Relationship between ovarian weight and follicular population in heifers

The size of the ovary varies substantially among cattle. This variation may influence the potential of the ovary to produce follicles. In the present study, we examined whether a relationship exists between the weight of the ovary and the number of antral follicles >or=1 mm. Paired ovaries were obtained from Holstein x Japanese Black F1 heifers. Follicles were classified into three size categories (small: 1.0-<5.0 mm, medium: 5.0-<8.5 mm and large: >or=8.5 mm), and the number of follicles in each category was recorded. Large variations in the weight of ovaries and the number of follicles were observed among animals. Significant positive correlations (r>or=0.4, P<0.001) were found between the weight of intact ovaries and the number of follicles in all three categories for the ovary contralateral to CL (OCC) and in the small follicles for the ovary ipsilateral to CL (OIC). Significant positive correlations (r>0.4, P<0.0001) were also observed between the weight of ovaries devoid of CL and follicles and the number of small and medium follicles in both OIC and OCC, indicating that the correlation is not due to the increase in ovarian weight associated with the increase in follicular number. Paired ovaries contained a similar number of small and medium follicles, and significant positive correlations were observed between them (r>0.6, P<0.0001). There were significant positive correlations between the weight of OCC and the number of small and medium follicles in paired ovaries (r>0.4, P<0.0001). These results suggest that 1) the weight of an ovary reflects the potential of the ovary to produce antral follicles, and 2) a rough estimation of follicular population might be possible by using the weight of the ovary contralateral to CL in heifers.     

Development of a male sterile eggplant by utilizing the cytoplasm of Solanum virginianum and a biparental transmission of chloroplast DNA in backcrossing

To develop a male sterile line of eggplant (Solanum melongena L.) utilizing the cytoplasm of S. virginianum, an interspecific F₁ hybrid between S. virginianum and S. melongena ‘Senryo Nigou’ was continuously backcrossed to S. melongena ‘Uttara’ using ‘Uttara’ as a recurrent pollen parent and four backcross generations, BC₁, BC₂, BC₃ and BC₄ were produced. All the plants in backcross generations were anther indehiscent although the F₁ hybrid, S. virginianum and S. melongena were dehiscent. Pollen stainability with acetic carmine and in vitro germination ability of pollen in all the backcross progenies were quite lower than those of the parental species. Fruit set percentage, number of seeds per fruit and seed germination rate were high in all the backcross progenies. The present results indicate that anther indehiscent type of functional male sterile line of eggplant could be developed by utilizing the cytoplasm of S. virginianum. PCR-RFLP analysis of chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) were performed to identify the organelle inheritance. The F₁ hybrid and all the backcross progenies displayed maternal inheritance of mtDNA. The cpDNA of the examined single BC₁ plant exhibited the recombinant cpDNA pattern of the parental F₁ hybrid and ‘Uttara’, indicating occurrence of the biparental inheritance of cpDNA. As all the BC₂, BC₃ and BC₄ progenies showed the same recombinant cpDNA patterns of the BC₁ plant, the recombinant cpDNA might be stable and harmonize with the nuclear genome of S. melongena. The present male sterile line can contribute to expand the male sterility source of eggplant.     

ISSR variations in eggplant (Solanum melongena L.) and related Solanum species

Inter-simple sequence repeat (ISSR) analysis was performed in eight cultivars of eggplant (Solanum melongena) and 12 accessions in eight related Solanum species to evaluate the applicability of this analysis for assessing the phylogenetic relationships and identifying cultivars. A total of 552 polymorphic amplified bands were obtained from 34 of the 100 primers tested, and the percentage of polymorphisms was 99.1%. Cluster analysis based on the ISSR markers classified the Solanum species into seven groups: (i) S. melongena; (ii) S. aethiopicum and S. anguivi; (iii) S. incanum; (iv) S. violaceum and S. kurzii; (v) S. macrocarpon; (vi) S. virginianum and (vii) S. torvum. Combining the ISSR markers obtained by a few of the 34 primers was enough for distinguishing of the eight cultivars of eggplant. This ISSR analysis was demonstrated to be available for the phylogenetic study and the cultivar identification.     

Treatment of Metastatic Equine Melanoma with a Plasmid DNA Vaccine Encoding Streptococcus Pyogenes EMM55 Protein

A 19-year-old castrated male Arab/Quarter horse presented with an extensive history of cutaneous metastatic melanoma. Over a period of 8 months, a total of 8 doses of plasmid DNA vaccine expressing the Streptococcus pyogenes emm55 gene (pAc/emm55) were administered intratumorally at 300 μg/dose via a needless injector. Upon completion of the vaccination protocol, the size of the injected lesions, on average, were reduced by 40.3% from the initial size measurements. Lesions that were not injected were reduced by 47.6%. The overall reduction in total tumor burden was 42.3%. Tumor regression was also associated with the augmentation of antimelanoma IgG antibody response, thus implying that an induction of an effective antimelanoma response would be of great advantage in the management of equine melanoma.     

Effects of ammonia and hydrogen sulfide on physical and biochemical properties of the claw horn of Holstein cows

The effects of ammonia and hydrogen sulfide on the physical and biochemical properties of the claw horn of Holstein cows were evaluated. Significant (P < 0.05, 0.01) decreases in hardness and elasticity were found in claw horns soaked in ammonia (NH₃) and hydrogen sulfide (H₂S) solutions compared with those that were soaked in water for 12, 24, and 48 h. Water absorption rate, as a indicator of permeability barrier function, increased significantly (P < 0.05) over time during the soaking period and was found to be dependent on the concentrations of NH₃ and H₂S in the solutions. The contents of ceramide, the main lipid component for the permeability barrier system of the stratum corneum, were significantly decreased in claw horns soaked in NH₃ and H₂S solutions compared with the values before soaking. Quantities of eluted protein released from claw horns treated with NH₃ and H₂S solutions were approximately 20 times and 30 to 40 times greater than those released from claw horns treated with water alone. Interestingly, the quantities of cytokeratin 10, the main cytoskeletal protein of the stratum corneum, eluted from claw horns treated with NH₃ and H₂S solutions were markedly greater than the quantity released from horns soaked in water. Our results suggest that abnormal changes in the physical property of claw horn caused by NH₃ and H₂S treatment are due to disruption of the biochemical property of the claw horn induced by these chemical agents derived from slurry.     

Genetic variations of isozymes in cultivated sesame (Sesamum indicum L.)

Patterns of variation for seven enzyme systems were studied in 68 accessions of cultivated sesame (Sesamum indicum L.), 12 from Japan, 15 from Korea and 41 from Thailand. Only one enzyme system, isocitrate dehydrogenase (IDH), of these exhibited variation. The IDH isozymes were shown to be controlled by a single locus (Idh) with two alleles. The two alleles were widely distributed in the accessions from the three countries. As few gene markers which have simple genetic control are available in sesame, these IDH isozymes could contribute to a range of studies in the breeding and genetics of sesame. This revised version was published online in July 2006 with corrections to the Cover Date.     

Successful interspecific hybridization between Cucumis sativus L. and C. hystrix Chakr.

Interspecific F₁ hybrids were obtained from a cross between Cucumis sativus L. (2n = 2x = 14) and C. hystrix Chakr. (2n = 2x = 24). Controlled crossing resulted in fruit containing embryos which were excised and rescued on a Murashige and Skoog solid medium. A total of 59 vigorous plants were obtained from a fruit containing 159 embryos (37.3% regeneration rate). Hybrid plants were morphologically uniform. The multiple branching habit, densely brown hairs (especially on corolla and pistil), orange-yellow collora, and ovate fruit of F₁ hybrid plants were similar to that of the C. hystrix paternal parent. While appearance of the first pistillate flower was more similar to that of C. sativus maternal parent than to C. hystrix, staminate flower appearance was mid-parent in occurence. The diameter and internode length of stem, shape and size of leaves and flowers were intermediate when compared to the parents. An elongated green, trilobate style/stigma which was not apparent in either parent was observed in staminate flowers of F₁ plants. Similarly, the style/stigma of pistillate flower of F₁ plants were longger when compared to their parents. The brown pubescence observed on pistillate flowers of the F₁ and C. hystrix was not observed on the C. sativus parent. The somatic chromosome number of F₁ plants was 19. Two morphologically distinct groups of chromosomes were observed in the F₁ hybrid; 7 relatively large chromosomes characteristic of C. sativus, and 12 smaller chromosomes characteristic of C. hystrix. Analysis of malate dehydrogenase isozyme banding patterns provided additional comfirmation of hybridity. Reciprocal crossing of F₁ plants to either parent and self-crossing indicated that the hybrids were male and female sterile. This revised version was published online in July 2006 with corrections to the Cover Date.     

Detection of recombinant DNA segments introduced to genetically modified maize (Zea mays)

Polymerase Chain Reaction (PCR) techniques are increasingly used for the detection of genetically modified (GM) crops in foods. In this paper, recombinant DNAs introduced into the seven lines of GM maize, such as Event 176, Bt11, T25, MON810, GA21, DLL25, and MON802, are sequenced. On the basis of the obtained sequence, 14 primer pairs for the detection of the segments, such as promoter, terminator regions, and construct genes, were designed. To confirm the specificities of the designed primer pairs, PCR was performed on genomic DNAs extracted from GM and non-GM maize, GM and non-GM soy, and other cereal crops. Because the presence of the corresponding DNA segments was specifically detected in GM crops by the designed primer pairs, it was concluded that this method is useful for fast and easy screening of GM crops including unauthorized ones.