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Synergistic Effect of Nisin and Cinnamon Essential oil (Cinnamomum verum) on the Growth of Lactococcus garvieae in Fish Fillets of Rainbow Trout (Oncorhynchus mykiss)
2019
Roomiani, laleh | Roomiani, laleh | ghaeni, mansoreh
BACKGROUND: Lactococcusis disease due to Lactococcus garvieae, one of the most important zoonotic bacterial diseases. Objectives: The purpose of this study was to evaluate the effect of Cinnamon essential oil and Nisin on the growth of Lactococcus garvieae. Methods: The effect of cinnamon essential oil with concentrations of 0, 0.25 and 0.75%, and Nisin 0, 0.4 and 0.8 μg/mL on growth of this bacteria at 4 and 8 °C during 0, 3, 6, 9, 12, 15 days of storage was investigated. Results: The results of this study showed that on samples kept at 4 °C, bacterial growth was delayed until the fifteenth day using cinnamon essential oil or Nisin, and in the case of cinnamon, the growth rate of bacteria in the ninth and fifteenth days was below 2 log cfu/g. While the combination of 0.8 μg/ml Nicin and 0.75% essential oil of cinnamon postponed growth on the third day. At 8 °C, Nisin, the cinnamon essential oil alone and in combination (similar to 4 ºC) until the sixth day prevented bacterial growth. Compared to the control treatment, the concentration of Nisin and cinnamon essential oil had a significant difference in inhibitory bacterial growth (P<0.05). The results also showed that the combination of Nisin and cinnamon essential oil, had a significantly higher effect than their single state. Conclusions: Results indicate that Nisin and cinnamon essential oil effectively inhibit the growth of Lactococcus garvieae in the rainbow trout fillet.
Afficher plus [+] Moins [-]Effects of temperature and storage time on pin pull-out testing in harvested canine femurs.
1995
Huss B.T. | Anderson M.A. | Wagner Mann C.C. | Payne J.T.
Effects of temperature and storage time on canine bone-transfixation pin specimens were tested by comparing pin pull-out forces. A total of 16 femurs from 8 mature dogs were tested. Five nonthreaded Steinmann pins were placed through both cortices in the diaphysis of each femur. The femurs were then sectioned transversely between each pin, with a bonepin specimen placed evenly into each of 5 groups prior to biomechanical testing. Four bone-pin specimen groups were stored at -20 or -70 C for 14 or 28 days, while 1 specimen group was immediately tested. Pull-out forces for frozen groups were compared with pull-out forces for the fresh group. Using two-way ANOVA, there was no statistical difference in mean axial-extraction forces among bonepin specimen in any of the tested groups. It is concluded that acute pin pull-out forces are not significantly affected by freezing temperature or time. However, specimens stored at -20 C for as few as 14 days had a trend for increased pull-out forces, compared with freshly harvested specimens. Therefore, the authors recommend storage of bone-pin specimens at -70 C when possible.
Afficher plus [+] Moins [-]Repeated physical and cytologic characterizations of subcutaneous postvaccinal reactions in cats.
1997
Schultze A.E. | Frank L.A. | Hahn K.A.
A study on characteristics of acid-base balance in goats.
1985
Yang I.S. | Sung H.K.
The changes of acid-base status in vitro of the venous blood for 24 hrs in ten Korean native goats were investigated. The acid-base parameters were measured within ten minutes after collection of the blood, and every hour during the first six hours and finally after twenty-four hours of storage. Blood samples were stored at two different temperatures (0-4 deg C and 21-24 deg C). Twelve goats were induced acute acid-base disturbances by intravenous infusion of either hydrochloric acid or sodium bicarbonate and inhalated with CO2 gas mixture (20% C02, 80% O2) or hyperventilation were performed by means of respirator.
Afficher plus [+] Moins [-]First report of the presence of enterotoxin gene in coagulase-negative staphylococci recovered from meat of snails (Achatina achatina)
2022
Okafor, Arthur C. | Ogbo, Frank C. | Akharaiyi, Fred C. | Oladeinde, Henry B.
It has been suggested that coagulase-negative staphylococci can serve as reservoirs of virulence genes for other bacteria. This study assessed the presence of such genes in selected isolates recovered from meat of the giant African snail (Achatina achatina). Virulence genes were detected using a polymerase chain reaction targeting specific primers. Two representative isolates were identified using 16S rRNA gene sequencing. The results showed that the staphylococcal enterotoxin A gene (sea) was present in five out of the eight isolates studied. The isolates expressed resistance mainly to three antibiotics: chloramphenicol, norfloxacin and cloxacillin in descending order of incidence. Most importantly, the Staphylococcus sciuri isolate NEDU 181, in addition to being resistant to the three aforementioned antibiotics, also harboured the sea gene. Our findings demonstrate, for the first time, the presence of toxigenic and antibiotic-resistant coagulase-negative Staphylococcus spp. in commercially-available fresh snail meat. With staphylococcal enterotoxin A known to survive cooking temperature, this presents a food safety concern.
Afficher plus [+] Moins [-]Malignant catarrhal fever in cattle in the Irkutsk Region
2020
Zakharova, Olga | Toropova, Nadezhda | Burova, Olga | Titov, Ilya | Meltsov, Ivan | Blokhin, Andrey
Malignant catarrhal fever (MCF) is a rare, under-explored lethal viral infection of cattle with gammaherpesvirus aetiological agents. Most often, the disease occurs on farms where cattle and sheep are kept together. However, other trigger mechanisms and environmental factors contribute. This study investigates the causation of MCF. An outbreak of MCF occurred in June - August 2017 in Kharchev village in Irkutsk Oblast, Russia. In this paper, we provide epidemiological (sanitary status of pastures, watering places, and premises) and weather data during the outbreak, and descriptions of the clinical signs and post-mortem changes in cattle. The virus was detected and isolated from pathological material samples and identified by molecular methods. Extreme weather conditions, mixed-herd cattle and sheep farming, and unsatisfactory feed quality contributed to the outbreak. A virus related to herpesvirus OvHV2 was isolated and typed (MCF/Irkutsk/2017). Phylogenetic analysis showed its close genetic relationship to isolates from cattle and sheep in Germany, USA, and the Netherlands. Sporadic outbreaks of MCF caused by biotic and abiotic factors together are typical for the Russian Federation, and the Irkutsk outbreak epitomised this. Temperature anomalies caused pasture depletion, resulting in feed and water deficiency for grazing animals and dehydration and acidosis. Heat stress in animals ultimately led to the occurrence of MCF in the herd.
Afficher plus [+] Moins [-]Elaboration of triplex PCR for detection of selected viral infections in waterfowl
2019
Kozdruń, Wojciech | Czekaj, Hanna | Styś-Fijoł, Natalia | Piekarska, Karolina | Samanta Niczyporuk, Jowita
Viral infections are the greatest threat to waterfowl and cause significant economic losses. Diagnosis and differentiation of three goose viruses is difficult in the field and often requires laboratory confirmation. Therefore, the aim of the study was to develop a triplex PCR and optimise its parameters for simultaneous detection of DNA of goose parvovirus (GPV), goose polyomavirus (GHPV), and goose circovirus (GoCV). The DNA of viruses isolated from field cases from the National Veterinary Research Institute’s own collection was used for the study. The primer attachment temperature, the number of reaction cycles, and the Taq DNA polymerase and Mg²⁺ concentrations were optimised. The sensitivity and specificity of this triplex PCR was also determined. Based on the obtained results, triplex PCR parameters were optimised for simultaneous detection of DNA of GPV, GHPV, and GoCV in one sample. The following PCR products of the expected size were obtained: GPV DNA of 806 bp, GoCV DNA of 571 bp, and GHPV DNA of 180 bp. The developed triplex PCR method proved to be useful for simultaneous detection of infections with three waterfowl viruses and will be used in relevant laboratory diagnostics.
Afficher plus [+] Moins [-]Effects of polymyxin B on clinical signs, serum TNF-α, haptoglobin and plasma lactate concentrations in experimental endotoxaemia in sheep
2018
Hajimohammadi, Ali | Badiei, Khalil | Kheibari, Parviz | Pourjafar, Meherdad | Chalmeh, Aliasghar
The experiment evaluated the effects of intravenous administration of polymyxin B on experimental endotoxaemia in sheep. Twenty clinically healthy fat-tailed sheep were randomly divided into: a group treated with 6,000 U/kg of polymyxin B, a group at 12,000 U/kg, and positive and negative controls. Endotoxaemia was induced by intravenous administration of lipopolysaccharide (LPS) from E. coli serotype O55:B5 at 0.5 μg/kg. polymyxin was infused intravenously along with 2.5 L of isotonic intravenous fluids at 20 mL/kg/h. The positive control group received LPS and 2.5 L of isotonic fluids, the negatives receiving just 2.5 L of isotonic fluids. Clinical signs were evaluated before and at 1.5, 3, 4.5, 6, 24, and 48 h after LPS administration. Blood was also sampled at the denoted hours and serum haptoglobin, tumour necrosis factor-α (TNF-α), and plasma lactate concentrations were assayed. The serum concentration of TNF-α in the positive control group increased significantly up to 48 h after LPS administration. The concentration of TNF-α was significantly different from those of the polymyxin B and positive control groups from 3 to 48 h; also, the concentrations of haptoglobin at different times in the polymyxin groups were lower than those of the positive control group and were significant at hours 3 to 48 (P < 0.05). Following the LPS administration, haptoglobin and TNF-α concentrations changed without significant difference between the two polymyxin B groups. Polymyxin B (6,000 U/kg) restrained blood lactate concentrations. Furthermore, it significantly improved the clinical signs in endotoxaemic animals, including rectal temperature and heart and respiratory rates. Polymyxin B may be an antiendotoxic in fat-tailed sheep.
Afficher plus [+] Moins [-]Cell-mediated and humoral immune responses to bovine herpesvirus type 1 and bovine viral diarrhea virus in calves following administration of a killed-virus vaccine and bovine herpesvirus type 1 challenge
2018
Van Anne, Travis R. | Rinehart, Carol L. | Buterbaugh, Robin E. | Bauer, Matt J. | Young, Alan J. | Blaha, Michelle L. | Klein, Angela L. | Chase, Christopher C. L.
OBJECTIVE To evaluate cell-mediated and humoral immune responses of calves receiving 2 doses of a dual-adjuvanted vaccine containing inactivated bovine herpesvirus type 1 (BHV1) and bovine viral diarrhea virus types 1 (BVDV1) and 2 (BVDV2) before and after exposure to BHV1. ANIMALS 24 Holstein steers negative for anti-BHV1 antibodies and proliferative cell-mediated immune responses against BHV1 and BVDV. PROCEDURES Calves were randomly assigned to 3 groups. The vaccinated group (n = 10) received 2 doses of vaccine on days 0 and 21. Control (n = 10) and seeder (4) groups remained unvaccinated. Calves were commingled during the study except for the 3-day period (days 53 to 55) when seeders were inoculated with BHV1 (1.04 × 107 TCID50, IV) to serve as a source of virus for challenge (days 56 through 84). Rectal temperature and clinical illness scores were monitored, and blood and nasal specimens were obtained for determination of clinicopathologic and immunologic variables. RESULTS After BHV1 challenge, mean rectal temperature and clinical illness scores were lower for vaccinates than controls. In vaccinates, antibody titers against BHV1 and BVDV2, but not BVDV1, increased after challenge as did extracellular and intracellular interferon-γ expression, indicating a T helper 1 memory response. Additional results of cell marker expression were variable, with no significant increase or decrease associated with treatment. CONCLUSIONS AND CLINICAL RELEVANCE Calves administered 2 doses of a killed-virus vaccine developed cell-mediated and humoral immune responses to BHV1 and BVDV, which were protective against disease when those calves were subsequently exposed to BHV1.
Afficher plus [+] Moins [-]Use of plethysmographic variability index and perfusion index to evaluate changes in arterial blood pressure in anesthetized tigers (Panthera tigris)
2018
Smith, Christopher K. | Seddighi, Reza | Zhu, Xiaojuan | Tepe, Andrew J. | Ramsay, Edward C. | Cushing, Andrew C.
OBJECTIVE To investigate use of the plethysmographic variability index (PVI) and perfusion index (PI) for evaluating changes in arterial blood pressure in anesthetized tigers (Panthera tigris). ANIMALS 8 adult tigers. PROCEDURES Each tiger was anesthetized once with a combination of ketamine, midazolam, medetomidine, and isoflurane. Anesthetic monitoring included assessment of PI, PVI, direct blood pressure measurements, anesthetic gas concentrations, esophageal temperature, and results of capnography and ECG. Mean arterial blood pressure (MAP) was maintained for at least 20 minutes at each of the following blood pressure conditions: hypotensive (MAP = 50 ± 5 mm Hg), normotensive (MAP = 70 ± 5 mm Hg), and hypertensive (MAP = 90 ± 5 mm Hg). Arterial blood gas analysis was performed at the beginning of anesthesia and at each blood pressure condition. RESULTS Mean ± SD PI values were 1.82 ± 2.38%, 1.17 ± 0.77%, and 1.71 ± 1.51% and mean PVI values were 16.00 ± 5.07%, 10.44 ± 3.55%, and 8.17 ± 3.49% for hypotensive, normotensive, and hypertensive conditions, respectively. The PI values did not differ significantly among blood pressure conditions. The PVI value for the hypotensive condition differed significantly from values for the normotensive and hypertensive conditions. The PVI values were significantly correlated with MAP (r = −0.657). The OR of hypotension to nonhypotension for PVI values ≥ 18% was 43.6. CONCLUSIONS AND CLINICAL RELEVANCE PVI was a clinically applicable variable determined by use of noninvasive methods in anesthetized tigers. Values of PVI ≥ 18% may indicate hypotension.
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