Plasma and tissue pharmacokinetics of marbofloxacin in experimentally infected chickens with Mycoplasma gallisepticum and Escherichia coli

The plasma and tissue pharmacokinetics of marbofloxacin in chickens experimentally infected with Mycoplasma gallisepticum and Escherichia coli were studied. Marbofloxacin was given to 66 infected chickens by oral administration at a dosage of 5 mg/kg b.w., once a day for three days. Plasma, brain, kidney, liver, lung, muscle and trachea were collected and marbofloxacin concentrations were analyzed by a high performance liquid chromatography method. In the infected chickens, maximal marbofloxacin concentrations in plasma, brain, kidney, liver, lung, muscle and trachea were 1.84, 1.33, 7.35, 5.61, 3.12, 2.98, and 4.51 g/mL (g); the elimination half‐lives of marbofloxacin were 6.8, 2.74, 9.31, 8.45, 9.55, 11.53 and 5.46 h for plasma, brain, kidney, liver, lung, muscle and trachea, respectively. AUC were calculated to be 9.68, 8.04, 45.1, 27.03, 20.56, 19.47, and 32.68 μg/mL (g) ·h for plasma, brain, kidney, liver, lung, muscle and trachea, respectively. Marbofloxacin concentration in tissues except for brain exceeded marbofloxacin concentration in plasma, with AUC_tissue/AUC_plasma ranging from 2.01 to 4.66 and Peak_tissue/Peak_plasma ranging from 1.62 to 3.99. The results showed that a marbofloxacin dosage of 5 mg/kg administered orally at 24 h intervals may provide successful treatment of chicken with MG and E. coli infection.     

Differential expression of peroxisome proliferator-activated receptors alpha and gamma gene in various chicken tissues

The peroxisome proliferator-activated receptors (PPARs) are the members of superfamily of nuclear hormone receptors. A great number of studies in rodent and human have shown that PPARs were involved in the lipids metabolism. The goal of the current study was to investigate the expression pattern of PPAR genes in various tissues of chicken. The tissue samples (heart, liver, spleen, lung, kidney, stomach, intestine, brain, breast muscle and adipose) were collected from six Arber Acres broilers (8 weeks old, male and female birds are half and half). Semi-quantitative RT-PCR and Northern blot were used to characterize the expression of PPAR-alpha and PPAR-gamma genes in the above tissues. By semi-quantitative RT-PCR, the results showed the expression level of PPAR-alpha gene was higher in brain, lung, kidney, heart and intestine, medium in stomach, liver and adipose than in spleen, and it did not express in breast muscle. The expression level of PPAR-gamma gene was higher in adipose, medium in brain and kidney than in spleen, heart, lung, stomach and intestine, but it did not express in liver and breast muscle. Northern blot results showed that PPAR-alpha gene expressed in heart, liver, kidney and stomach, and the intensity of hybridization signal was the stronger in liver and kidney than in other tissues, however, PPAR-gamma gene only expressed in adipose and kidney tissues. The results of this study showed the profile of PPAR gene expression in the chicken was similar to that in rodent, human and pig. However the expression profile of chicken also have its own specific trait, i.e. compared with mammals, PPAR-alpha gene can not be detected in skeletal muscle and PPAR-gamma gene can be stronger expressed in kidney tissues. This work will provide some basic data for the PPAR genes expression and lipids metabolism of birds.     

Pathogenic Effects of Cloned Genomic DNA of Porcine Circovirus-like Virus P1 on Neonatal Mice via Different Inoculation Routes

[Objective] The paper was to explore the pathogenicity of cloned genomic DNA of porcine circovirus-like virus P1 to neonatal mice via different inoculation routes(brain, liver and muscle). [Method] Cloned genomic DNA of P1 was inoculated to neonatal mice via different routes of brain, liver and muscle. Tissues of heart, liver, spleen, lung, kidney and brain were taken from neonatal mice at 7, 14 and 21 d post inoculation, re-spectively. P1 in various tissues were qualitatively and quantitatively detected by using ordinary PCR and quantitative real-time PCR. Meanwhile,histopathological changes were analyzed. [Result] P1 was detected in neonatal mice inoculated through three different routes. The viral load of tis-sues at 7 d post inoculation was significantly higher than those at 14 and 21 d post inoculation. Moreover, muscle inoculation led to the highest vi-ral load in all tissues of neonatal mice. [Conclusion] P1 infection caused different degrees of pathological damage to heart, liver, lung, kidney and brain in neonatal mice.     

Evidence for the vertical transmission of Sunshine virus

Sunshine virus is a paramyxovirus of pythons associated with neurorespiratory disease and mortalities. This report provides evidence for its vertical transmission. In a collection of over 200 Australian pythons, a dam and a sire, both carpet pythons (Morelia spilota), were PCR-positive for Sunshine virus at a time when the dam was likely to have been gravid. A clutch of 21 eggs was laid and three non-viable eggs were tested for the presence of Sunshine virus by PCR. One egg had been incubating for 34 days while the other two had been incubating for 49 days. The surface of all three eggs was negative for Sunshine virus but swabs of the allantois and amnion were positive in all three eggs. Embryo tissue samples were tested from the two 49 day old eggs. From one embryo, a sample of brain and a pooled sample of lung, liver, kidney and intestine were positive, while for the other embryo, a pooled sample of lung, liver, kidney, intestine and brain was positive. Fourteen of the 21 eggs hatched and all hatchlings were tested by PCR at least once between the ages of 53 and 229 days old. All hatchlings were PCR-negative for Sunshine virus.     

Reference gene screening for analyzing gene expression in the heart,liver, spleen,lung and kidney of forest musk deer

The screening of reference genes for real-time quantitative PCR (qPCR) in forest musk deer (FMD) tissue is of great significance to the basic research on FMD. However, there are few reports on the stability analysis of FMD reference genes so far. In this study, We used qPCR to detect the expression levels of 11 reference gene candidates (18S rRNA, beta-actin [ACTB], glyceraldehyde-3-phosphate dehydrogenase [GAPDH], TATA box-binding protein [TBP], hypoxanthine phosphoribosyltransferase 1 [HPRT1], tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta polypeptide [YWHAZ], hydroxymethylbilane synthase [HMBS], eukaryotic translation elongation factor 1 alpha 1 [EEF1A1], succinate dehydrogenase complex flavoprotein subunit A [SDHA], peptidylprolyl isomerase B [PPIB], and ubiquitin C [UBC]) in heart, liver, spleen, lung and kidney of FMD. After removing 18S rRNA on account of its high expression level, geNorm, NormFinder, BestKeeper and ΔCt algorithms were used to evaluate the expression stability of the remaining genes in the five organs, and further comprehensive ranking was calculated by RefFinder. According to the results, the selected reference genes with the most stable expression in the heart of FMD are SDHA and YWHAZ, while in the liver are ACTB and SDHA; in the spleen and lung are YWHAZ and HPRT1; in the kidney are YWHAZ and PPIB. The use of common reference genes in all five organs is not recommended. The analyses showed that tissue is an important variability factor in genes expression stability. Meanwhile, the result can be used as a reference for the selection of reference genes for qPCR in further study.     

Epidemiology, pathology, and immunohistochemistry of layer hens naturally affected with H5N1 highly pathogenic avian influenza in Japan

Epidemiology, pathology, and immunohistochemistry were investigated in layer hens affected with H5N1 highly pathogenic avian influenza, which occurred for the first time in 79 years in Japan. The farm, which had a total of 34,640 chickens, experienced up to 43.3% mortality before the chickens were depopulated. Clinically, the affected chickens exhibited mortality without apparent clinical signs. Histologically, hepatocytic necrosis; necrosis of ellipsoids and follicles with fibrin in the spleen; necrosis with glial nodules in the brain stem, cerebrum, and cerebellum; necrosis of acinar cells in the pancreas; and necrosis of lymphoid tissues in intestinal lamina propria were seen. Occasionally, mild bronchiolitis, degeneration of smooth muscle fibers in the cecum, and mild tubulonephrosis were noted. Immunohistochemically, influenza virus antigens were detected often in the liver and spleen, heart, intestine, gizzard, proventriculus, and oviduct. In addition, antigens were seen also in the brain, kidney, pancreas, and ovary, but seldom in the lung and trachea. Virus antigen was mainly detected in the capillary endothelium and parenchymal cells. This suggests that virus excretion from the respiratory tract was not as prevalent as that from the digestive tract in the present cases.     

重组鸡痘病毒vFV282疫苗株在鸽体内的分布及毒性试验

采用翅内侧皮肤无血管处刺种途径给30日龄幼鸽接种重组鸡痘病毒vFV282疫苗株,利用PCR的方法检测其在鸽体内的分布及其动态并对其毒性进行了研究。结果显示,接种后6 h即在脾脏检测到病毒DNA;接种后1 d,脾、肺PCR检测阳性;3 d,在心、肝、脾、肺、肾、皮肤均检测到病毒DNA;7 d,心、肝、脾、肺、肾、脑PCR检测均呈阳性;10 d,除脑外所有内脏器官中均未检测到病毒DNA,15 d后所有内脏器官PCR检测结果均为阴性。而对照组在整个试验期间PCR检测结果均为阴性。毒性试验表明,重组鸡痘病毒vFV282疫苗株使用安全。     

Studies on Transmissible Gastroenteritis of Swine I. The Isolation and Identification of a Cytopathogenic Virus of Transmissible Gastroenteritis in Primary Swine Kidney Cell Cultures

Two virus isolates from transmissible gastroenteritis (TGE) of swine were adapted to grow in primary swine kidney cells. Growth of the virus was indicated by the resistance of the infected cells to the cytopathic effect of a virus diarrhea virus of cattle, and by the development of large round cells on the cell sheet.

Evidence that these virus isolates were TGE was obtained by the development of signs of the disease followed by death of exposed SPF pigs, or the resistance of the recovered pigs to further signs of disease when they were exposed to virulent TGE contained in virus bearing intestinal tissue.

The in vitro and in vivo serum neutralization tests, along with staining of infected cells by fluorescein conjugated TGE antiserum, gave further indication of the specific nature of the virus growing in the cell cultures.

     

Concurrent vaccination of goats with foot and mouth disease (FMD) and peste des petits ruminants (PPR) booster vaccines

Foot and mouth disease (FMD) remains subclinical and self-limiting in small ruminants, but risk of spread of infection to susceptible cohorts is of great epidemiological significance; therefore, small ruminants must be included in vaccination campaigns in FMD endemic regions. Three groups of goats already immunized against peste des petits ruminants (PPR) were vaccinated with FMD and PPR vaccines alone or concurrently. The specific antibody response against three FMD virus strains and PPR virus were evaluated by competitive enzyme-linked immunosorbent assay (cELISA). Goats concurrently vaccinated with PPR + FMD vaccines had significantly (p < 0.05) higher antibody titers to two serotypes of FMD virus at 28, 45, and 60 days post-immunization compared to goats vaccinated with FMD vaccine alone, while goats vaccinated with PPR vaccines alone or PPR + FMD vaccines concurrently showed similar antibody kinetics against PPR virus up till 60 days post-vaccination. Overall, antibody kinetic curves for all three tested strains of FMD virus and PPR virus were similar in vaccinated groups during the course of experiment.     

Biological properties of waterfowl-origin type A influenza viruses in chickens.

The replicative abilities and tissue tropism properties of 13 non-pathogenic or low-pathogenic waterfowl-origin type A influenza isolates recovered in 1986 were examined in chickens. Following intravenous challenge, reisolation of challenge virus was attempted from swabs of the luminal surfaces of the cloaca, jejunum, ileum, bursa, trachea, and air sacs and from swabs of bone marrow and liver tissues. Virus-isolation attempts were also accomplished on brain, thymus, spleen, pancreas, gonad, kidney, blood, and lung tissues. The overall frequency of influenza virus recovery for each experiment ranged from 3.1% to 49.3%. For all experiments combined, 58.3% of the kidney tissues and 62.9% of the cloacal swab samples collected on days 1 to 10 postinoculation were positive for challenge virus recovery. Virus titers up to 10(8.7) mean embryo infective dose per gram of kidney tissue were demonstrated in clinically normal chickens. Distinct biological variations and nephrotropism appear to exist among the corporate properties of virus populations making up each of the 13 waterfowl-origin type A influenza isolates.     

Susceptibility of cats, sheep, and swine to a rabbit isolate of Encephalitozoon cuniculi

Newborn cats, pigs, and sheep (3 to 14 days old) and postweanling cats (2.5 months old) that had been inoculated with Gardner feline sarcoma virus and feline leukemia virus at 10 days of age were infected experimentally with a rabbit isolate of the mammalian protozoan parasite Encephalitozoon cuniculi. Infection occurred in all cats and in some sheep, but was questionable in pigs. Brain and kidney were the 2 major target organs in cats. The lesions were compatible with, but less severe than, those of naturally infected cats and other carnivores. Of 13 cats, E cuniculi could be detected morphologically in the kidneys of 12 cats and in the brain of 1 cat. The organisms were reisolated from 2 cats with ground tissue suspension of kidney or urine sediment. The indirect immunofluorescence antibody (IFA) titers were 1:20 to 1:1,280 at the time the animals were killed, but antibodies were not detected before inoculation. Lesions were seen in the kidneys of 2 of 4 sheep. These lesions were mild, but were compatible with those in a spontaneously affected goat. Encephalitozoon cuniculi were found morphologically in the kidney of 1 sheep with lesions. All sheep had IFA titers of 1:10 to 1:20 before inoculation, and the titers were 1:20 to 1:320 when they were killed. Vasculitis, similar to the subacute-to-chronic stage of polyarteritis nodosa, was observed in 1 of 8 pigs. The lesions were primarily present in the kidney; comparable but milder lesions were also seen in the heart and brain. Antibody was not detected before inoculation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Total radioactive residues and clenbuterol residues in swine after dietary administration of [14C]clenbuterol for seven days and preslaughter withdrawal periods of zero, three, or seven days

Nine barrows (23.8 +/- 0.9 kg) and 9 gilts (23.1 +/- 0.9 kg) were used to determine the disposition of radiocarbon after oral [14C]clenbuterol (4-amino-alpha-[t-butylaminomethyl]-3,5-dichlorobenzyl [7-(14)C]alcohol hydrochloride) administration and to determine total and parent residues in edible tissues. Three barrows and three gilts, housed in metabolism crates, were fed 1 ppm [14C]clenbuterol HCl for seven consecutive days in three separate trials; a single barrow and gilt from each trial was slaughtered after 0-, 3-, or 7-d preslaughter withdrawal periods. Urine and feces were collected during the dosing and the withdrawal period; edible and inedible tissues were collected at slaughter. Total recovery of radiocarbon was 94.2 +/- 6.5%. Total clenbuterol absorption was greater than 75% for barrows and 60% for gilts. Total radioactive residues in tissues were not different (P > 0.05) between barrows and gilts. Concentrations of parent clenbuterol in liver, kidney, skeletal muscle, adipose tissue, and lung did not differ between barrows and gilts (P > 0.05). Total radioactive and parent residues declined in tissues as withdrawal period increased. After the 0-d withdrawal period, total liver residues (286 ppb) were approximately equal to lung residues, twice those of the kidney, and about 15 times those of adipose tissue and skeletal muscle. After a 7-d withdrawal period, total radioactive residues in liver (15 ppb) were roughly three times greater than lung, kidney, and adipose tissue total residues and about 13 times those of skeletal muscle total residues. Parent clenbuterol represented 79, 63, 42, 67, and 100% of the total radioactive residue in adipose tissue, kidney, liver, lung, and skeletal muscle, respectively, in hogs slaughtered with a 0-d withdrawal period. With increasing withdrawal period, the percentage of total radioactive residue present as parent clenbuterol within edible tissues (including lung) decreased, so that after a 7-d withdrawal period, 7, 16, and 29% of the total residue was composed of parent clenbuterol in kidney, liver, and lung, respectively. After a 7-d withdrawal period, parent clenbuterol exceeded the European maximum residue limit (0.5 ppb) 4.6-fold in liver and 2.4-fold in lung. In muscle, clenbuterol was approximately 40 times the limit after a 0-d withdrawal period but had dropped below 0.5 ppb after a 3-d withdrawal period. Results from this study indicate that clenbuterol HCl is well absorbed in swine and that the use of clenbuterol in this species in an off-label manner is inconsistent with human food safety standards used in developed countries.     

Alkaline phosphatase and its isoenzymes in the tissues and sera of normal dogs

The total alkaline phosphatase (AP) activity and the pattern of its isoenzymes were studied in the tissues and sera of normal adult dogs. Small intestine mucosa showed the greatest total AP activity followed by kidney, bone, pancreas, liver, lung, skeletal muscle and heart muscle. After separation by agarose gel electrophoresis, each tissue showed only one isoenzyme except lung which showed two. The tissue isoenzymes, in decreasing order of migration distance towards the anode, were as follows: fast lung isoenzyme, liver or slow lung isoenzyme, the group consisting of skeletal muscle, bone, small intestine and pancreas isoenzymes and, finally, the kidney isoenzyme. Two isoenzymes occurred in serum. The major band corresponded to liver and the slow lung isoenzyme, while the minor band was considered to be the corticosteroid-induced isoenzyme, previously thought to be absent from normal serum.The AP isoenzyme patterns in lung and skeletal muscle and the presence of an isoenzyme migrating an identical distance to the corticosteroid-induced isoenzyme do not appear to have been reported before in normal dogs.     

Alkaline phosphatase and its isoenzymes in the tissues and sera of normal dogs

The total alkaline phosphatase (AP) activity and the pattern of its isoenzymes were studied in the tissues and sera of normal adult dogs. Small intestine mucosa showed the greatest total AP activity followed by kidney, bone, pancreas, liver, lung, skeletal muscle and heart muscle. After separation by agarose gel electrophoresis, each tissue showed only one isoenzyme except lung which showed two. The tissue isoenzymes, in decreasing order of migration distance towards the anode, were as follows: fast lung isoenzyme, liver or slow lung isoenzyme, the group consisting of skeletal muscle, bone, small intestine and pancreas isoenzymes and, finally, the kidney isoenzyme. Two isoenzymes occurred in serum. The major band corresponded to liver and the slow lung isoenzyme, while the minor band was considered to be the corticosteroid-induced isoenzyme, previously thought to be absent from normal serum. The AP isoenzyme patterns in lung and skeletal muscle and the presence of an isoenzyme migrating an identical distance to the corticosteroid-induced isoenzyme do not appear to have been reported before in normal dogs.     

The Expression Characteristics of MYNN Gene in Different Tissues and Muscles of Pig

This study was aimed to investigate the expression characteristics of myoneurin (MYNN) gene in different tissues and its developmental expression in muscles (longissimus dorsi, biceps femoris and psoas major), cerebellum, liver, pancreas, kidney, stomach, spleen and lung tissues of pigs. The expression characteristics of MYNN mRNA in 11 different tissues including heart, liver, spleen, lung, kidney, cerebellum, small intestine, pancreas, stomach, biceps femoris and fat of Large White pigs and Mashen pigs at the age of 90 days and the developmental expression patterns in muscle, cerebellum, liver, pancreas, kidney, stomach, spleen at three strages (1, 90, 180 days) of Large White pigs and Mashen pigs were studied by Real-time PCR. The results showed that MYNN was widely expressed in various tissues of pigs, and there was significant difference among the tissues(P < 0.05; P < 0.01); The expression of MYNN in muscle, liver, pancreas, cerebellum, kidney, stomach, spleen, lung tissues were significant difference at three development stages of Large White pigs and Mashen pigs(P < 0.05; P < 0.01), and also had a specific rule, which indicated that it may play an important role in these pig tissues. The expression of MYNN gene could related to the tissue, age and the genetic background of breeds. The results of this study provided a better understanding of the biological functions of pig MYNN. Further studies are required to determine its molecular mechanisms, especially in the regulation of skeletal muscle development.