Effects of feeding calves genetically modified corn bt11: a clinico-biochemical study

Genetically modified corn Bt11 is insect-resistant and expresses Cry1Ab toxin, an insecticidal protein, in kernels. Although Bt11 corn is considered safe based on animal performance, there are no reports available on the clinico-biochemical effects of feeding it to cattle. In this study, we evaluated the effects of feeding Bt11 to calves, using blood and ruminal clinico-biochemical parameters. Our three-month-long feeding experiment demonstrated that calves (n=6), fed with a ration containing 43.3% of Bt11 corn kernels as dry matter, did not develop any discernible clinical, hematological, biochemical, or ruminal abnormalities as compared with control calves (n=6) fed non-Bt11 corn. The results suggest that the transgenic Bt11 has no negative clinico-biochemical effects on calves.     

Cloning,expression, and tissue distribution of bovine interleukin-21

Bovine interleukin-21 (IL-21) cDNA was cloned and sequenced from bovine peripheral blood lymphocytes (PBLs) stimulated with 10 microg/ml concanavalin A (ConA), 10 microg/ml phytohemagglutinin (PHA), and 50 ng/ml phorbol 12-myristate 13-acetate (PMA) for 48 h. The open reading frame of the bovine IL-21 cDNA is 459 bp in length and encodes 152 amino acids. The predicted amino acid sequence is 78.2 and 58.5% homologous to the human and murine IL-21 amino acid sequences, respectively. Recombinant bovine IL-21 was expressed by a baculovirus expression system. The bovine IL-21 was processed to the mature form in insect cells and secreted to the supernatant confirmed by N-terminal amino acid sequencing. The recombinant bovine mature IL-21 induced the proliferation of human IL-2-dependent cells, ILT-MAT. The mRNA expression for bovine IL-21 was observed in the spleen, but not in the brain, heart, lung, liver, and kidney. The bovine IL-21 identified in this study may provide new methods for the enhancement of innate immunity in cows.     

Cytotoxic T-lymphocyte activity specific for hemagglutinin (H) protein of canine distemper virus in dogs

Cytotoxic T-lymphocyte (CTL) responses to hemagglutinin (H) protein of canine distemper virus (CDV) were evaluated in dogs using the replication-deficient adenovirus protein expression system. Skin fibroblasts were isolated from two dogs and were infected with recombinant adenovirus bearing the CDV-H gene (Ade-CDVH). CTL assay was performed using fibroblasts expressing CDV-H protein as target cells and peripheral blood lymphocytes (PBL) collected from the same dogs one week after immunization of CDV as effector cells. Specific cytotoxic activity was observed against autologous but not heterologous fibroblasts expressing CDV-H protein. These results indicate that the CTL epitope(s) were localized in the H protein.     

Ganglioglioma in the thalamus of a puppy

A solitary brain mass of a 4-month-old miniature dachshund showing seizure-like neurological signs was examined histopathologically. At necropsy a white tumor mass, replacing the thalamus, approximately 1.5 cm in diameter, was found. There was cystic space filled with yellowish pale fluid in the central area of the tumor mass. Histopathological examination revealed that the mass consisted of irregularly arranged well-differentiated neuronal and glial cells, and multifocal mineral deposits. The neuronal cells had a large clear nucleus and various amount of Nissl substances in the cytoplasm. Some neural cells were bi-nucleated. Neither mitotic figures nor proliferating cell nuclear antigen (PCNA)-positive nuclei was found in the neuronal cells. Immunostaining for glial fibrillary acidic protein (GFAP) revealed diffuse proliferation of GFAP-positive glial cells and their processes, while these glial cells did not show apparent cellular atypism, mitotic activity, or PCNA-immunoreactivity. Accordingly, the present tumor was diagnosed as ganglioglioma, and hamartomatous histogenesis might be possible.     

Large-scale production of porcine mature interleukin-18 (IL-18) in silkworms using a hybrid baculovirus expression system

In this report, a hybrid baculovirus expression system, which means a hybrid virus of the Autographa californica nuclear polyhedrosis virus and the Bombyx mori nuclear polyhedrosis virus, was used for the large-scale production of porcine mature interleukin-18 (IL-18) in silkworms. Two recombinant hybrid baculoviruses containing cDNA of the porcine precursor IL-18 and the porcine caspase-1 were constructed and were used to infect silkworm larvae. After the co-infection of the two viruses, porcine mature IL-18 was efficiently produced in the haemolymph. The concentration of IL-18 in the haemolymph was 80-100 microg/ml, as determined by porcine IL-18 specific ELISA. This yield was twenty-times more than that of the insect cell expression system described previously. The porcine mature IL-18 produced by the silkworms strongly induced interferon-gamma (IFN-gamma) production from porcine PBMC. An insect factory system for the large-scale production of useful cytokines for livestock animals will be available in the near future.     

Advanced treatment of swine wastewater by electrodialysis with a tubular ion exchange membrane

To remove the excess nitrogen and phosphorus in swine wastewater, an electrodialysis technique was applied to an advanced treatment method. The laboratory‐scale swine wastewater treatment system constructed for the present study consisted of an activated sludge process, as the main treatment unit, and electrodialysis, as an advanced treatment unit. This system was operated for 200 days and the processing performance was evaluated. By electrodialysis, approximately 99% of NO₃^– and PO₄^3– in the activated sludge‐treated water (AT solution) was removed during operation. Furthermore, electrodialysis decreased the color density of the AT solution at a rate of 58%. The advanced treatment of swine wastewater by electrodialysis proved to be an efficient technique to remove excess nitrogen and phosphorus, and decrease color density.     

Changes in hepatic enzyme activities in transgenic mice carrying human prototype c-Ha-ras gene treated with diethylnitrosamine

Activities of malate dehydrogenase (MDH) and aspartate aminotransferase in the malate-aspartate shuttle were significantly increased in the cytosolic fractions of livers with early neoplastic symptoms such as swelling and discoloration in transgenic mice carrying the prototype human c-Ha-ras gene, Tg-rasH2 mice, which were administered with diethylnitrosamine (DEN) as a carcinogenic chemical at a dose of 200 mg/kg body weight. Cytosolic MDH/LDH (lactate dehydrogenase) (ML) ratio increased significantly and was considered to be a useful marker to characterize the energy metabolism at early neoplastic stage in livers of the Tg-rasH2 mice.     

Identification of genes expressed during spore germination of Mycosphaerella pinodes

Mycosphaerella blight, caused by Mycosphaerella pinodes, is one of the major diseases of cultivated pea (Pisum sativum L.). To isolate the genes that are up- and down-regulated during spore germination, suppression subtraction hybridization (SSH) was performed between ungerminated and germinated spores. The 232 and 128 clones from forward and reverse libraries, respectively, were collected, sequenced, and analyzed with a BLASTX homology search. About 95% of the 32 selected clones were expressed during spore germination on a paper sheet and during infection of pea leaves. We discuss the applicability of the SSH libraries for analyzing M. pinodes genes involved in the early stage of infection.     

Transepidermal water loss (TEWL) reflects skin barrier function of dog

The correlation between skin barrier function and transepidermal water loss (TEWL) was evaluated in dogs. Stratum corneum (SC) of 10 healthy dogs was removed by tape stripping (TS), which decreased the corneal layer to allow for permeation of fluorescent dye into skin. TEWL of damaged skin was measured with the closed-chamber-type TEWL analyzer, CC-01. The frequency of TS was directly related to the decrease of SC and the increased permeation of fluorescent dye, and TEWL increased with increasing impairment of skin barrier function. The results suggest that increased TEWL reflects impaired canine skin barrier function.