Geographical variation in the skeletal morphology of red jungle fowl

1. The skulls and postcranial skeletons of the red jungle fowl (Gallus gallus) were compared osteometrically between the populations from North and South Vietnam, North and Central Laos and Southeast Bangladesh. The populations include the three subspecies of G. g. spadiceus, G. g. gallus and G. g. murghi and were sampled to reveal the geographical morphological variations among populations in G. gallus.

2. The morphometric characteristics of subspecies murghi could be clearly distinguished from those of the other subspecies using a canonical discriminant analysis. However, the size and shape of the skull of the gallus population from South Vietnam were not statistically different from that of the subspecies spadiceus from North Laos. The canonical discriminant scores also clearly indicated that there were morphological similarities in the skulls of the populations from North Laos and South Vietnam.

3. From the results, therefore, it is concluded that red jungle fowls do not exhibit high levels of osteometric variation between geographical localities at least within the Indochinese Peninsula.

4. This contrasts with previous studies which have described these subspecies as having various external morphological differences and have argued that zoogeographical barriers exist between the north and south areas of the Indochinese Peninsula.     

Hereditary high-potassium erythrocytes with high Na, K-ATPase activity in Japanese shiba dogs.

The sodium (Na) and potassium (K) concentrations and Na, K-ATPase activity were examined in erythrocytes from 24 Japanese shiba dogs and 79 dogs of 24 other breeds. Eleven of the shibas had erythrocytes with high K and low Na concentrations, together with high Na, K-ATPase activity (HK RBCs), while red cells from the remaining shibas and all of the other breeds examined showed low K and high Na concentrations, with no enzyme activity (LK RBCs). The concentration of reduced glutathione in HK RBCs was about five times that in LK RBCs. All the findings from HK shibas were in good agreement with those from HK mongrel dogs found in Japan previously. Since the shiba is a Japanese breed of dog, the results of the present study strongly suggest that the gene for HK RBCs may be inherent in dogs indigenous to Japan, particularly in shiba dogs.     

Variety in histochemical characteristics of the olfactory receptor cells in a flatfish, barfin flounder (Verasper moseri)

Variety in histochemical characteristics of the olfactory receptor cells (ORC) was examined by immunohistochemistry for protein gene product 9.5 (PGP9.5) and calretinin, and by lectin histochemistry with Phaseolus vulgaris leucoagglutinin (PHA-L) in the olfactory epithelium (OE) of the barfin flounder (Verasper moseri). PGP 9.5 immunoreactivity was observed in the ORC situated in the upper three fourths of the OE. Calretinin immunoreactivity was observed in the ORC which seemed to be immunonegative for PGP 9.5. These cells were located in the upper two thirds of the OE. PHA-L staining was observed in small subsets of the ORC. PGP 9.5 and calretinin immunoreactivities and PHA-L staining were also observed in the crypt cells unique to the fish OE. These findings suggest the different properties of olfactory perception among fish ORC.     

Morphogenesis of the olfactory pit in a flatfish, barfin flounder (Verasper moseri)

Morphogenesis of the olfactory pit (OP), olfactory lamella (OL) and olfactory epithelium (OE) was examined by scanning electron and light microscopy in the barfin flounder (Verasper moseri). At day 0 after hatch, the OP was already formed. At day 14, the cellular differentiation of the OE was prominent. At day 42, the OP became a cavity by the formation of its roof. At day 56, the first OL extended remarkably and was lined with the OE on both sides. The OL increased in number with development. These findings suggest that the OE is functionally active at day 14. The formation of the OL in the OP may be initiated by the stimulus when the barfin flounder touched at the bottom of the sea.     

Cryoglobulinemia in a horse.

Cryoglobulin was isolated from a horse which had glomerulo-nephritis and a history of swelling and skin ulcers of the limbs in the winter. The isolated cryoglobulin showed a single peak on a gel permeation chromatography column with an apparent molecular mass (Mr) of 180,000 which could be divided into two gamma bands by cellulose acetate electrophoresis. Immunoelectrophoretic analysis revealed that the cryoglobulin formed two precipitation lines with anti-horse IgG. Spur formation was observed when the cryoglobulin and the IgG purified from a normal healthy horse were cross-reacted with anti-horse IgG on a double diffusion gel. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis under the reduced conditions showed that the isolated cryoglobulin consisted of two doublets of polypeptides with Mr values of 52,000 and 50,000, and 31,000, and 30,000, corresponding to the heavy chain and the light chain of the horse IgG molecules, respectively. These results suggest that the isolated cryoglobulin might consist of two different IgG molecules, and that the manifestations such as foot swelling with skin ulcers and renal failures were all induced by the cryoglobulin in the serum.     

Occurrence and molecular characterization of strobilurin resistance in cucumber powdery mildew and downy mildew

ABSTRACT Between 1998 and 1999, control failure of powdery mildew (Podosphaera fusca) and downy mildew (Pseudoperonospora cubensis) by the strobilurin fungicides azoxystrobin and kresoxim-methyl was observed in cucumber-growing areas of Japan. Results from inoculation tests carried out on intact cucumber plants and leaf disks clearly showed the distribution of pathogen isolates highly resistant to azoxystrobin and kresoximmethyl. Fragments of the fungicide-targeted mitochondrial cytochrome b gene were polymerase chain reaction amplified from total pathogen DNA and their sequences analyzed to elucidate the molecular mechanism of resistance. A single point mutation (GGT to GCT) in the cytochrome b gene, resulting in substitution of glycine by alanine at position 143, was found in resistant isolates of downy mildew. This substitution in cytochrome b seemed to result in high resistance to strobilurins in this pathogen. The same mutation was found in some but not all resistant isolates of powdery mildew. This study suggests that a mutation at position 143 in the target-encoding gene, resulting in an amino acid substitution, was probably a major cause of the rapid development of high strobilurin resistance in these two pathogens.     

Chromatographic and immunological identification of gonadotropin-releasing hormone in five marine teleosts

Brain extracts from bluefin tuna, Thunnus thynnus, red seabream, Pagrus major, black seabream, Acanthopagrus schlegeli, red spotted grouper, Epinephelus akaara and Japanese flounder, Paralichthys olivaceus, were analyzed by high performance liquid chromatography (HPLC) and specific radioimmunoassays. Immunoreactive material co-eluting from HPLC with salmon gonadotropin-releasing hormone (GnRH) and chicken GnRH-II, respectively, was found in all five species. In addition, a GnRH immunoreactive fraction showing the same HPLC retention time as lamprey GnRH-I was detected in the brain extracts of all species examined when using an unspecific radioimmunoassay which detects several GnRH forms, including lamprey GnRH-I. In the Japanese flounder brain extract, a fourth GnRH immunoreactive fraction was detected with the unspecific radioimmunoassay which did not co-elute with any of the six synthetic GnRH standards used in the present study.     

Self-feeding activity of a pleuronectiform fish, the barfin flounder

The self-feeding activity of the barfin flounder (Verasper moseri) was examined under natural photoperiod and temperature. The experiment, carried out over 12 weeks from September to December, involved tagged fish (mean body weight: 371 g) reared in three 1000-l tanks (3 or 5 fish per tank) with a self-feeder device. The sensor comprised a switch and trigger string with a bead. Self-feeding activity was recorded in all tanks from day 1. The fish fed mostly at night. Strong positive correlations were observed between the number of daily feeder activations and water temperature/photoperiod, and all fish grew during the experiment. These results demonstrate that barfin flounder can operate self-feeding systems and it is suggested that self-feeding activity is influenced by photoperiod and water temperature.