage stability of pork from pigs subjected to immediate slaughter (CON) and those provided with a 24 h lairage before slaughter (LRG) over a 7-day storage period. The loins from 20 castrated pigs in each group, respectively, were collected at 1, 3, 5, and 7 days and used for analysis of meat quality and storage stability, including pH, meat color, moisture, water holding capacity, drip loss, cooking loss, shear force, fatty acid composition, lipid oxidation, antioxidant activity, and electrical resistance. Overall, there were no significant differences in physicochemical meat quality parameters between CON and LRG groups. Similarly, no differences were observed in the storage stability of pork including 2-thiobarbituric acid reactive substances, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and electrical resistance. However, the proportion of unsaturated fatty acids was significantly higher in LRG compared to CON. In conclusion, 24 h lairage for castrated pigs had limited impact on meat quality and storage stability but led to an increase in the unsaturated fatty acid proportion.

Comparative review of muscle fiber characteristics between porcine skeletal muscles.

Meat derived from skeletal muscles of animals is a highly nutritious type of food, and different meat types differ in nutritional, sensory, and quality properties. This study was conducted to compare the results of previous studies on the muscle fiber characteristics of major porcine skeletal muscles to the end of providing basic data for understanding differences in physicochemical and nutritional properties between different porcine muscle types (or meat cuts). Specifically, the muscle fiber characteristics between 19 major porcine skeletal muscles were compared. The muscle fibers that constitute porcine skeletal muscle can be classified into several types based on their contractile and metabolic characteristics. In addition, the muscle fiber characteristics, including size, composition, and density, of each muscle type were investigated and a technology based on these muscle fiber characteristics for improving meat quality or preventing quality deterioration was briefly discussed. This comparative review revealed that differences in muscle fiber characteristics are primarily responsible for the differences in quality between pork cuts (muscle types) and also suggested that data on muscle fiber characteristics can be used to develop optimal meat storage and packaging technologies for each meat cut (or muscle type).

Methods for improving meat protein digestibility in older adults.

This review explores the factors that improve meat protein digestibility and applies the findings to the development of home meal replacements with improved protein digestion rates in older adults. Various methods improve the digestion rate of proteins, such as heat, ultrasound, high pressure, or pulse electric field. In addition, probiotics aid in protein digestion by improving the function of digestive organs and secreting enzymes. Plant-derived proteases, such as papain, bromelain, ficin, actinidin, or zingibain, can also improve the protein digestion rate; however, the digestion rate is dependent on the plant enzyme used and protein characteristics. Sous vide processing improves the rate and extent of protein digestibility, but the protein digestion rate decreases with increasing temperature and heating time. Ultrasound, high pressure, or pulsed electric field treatments degrade the protein structure and increase the proteolytic enzyme contact area to improve the protein digestion rate.

Carcass trait, meat yield and quality characteristics of recently-synthesized Woori Heukdon and commercial LYD pigs under identical rearing condition.

OBJECTIVE: For decades, LYD ([Landrace×Yorkshire] ♀×Duroc ♂) pigs are the most commonly-used commercial breed for meat production in Korea. Recently, due to the increasing demand for premium pork, the National Institute of Animal Science (Korea) has synthesized a novel pig breed named Woori Heukdon (WHD). This study aimed at comparing the carcass traits, meat yield and quality characteristics between the LYD and WHD pigs under identical rearing condition. METHODS: The WHD and LYD pigs (n = 15 each) were reared under identical conditions and fed the same commercial diet until reaching recommended market weight (100 to 120 kg). After slaughter, the carcasses were evaluated for traits and meat yield, and the meat quality was assessed on shoulder butt and belly cuts. RESULTS: Although no significant differences (p>0.05) occurred in slaughter weight between two pig types, WHD had a lower meat yield (by about 6 kg corresponding to approximately 7%) compared to the LYD pigs (p<0.05). The WHD had a higher fat content (by 4.26% and 13.52% in the shoulder butt and belly, respectively) compared to those of LYD pigs (p<0.05). The WHD meat showed a lower cooking loss and higher a* (redness) value (p<0.05). The WHD belly had a significantly (p<0.05) higher oleic acid content and concentrations of nonanal, octanal and decanal associated with fatty odor while, the LYD meat had a higher number of pyrazines associated with roasty odor. Regarding sensory quality, higher flavor, juiciness, and acceptability higher scores were given for the WHD meat than for the LYD meat (p<0.05). CONCLUSION: Under identical rearing conditions the WHD exhibited a better meat quality and sensory properties. However, the use of this diet resulted in a high fat level that may be associated with high trimming loss for the WHD.

Correlation Between Third Dose of COVID-19 Vaccines and Regional Case Fatality Rates During the Omicron Wave in Korea.

This study seeks to find the correlation between case fatality rates (CFRs) and third-dose vaccination coverage in 244 counties (si/gun/gu) of South Korea during the omicron variant wave. Multivariate regression analyses report that the higher third-dose vaccination rates were correlated with lower regional CFRs, when controlling for age structure. If the third-dose vaccination rate of a county is higher by 10%, it would have a CFR lower by 0.05% (95% confidence interval, 0.03-0.08%). As the number of cumulative confirmed cases in South Korea was 16,353,495 as of April 20, 2022, a lower CFR by 0.03-0.08% is equivalent to 4,394-12,448 lives (8.6-24.4 per 100,000) spared. County-specific characteristics, such as age structure, intensive care unit availability, and the level of non-pharmaceutical interventions may also affect the extent of this correlation. The conclusion implicates the potential role of coronavirus disease 2019 vaccines in reducing the pressure on the regional healthcare capacity.

Comparison of Meat Quality and Muscle Fiber Characteristics between Porcine Skeletal Muscles with Different Architectures.

This study aimed to compare the similarities, physicochemical properties, and muscle fiber characteristics of porcine skeletal muscles. Fourteen types of muscles were collected from nine pig carcasses at 24 h post-mortem and classified by muscle architecture into two main groups, namely parallel and pennate. The muscles were further differentiated into three subtypes per group. These included fan-shaped, fusiform, and strap for the parallel group, and unipennate, bipennate, and multipennate for the pennate group. Parallel-fibered muscles, which were composed of larger I, IIA, IIX, and IIXB fibers and a lower density of IIA fibers, showed higher redness and yellowness values than pennate-fibered muscles (p<0.05). However, the relative fiber area was not significantly different between the parallel and pennate groups (p>0.05). In the subtypes of parallel architecture, the strap group showed lower moisture content and higher redness values than the other subtypes and had considerably higher amounts of oxidative fibers (I and IIA; 72.3%) than the fan-shaped and fusiform groups (p<0.05). In the pennate group, unipennate showed comparatively lower moisture content and higher lightness than other pennate subtypes and was composed of smaller I, IIA, and IIX fibers than the bipennate and multipennate groups (p<0.05). Finally, a different trend of muscle clustering by hierarchical cluster analysis was found between physicochemical properties and muscle fiber characteristics. These results suggest that the physicochemical properties and muscle fiber characteristics of porcine skeletal muscles are not significantly dependent on morphological properties but are rather related to the intrinsic properties of the individual muscles.

Application of a Newly Developed Chitosan/Oleic Acid Edible Coating for Extending Shelf-Life of Fresh Pork.

This study aimed at evaluating the applicability of a newly-developed chitosan/oleic acid edible coating for extending the shelf-life of fresh pork under aerobic-packaging conditions. Various coating formulations were used: 2% chitosan alone (CHI), 0.5% (v/v) oleic acid in 2% chitosan (CHI/0.5%OA) and 1% (v/v) oleic acid in 2% chitosan (CHI/1%OA) were prepared. For coating, fresh pork slices were fully immersed in the coating solutions for 30 s and dried naturally at 4 °C for 30 min. The coated samples were placed on trays, over-wrapped with plastic film, stored at 4 °C for 21 days, and were analyzed for shelf-life stability. Samples without coating were used as control. It was found that the aerobic bacteria and Pseudomonas spp. counts, and total volatile basic nitrogen (TVBN) content were almost two to three times lower in the CHI/OA-coated samples compared to the control after 21 days of storage (p < 0.05). The CHI/OA coating combination completely inhibited growth of E. coli, and protected the meat from discoloration after 21 days of storage. In particular, the addition of OA increased the concentration of volatiles associated with pleasant aromas. This study provides an application potential of chitosan/oleic acid edible coating in preservation of fresh pork to prolong the shelf-life and improve safety.

Microneedle patch as a new platform to effectively deliver inactivated polio vaccine and inactivated rotavirus vaccine.

We recently reported a lack of interference between inactivated rotavirus vaccine (IRV) and inactivated poliovirus vaccine (IPV) and their potential dose sparing when the two vaccines were administered intramuscularly either in combination or standalone in rats and guinea pigs. In the present study, we optimized the formulations of both vaccines and investigated the feasibility of manufacturing a combined IRV-IPV dissolving microneedle patch (dMNP), assessing its compatibility and immunogenicity in rats. Our results showed that IRV delivered by dMNP alone or in combination with IPV induced similar levels of RV-specific IgG and neutralizing antibody. Likewise, IPV delivered by dMNP alone or in combination with IRV induced comparable levels of neutralizing antibody of poliovirus types 1, 2, and 3. We further demonstrated high stability of IRV-dMNP at 5, 25, and 40 °C and IPV-dMNP at 5 and 25 °C, and found that three doses of IRV or IPV when co-administered at a quarter dose was as potent as a full target dose in inducing neutralizing antibodies against corresponding rotavirus or poliovirus. We conclude that IRV-IPV dMNP did not interfere with each other in triggering an immunologic response and were highly immunogenic in rats. Our findings support the further development of this innovative approach to deliver a novel combination vaccine against rotavirus and poliovirus in children throughout the world.

The significant influences of pH, temperature and fatty acids on meat myoglobin oxidation: a model study.

Colour is one of the important quality traits affecting the meat purchasing decision by consumers, and myoglobin is the principal heme protein responsible for the meat colour. This study aimed to investigate the effects of pH (5.3, 5.8, 6.4 and 7.4) and temperature (4 and 25 °C) on oxymyoglobin (OxyMb) oxidation in model reaction mixtures containing OxyMb, fatty acids (C18:2n-6 and C18:3n-3) and vitamin E. A decrease of the OxyMb concentration with increased acidity was observed for all the reaction mixtures with/without fatty acids and vitamin E. After 48 h of storage at 4 °C, the OxyMb concentration decreased by approximately 60-70%, 61-69%, 53.7-53.9% and 40.93-41.84% in the reaction mixtures containing [OxyMb + C18:2n-6 or C18:3n-3] at pH 5.3, 5.8, 6.4 and 7.4, respectively. While, after 48 h at 25 °C, the OxyMb concentration decreased by 95-98% in all the reaction mixtures containing [OxyMb + C18:2n-6 or C18:3n-3] under all the pH conditions. The presence of vitamin E significantly inhibited the OxyMb oxidation in the reaction mixtures containing fatty acids under acidic conditions, but a higher level of vitamin E may be required for meat(s) containing high n-3 fatty acids content that are stored at high temperature.

Back-fat thickness as a primary index reflecting the yield and overall acceptance of pork meat.

Predicting aspects of lean meat yield and eating quality of pork based on some particular carcass traits become increasingly important from an economic profitability point of view. The present study aimed to determine the relationship between the back-fat (BF) thickness with lean meat yield and meat quality traits of crossbred pigs. A total of 220 crossbred pigs [(Landrace × Yorkshire) ♀ × Duroc ♂] reared under identical conditions and harvested at 180 days old were slaughtered and screened for BF thickness. Four BF thickness groups: 12-15, 16-20, 21-25, and 26-30 mm were classified, and longissimus dorsi (LD) muscles from these groups were used to analyze meat quality characteristics. Results showed that increasing BF thickness decreased the lean meat yield and loin lean area. Increasing BF thickness up to 26-30 mm increased intramuscular fat content and pH of LD muscles. The LD muscles of the thicker BF (21-30 mm) groups received significantly higher flavor, juiciness, and overall acceptability scores than those of the thinner back-fat (12-20 mm) groups. Overall, when all the pre-harvest factors are kept the same, BF thickness could be considered as a primary index for predicting lean meat yield, and the minimal back-fat thickness of 21-30 mm is required to improve the overall acceptability of pork meat.

Meat quality characteristics of pork bellies in relation to fat level.

OBJECTIVE: Pork belly is considered as the most commercially important and preferable primal cut by consumers worldwide. Thus, this study was conducted to determine the effects of fat levels on the meat quality characteristics of pork bellies. METHODS: Seventy-eight growing-finishing pigs collected from different commercial pig farms were slaughtered and used in the present study. After slaughter 24 h, bellies were fabricated according to the Korean Pork Cutting Specification, and immediately sampled for analysis of their fat content. Based on the fat levels, the bellies were segregated into three different groups: low fat (LF, fat ≤20%, n = 15), medium fat (MF, fat 21% to 30%, n = 30), and high fat (HF, fat ≥31%, n = 33). The bellies were then analyzed for meat quality traits, fatty acids, flavor compounds and eating quality properties. RESULTS: The HF group had lower moisture and cooking loss levels compared to the other groups (p<0.05). The LF group presented higher proportions of polyunsaturated fatty acids compared to the other groups (p<0.05). The LF group showed higher amounts of the Maillard reaction-derived flavor compounds (e.g., 2,5-dimethyl pyrazine, 2-ethyl-3,5-dimethyl, and 4-methylthiazole) associated with meaty and roasty flavors whereas, the HF group showed higher amounts of oleic acid- derived compounds (e.g., nonanal and octanal) associated with the fatty and oily flavors. Interestingly, significantly higher scores for all the eating quality attributes (flavor, juiciness, tenderness, and overall acceptance) were found in the HF group compared to those in the LF or MF group (p<0.05). CONCLUSION: The high-fat bellies (fat ≥31%) had a better technological quality and eating quality compared to the low-fat bellies (fat ≤20%). Thus, increasing the fat content may improve the technological quality and eating quality traits of pork bellies, however, this increase may also result in more trimmed loss due to excessively deposited body fat.

Relationship between body size traits and carcass traits with primal cuts yields in Hanwoo steers.

OBJECTIVE: This study was conducted to evaluate the correlation between body size traits, carcass traits, and primal cuts in Hanwoo steers. METHODS: Sixty-one beef carcasses were classified for conformation and primal cut weight. Additionally, carcass weight, fat thickness, carcass dimensions, and longissimus muscle area were determined to complement the grading. RESULTS: The average live weight and cold carcass weight were 759 and 469 kg, respectively. The mean carcass meat, fat, and bone proportions were 551, 298, and 151 g/kg, respectively. Primal cuts weights showed significant positive correlations (p<0.001) of 0.42 to 0.82 with live weight, carcass weight, and longissimus muscle area and a significant negative correlation with carcass fat (without shank, -0.38 to -0.10). Primal cut weights were positively correlated (p<0.01) with carcass length (0.41 to 0.77), forequarter length (0.33 to 0.57), 6th lumbar vertebrae-heel length (0.33 to 0.59), 7th cervical vertebrae carcass breadth (0.35 to 0.58), 5th to 6th thoracic vertebrae breadth (0.36 to 0.65), 7th to 8th thoracic vertebrae girth (0.38 to 0.63), and coxae girth (0.34 to 0.56) and non-significantly related to cervical vertebrae length and coxae thickness. CONCLUSION: There was a high correlation among live weight, carcass weight, longissimus muscle area, carcass length, 7th cervical vertebrae carcass breadth, 5th to 6th thoracic vertebrae breadth, and 7th to 8th thoracic vertebrae girth of the primal cuts yield. The correlation between fat and primal cut yields was highly significant and negative. Carcass length and 7th to 8th thoracic vertebrae girth, appear to be the most important traits affecting primal cut yields.

Metagenomic sequencing generates the whole genomes of porcine rotavirus A, C, and H from the United States.

The genus Rotavirus comprises eight species, designated A to H, and two recently identified tentative species I in dogs and J in bats. Species Rotavirus A, B, C and H (RVA, RVB, RVC and RVH) have been detected in humans and animals. While human and animal RVA are well characterized and defined, complete porcine genome sequences in the GenBank are limited compared to human strains. Here, we used a metagenomic approach to sequence the 11 segments of RVA, RVC and RVH strains from piglets in the United States (US) and explore the evolutionary relations of these RV species. Metagenomics identified Astroviridae, Picornaviridae, Caliciviridae, Coronoviridae in samples MN9.65 and OK5.68 while Picobirnaviridae and Arteriviridae were only identified in sample OK5.68. Whole genome sequencing and phylogenetic analyses identified multiple genotypes with the RVA of strain MN9.65 and OK5.68, with the genome constellation of G5/G9-P[7]/P[13]-I5/I5- R1/R1-C1-M1-A8-N1-T7-E1/E1-H1 and G5/G9-P[6]/P[7]-I5-R1/R1-C1-M1-A8-N1-T1/T7-E1/E1-H1, respectively. The RVA strains had a complex evolutionary relationship with other mammalian strains. The RVC strain OK5.68 had a genome constellation of G9-P[6]-I1-R1-C5-M6-A5-N1-T1-E1-H1, and shared an evolutionary relationship with porcine strains from the US. The RVH strains MN9.65 and OK5.68 had the genome constellation of G5-P1-I1-R1-C1-M1-A5-N1-T1-E4-H1 and G5-P1-I1-R1-C1-M1-A5-N1-T1-E1-H1, indicating multiple RVH genome constellations are circulating in the US. These findings allow us to understand the complexity of the enteric virome, develop improved screening methods for RVC and RVH strains, facilitate expanded rotavirus surveillance in pigs, and increase our understanding of the origin and evolution of rotavirus species.

Quality characteristics, fatty acid profiles, flavor compounds and eating quality of cull sow meat in comparison with commercial pork.

OBJECTIVE: Although the slaughter of cull sows (CS) for human consumption and meat products processing appears quite common throughout the world, relatively limited scientific information regarding the meat quality parameters of this pork type is available. The present study aimed at providing the technological quality characteristics and eating quality of CS meat, and comparing with those of commercial pork. METHODS: Longissimus thoracis et lumborum muscle samples of CS and finisher pigs (FP) at 24 h postmortem were collected and used for investigation of the meat quality traits (pH, color, shear force, cooking loss, water holding capacity), fatty acids, flavor compounds and sensory characteristics. RESULTS: The CS meat had significantly higher moisture content (p = 0.0312) and water holding capacity (p = 0.0213) together with lower cooking loss (p = 0.0366) compared to the FP meat. The CS meat also exhibited higher (p = 0.0409) contents of unsaturated fatty acids, especially polyunsaturated fatty acids (PUFA, p = 0.0213) and more desirable PUFA/total saturated fatty acids ratio (p = 0.0438) compared to the FP meat. A total of 56 flavor compounds were identified, amongst the amount of 16 compounds differed significantly between the two pork groups. Most of the PUFA-derived flavor compounds (e.g., hexanal, benzaldehyde, and hydrocarbons) showed higher amounts in the CS meat. While, 3-(methylthio)-propanal and 4-methylthiazole associated with pleasant aromas (meaty and roast odor notes) were only found in the FP meat. Furthermore, no differences were reported by panelists for flavor, juiciness, tenderness, and acceptability scores between the two pork groups studied. CONCLUSION: The sow meat exhibited better technological quality and its eating quality could be comparable to the commercial pork. This study provides meat processors and traders with valuably scientific information which may help to improve the utilization and consumption level of sow meat.

Quality characteristics and flavor compounds of pork meat as a function of carcass quality grade

Objective: The present work aimed at evaluating the effects of carcass quality grade on the quality characteristics of pork meat according to Korean carcass quality grade system. Method: Pork carcasses with varying in quality grades (QG): 1+ (QG1+, n=10), 1 (QG1, n=10) and 2 (QG2, n=10), were used to evaluate the relationship between carcass quality grade and meat quality. The meat quality traits, fatty acid profiles, flavor compounds and sensory qualities were measured on the longissimus dorsi muscle samples of these carcasses. Results: Pork meat of higher quality grade (GQ1+) presented significantly higher fat content (5.43%), C18:2n-6 level (19.03%) and total unsaturated fatty acids (UFA) content (62.72%). Also, the QG1+ meat was significantly higher in levels of classes of flavor compounds such as aldehydes, alcohols and hydrocarbons in comparison to those of the meat samples from the lower GQ groups. The sensory evaluation results (flavor, juiciness, tenderness and acceptability scores) of QG1+ meat was significantly higher than the QG1 and QG2 meats. The pork with lower QG (i.e., QG2) was found positively correlated to redness (r=0.987), C18:1n-9 level (r=1.000) but negatively correlated to the fat content (r=-0.949), and flavor (r=-0.870), juiciness (r=-0.861), tenderness (r=-0.862) and acceptability (r=-0.815) scores. Conclusion: The pork with higher quality grade had higher fat content, total unsaturated fatty acids and better eating quality, thus producing pork with higher quality grades should be considered in order to satisfy the consumer's expectation.

Live weights at slaughter significantly affect the meat quality and flavor components of pork meat.

One-hundred-twenty crossbred pigs finished at 175-185 days of age were used to investigate the effects of live weights at slaughter on the meat quality, volatile flavor compounds, and sensory attributes of pork meat. Based on the live weights at slaughter, three weight groups (n = 36 per group) were classified as follows: light weight (LW: 100 kg), medium weight (MW: 110 kg), and heavy weight (HW: 120 kg). After slaughter, longissimus dorsi muscle samples were taken and used for the analyses of aforementioned parameters. The HW group had higher fat content and water holding capacity compared to the LW or MW group (p < 0.05). The HW group also showed higher levels for majority of unsaturated fatty acids and total polyunsaturated fatty acids than the LW group (p < 0.05). The slaughter weight significantly affected the amounts of 11 among the 47 flavor compounds identified. Significantly higher amounts of fatty acids oxidation-derived flavor compounds (aldehydes) were found in the HW group than in the other groups. Noticeably, increasing slaughter weight was associated with higher sensorial scores for flavor, juiciness, and acceptance scores (p < 0.05). Based on the obtained results, 120 kg body weight is recommended as the market weight for this commercial breed without compromising the meat quality.

The fates of microbial populations on pig carcasses during slaughtering process, on retail cuts after slaughter, and intervention efficiency of lactic acid spraying.

This study was conducted to detect and identify microbial populations on pig carcasses at different slaughtering stages and on retail pork cuts at 24 h after slaughter as well as to evaluate the intervention efficiency of sprays containing different concentrations (2% and 4%) of lactic acid. The sprays were applied to the carcass surfaces at the end of the slaughter line. Microbial samples were collected from carcass surfaces after bleeding and after eviscerating, and from retail cuts at 24 h after chilling/spraying. The detected microorganisms were identified through using a Microflex identification instrument and 16S rRNA gene sequencing. The diversity of the bacterial genera; Staphylococcus, Salmonella, Shigella, Enterococci, Escherichia, Acinetobacter and Corynebacterium spp. showed counts ranging from 2.70 to 4.91 log10 cfu/100 cm2 on the carcasses during slaughter. Most of these genera were also detected on the carcasses after 24 h of chilling. Three species (Staphylococcus hyicus, Acinetobacter albensis, and Corynebacterium xerosis) were also found on the retail cuts of non-sprayed carcasses but not on those of the sprayed groups. Significantly greater reductions in all bacterial species were observed on the carcasses and retail cuts that were sprayed with lactic acid, particularly at the 4% level. Thus, spraying with 4% lactic acid may be an effective intervention for controlling bacterial contamination on pig carcasses to improve the microbiological safety of pork meat.

Lack of immune interference between inactivated polio vaccine and inactivated rotavirus vaccine co-administered by intramuscular injection in two animal species.

A parenteral inactivated rotavirus vaccine (IRV) in development could address three problems with current live oral rotavirus vaccines (ORV): their lower efficacy in low and middle-income countries (LMICs), lingering concerns about their association with intussusception, and their requirement for a separate supply chain with large volume cold storage. Adding a new parenteral IRV to the current schedule of childhood immunizations would be more acceptable if it could be combined with another injectable vaccine such as inactivated polio vaccine (IPV). Current plans for polio eradication call for phasing out oral polio vaccine (OPV) and transitioning to IPV, initially in LMICs as a single dose booster after two doses of OPV and ultimately as a two dose schedule. Today in many LMICs, IPV is administered as a standalone vaccine, which involves a separate cold chain and is relatively costly. We therefore tested in two animal models formulations of IPV with IRV to determine whether co-administration might interfere with the immune response to each product and spare antigen dose for both vaccines. Our results demonstrate that IRV when adjuvanted with alum and administered alone or in combination with IPV did not impair the immune responses to either rotavirus or poliovirus serotypes 1, 2 and 3. Similarly, IPV when formulated and administered alone or together with IRV induced comparable levels of neutralizing antibody to poliovirus type 1, 2 and 3. Furthermore, comparable antibody titers were observed in animals vaccinated with low, middle or high dose of IPV or IRV in combination. This dose sparing and the lack of interference between IPV and IRV administered together represent another step to support the further development of this novel combination vaccine for children.

A DS-1 like G9P[6] human strain CDC-6 as a new rotavirus vaccine candidate.

Human rotavirus vaccine Rotarix® (G1P[8]) has shown broad cross protection against homotypic and heterotypic Wa-like human rotavirus strains among children worldwide. This vaccine, however, appears to induce slightly less or non-consistent protection against DS-1 like rotavirus P[4] strains in some settings. In addition, children who are secretor or Lewis-negative and are vaccinated with Rotarix® often experience breakthrough infection with P[6] strains. By contrast, P[6] strains infect all children, irrespective of their secretor or Lewis status. In the present study, we report successful adaptation of a DS-1 like human rotavirus G9P[6] strain (CDC-6) to high growth in Vero cells and identify sequence changes that may be critical for enhanced growth in vitro and attenuation in vivo. This human G9P[6] strain could serve as a promising new and potential low-cost vaccine candidate for global use, particularly in targeted population with secretor or Lewis-negative status and high prevalent DS-1 like P[6] strains.

Effect of Proteolytic Enzymes and Ginger Extract on Tenderization of M. pectoralis profundus from Holstein Steer.

The effects of proteolytic enzymes (bromelain and bromelain+papain) and a ginger extract were assessed on collagen content and solubility, thermal shrinkage temperature of connective tissue, pH, cooking loss, drip loss, and Warner-Bratzler shear force (WBSF) of M. pectoralis profundus isolated from the beef brisket cut. Both proteolytic enzymes and ginger extract led to a significant increase in cooking loss and collagen solubility compared with untreated controls. On the other hand, the peak (Tp) thermal shrinkage temperature markedly decreased in all treatments compared with those in controls. Samples treated with bromelain, bromelain + papain, and ginger extract showed a significant decrease in WBSF by 36%, 40%, and 37%, respectively, compared with untreated controls. Our findings suggest that ginger extract are useful for postmortem tenderization of meat containing high levels of collagen, compared to control even though, bromelain and bromelain + papain treatments have higher collagen solubility than ginger extract.