• Journal of Microbiology and Biotechnology
• /
• v.19 no.3
• /
• pp.314-322
• /
• 2009

Four different bacterial colonies were isolated from an old stock of an entomopathogenic nematode, Steinernema monticolum. They all showed entomopathogenicity to final instar larvae of beet armyworm, Spodoptera exigua, by hemocoelic injection. However, they varied in colony form, susceptibility to antibiotics, and postmortem change of the infected host insects. Biolog microbial identification and 16S rDNA sequence analyses indicate that these are four different species classified into different bacterial genera. Owing to high entomopathogenicity and a cadaver color of infected insect host, Serratia sp. was selected as a main symbiotic bacterial species and analyzed for its pathogenicity. Although no virulence of Serratia sp. was detected at oral administration, the bacteria gave significant synergistic pathogenicity to fifth instar S. exigua when it was treated along with a spore-forming entomopathogenic bacterium, Bacillus thuringiensis. The synergistic effect was explained by an immunosuppressive effect of Serratia sp. by its high cytotoxic effect on hemocytes of S. exigua, because Serratia sp. caused septicemia of S. exigua when the bacterial cells were injected into S. exigua hemocoel. The cytotoxic factor(s) was present in the culture medium because the sterilized culture broth possessed high potency in the cytotoxicity, which was specific to granular cells and plasmatocytes, two main immune-associated hemocytes in insects.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.3
• /
• pp.394-400
• /
• 2013

A total of 192 broiler chicks were used to evaluate the influence of dietary ${\alpha}$-lipoic acid (ALA) on growth performance, carcass characteristics and meat quality of broiler chickens with the purpose of developing a strategy to prevent the occurrence of pale, soft, and exudative (PSE) meat and to improve the meat quality of broilers. At 22 d of age, birds were allocated to 4 ALA treatments (0, 400, 800, and 1200 ppm). The results showed that dietary ALA significantly decreased average feed intake (AFI), average daily gain (ADG), final live body weight (BW) and carcass weight (p<0.05), while no difference in feed conversion ratio (FCR) was detected among chickens fed with and without ALA. Abdominal fat weight significantly decreased (p<0.05) for broilers fed 800 and 1200 ppm ALA. However when calculated as the percentage of carcass weight there was no significant difference between control and ALA treatments. Meat quality measurements showed that dietary ALA regulated postmortem glycolysis and improved meat quality as evidenced by increased muscle pH and decreased drip loss of meat (p<0.05). Although ALA did not change the tenderness of meat as indicated by meat shear force, dietary ALA decreased collagen content and mRNA expression of COL3A1 gene (p<0.05). In conclusion, the results indicate that dietary ALA may contribute to the improvement of meat quality in broilers.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.14 no.1
• /
• pp.15-23
• /
• 1981

Protein compositions of filefish (Navoden modestus) skeletal muscle and their changes in postmortem with reference to freshness kept at $0^{\circ}C$ were investigated. The muscle protein was approximately composed of $31\%\;sarcoplasmic,\;55\%$ myofibrillar, $10\%$residual intracellular, and $4\%$stroma protein. The sarcoplasmic and myofibrillar protein decreased while the residual intracellular protein increased with the decline of freshness during post-mortem lapse. In the analysis of electrophoretograms and its densitograms, the myofibrillar protein resembled to other fishes in protein composition: $70\%$ actin and myosin, $20\%$ regulatory proteins, and $10\%$ unknown proteins. And most of the residual intracellular protein was estimated as myofibrillar protein. Troponin T, troponin C and myosin light chain 2 of the myofibrillar protein constituents were decreased during storage. Amino acid composition of the protein from the at-death muscla was similar to those of other fishes except that tryptophan and sulfur-containing amino acids were scant. Proline and cysteine were remarkably decreased whereas leucine, isoleucine and phenylalanine were slightly increased in the protein from the muscle lapsed of 18 days. In free amino acid composition, alanine, glycine, lysine, and especially taurine were rich in the at-death muscle. The muscle lapsed of 18 days showed an increase of taurine, histidine, valine and methionine, and a decrease of lysine, arginine, aspartic acid, threonine, leucine, and isoleucine.

• Biomolecules & Therapeutics
• /
• v.12 no.1
• /
• pp.43-48
• /
• 2004

The present study was carried out to investigate the potential acute toxicity of CKD-602 by a single intravenous dose in Sprague-Dawley rats. Ten males females were used in each test groups: a vehicle control, 34.7, 4l.7, 50.0, 60.0 and 72.0 mg/kg groups, and were given different single intravenous doses of CKD-602 to the test animals. Mortalities, clinical findings, and body weight changes were monitored for the 14-day period following the administration. At the end of l4-day observation period, all animals were sacrificed and complete gross postmortem examinations were performed. One, 1, 2, 8 and 9 cases of deaths occurred in the male dose groups of 34.7, 41.7, 50.0, 60.0 and 72.0 mg/kg, respectively, and 1, 5 and 9 cases in the female dose groups 50.0, 60.0 and 72.0 mg/kg, respectively. An increase in the incidence of clinical signs such as alopecia, skin pallor skin ulcerations, emaciation and change of fecal material was found in the both sexes of all treatment groups. A decrease or Suppression in the body weight was also observed in a dose-dependent manner. In autopsy, male and/or female rats of the treatment groups showed treatment-related gross findings such as splenomegaly, atrophy of the testis, epididymis, seminal vesicles, ovary, uterus and thymus which were dose-dependent in incidence and severity. Based on these results, it was concluded that a single intravenous injection of CKD-602 to rats caused significant toxicities in gastrointestinal, hematopoietic, and reproductive systems. The $LD_{50}$ value was 53.8 (95% confidence limit: 48.5~60.6) mg/kg for males and 60.l (95% confidence limit: 55.3~65.8) mg/kg for females. The $LD_{10}$ value was 39.9 (95% confidence limit: 3l.7~44.8) mg/kg for males and 50.3 (95% confidence limit: 40.6~54.8) mg/kg for females.

• Korean Journal of Veterinary Research
• /
• v.45 no.4
• /
• pp.527-536
• /
• 2005

The effects of dietary Gleditschia on fatty acid composition, lipid oxidation, and pork quality were investigated. Pigs (n=40) were fed a diet containing 0, 0.1, 0.2, 0.4, and 1% Gleditschia for 14 weeks and slaughtered at 110 kg average. The longissimus throracis et lumborum muscle was collected at 24 hr postmortem. Pork loin chops (3 cm thick) were packaged aerobically and stored at $4^{\circ}C$ for 7 days. Samples were analyzed for fatty acid composition, ultimate pH, thiobarbituric acid-reactive substance (TBARS), color ($L^*$, $a^*$, $b^*$), drip loss and water-holding capacity. There was no significant difference of moisture and crude fat percent in between treatment and control group, and the color stability of pork loin better in all treat groups was more improved during cold storage. The change of pH was significantly increased (p<0.05) in 0.2, 0.4, 1% treatment groups compare to the control group. Water-holding capacity of pig loins was significantly higher (p<0.05) in all treat groups than in control group; 0.2% treat group was the highest in the water holding capacity followed by 0.4, 1, and 0.1% treat groups. Less drip loss of pig loin was observed with samples from Gleditschia-fed pigs except 1% treat group. Unsaturated fatty acid were tend to be decreased and saturated fatty acid were tend to be increased in Gleditschia-treated group. Thiobarbituric acid-reactive substance value of control was significantly higher than that of the Gleditschia-fed group (p<0.05).

• Animal Bioscience
• /
• v.34 no.6
• /
• pp.1070-1077
• /
• 2021

Objective: An experiment was conducted to determine the appropriate fasting time prior to slaughter for broilers in floor-feed and scatter-feed mode. Methods: On 21 d since hatching, 120 Arbor Acres broilers were divided into floor-feed and scatter-feed groups, chicks from each group were further assigned to feed withdrawal treatments for 0, 4, 6, 8, and 10 h. Some resultant indicators such as carcass contamination, body weight loss, meat quality of 54-day-old broilers were measured. Results: It appears that longer feed withdrawal increased weight loss, lightness, drop loss of meat but reduced pH. A significant higher weight loss and lightness for both floor-feed and scatter-feed chicks coincided after 6 to 10 h feed withdrawal (p<0.05). pH for breast muscle at 45 min postmortem reduced when chicks of scatter-feed were fasted 6 and 10 h, while the reduction of floor-feed group occurred only in 10 h (p<0.05). A noticeable effect of feed withdrawal on drop loss occurred after 10 h fasting in scatter-feed of which drop loss were significantly higher than that for other groups including control (p<0.05). The change of contamination propensity revealed that 6 to 10 h fasting significantly reduced the likelihood of carcass contamination under both floor-feed and scatter-feed (p<0.05). Net weights of intestinal contents for gizzard were significantly reduced after feed deprived for 10 h in floor-feed and 6 and 10 h in scatter-feed (p<0.05). The decrease for whole intestine occurred after floor-feed broilers have been without feed for more than 4 h, scatter-feed broilers for more than 8 h (p<0.05). Conclusion: On the premise that poultry product properties and welfare were not significantly damaged, proper fasting time could reduce carcass contamination. Current data implied that 6 h fasting was recommendable for both floor and scatter feed pre-slaughter broilers.

• Food Science of Animal Resources
• /
• v.38 no.6
• /
• pp.1131-1143
• /
• 2018

This study aimed to investigate the drying yield, meat quality, oxidation stability and sensory properties of Hanwoo beef loin subjected to different dry-aging conditions. A total of 54 Hanwoo beef loins (bone-in, $6^{th}-13^{th}$ ribs) with fat cover at 2 d postmortem were assigned to four groups and hung in a dry-aging room at a controlled temperature ($2^{\circ}C-4^{\circ}C$), humidity (65%-85%) and air velocity (3 m/s). Four treatment conditions were tested; the respective temperature, humidity and treatment duration are as follows: T1, $2^{\circ}C$, 85%, 60 d; T2, $2^{\circ}C$, 65%, $20d+2^{\circ}C$, 75%, $20d+4^{\circ}C$, 85%, 20 d; T3, $2^{\circ}C$, 75%, $20d+4^{\circ}C$, 85%, 40 d; T4, $4^{\circ}C$, 85%, 60 d. The drying yield, total aerobic counts and fat contents increased, whereas the moisture content, meat color (CIE $L^*$, $a^*$, and $b^*$), and Warner-Bratzler shear force values decreased significantly during the aging period for all treatments (p<0.05). The cooking loss (%) did not change significantly until 40 d, and it was significantly higher in T1 and T4 than in T2 and T3 at 60 d (p<0.05). The water-holding capacity, pH and lipid oxidation [thiobarbituric acid reactive substance (TBARS) values] increased during aging (p<0.05). The sensory scores for tenderness, juiciness, flavor, and overall acceptability of dry-aged loin muscles increased as the aging period increased. T2 and T3 had significantly higher sensory scores and T1 had significantly lower scores for tenderness, juiciness, flavor, and overall acceptability at 20, 40, and 60 d for loin muscles (p<0.05).