Histocytological specificities of adrenal cortex in the New World Monkeys, Aotus lemurinus and Saimiri boliviensis

The New World monkey Aotus spp. (night monkeys) are expected for use of valuable experimental animal with the close species of Saimiri spp. (squirrel monkeys). Saimiri is known to show spontaneous hypercortisolemia, although few reports in Aotus. We compared basic states of blood steroid hormones and histological structure of the adrenal glands in two monkeys. Serum cortisol and ACTH levels were statistically lower in Aotus than Saimiri. Conversely, Aotus adrenocortical area showed significant enlargement, especially at the zona fasciculata. Electron microscopic observation at Aotus fasciculata cells revealed notable accumulation of large lipid droplets and irregular shapes of the mitochondrial cristae. These results suggest potential differences in cellular activities for steroidogenesis between Aotus and Saimiri and experimental usefulness in adrenocortical physiology and pathological models.     

Impaired female fertility in tubulointerstitial antigen-like 1-deficient mice

Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1] or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted to extraembryonic regions during the postimplantation period and detected marked expression in mouse Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the postimplantation period, suggesting that it plays a physical and physiological role in embryo development and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to determine the role of Tinagl1 during embryonic development and pregnancy, we generated Tinagl1-deficient mice. Although Tinagl1^–/– embryos were not lethal during development to term, homologous matings of Tinagl1^–/– females and Tinagl1^–/– males showed impaired fertility during pregnancy, including failure to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did not differ between Tinagl1^–/– and Tinagl1^flox/flox. In vitro fertilization followed by embryo culture also demonstrated the normal developmental potential of Tinagl1-null embryos during the preimplantation period. Our results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and they suggest that although the potential of Tinagl1^–/– oocytes is normal, Tinagl1 is related to fertility in adult females but is not essential for either fertilization or preimplantation development in vitro.     

Determination of nucleotide sequence of SRY gene in sika deer (Cervus nippon)

The aim of the present study was to determine the whole nucleotide sequence of the open reading frame of the sex‐determining region Y (SRY‐ORF) in wild sika deer. The SRY gene of wild sika deer was obtained by polymerase chain reaction (PCR) with DNA from blood samples. The whole nucleotide sequence of the SRY‐ORF in wild sika deer consisted of 687 bp and encoded 229 deduced amino acids. In comparison with the bovine SRY gene, the percentage of nucleotide sequence homology was 91.0% in the overall ORF, and those of the N‐terminal, high mobility group (HMG) box, and C‐terminal regions within ORF were 88.9%, 96.2% and 87.9%, respectively. The nucleotide sequences of sika deer SRY‐ORF characterized in the present study can be used for phylogenetic analysis or sexing in wild sika deer.     

Effects of loosing Aigamo ducks on the growth of rice plants, weeds, and the number of arthropods in paddy fields

Aigamo duck farming has been noticed as one of the techniques of environmental conservation agriculture. This study was carried out to investigate the effects of loosing Aigamo ducks on the growth and production of rice plants, the quantity of weeds and arthropods, and the balance of nitrogen (N) in paddy fields by changing the density of the Aigamo ducks. A paddy field was divided into three test plots: a 10-Aigamo-duck plot, a five-Aigamo-duck plot, and a weeding plot. The results show that the height, number of culms, and yield crops of the rice plants increased more in the 10-Aigamo-duck plot and the five-Aigamo-duck plot than that of the weeding plot. Millet ( Echinochloa oryzicola ) remained in both the Aigamo duck plots. The weeding plot was covered with monochoria ( Monochoria vaginalis ). In both the Aigamo duck plots, the outbreak of total arthropods was lower than that of the weeding plot, but the number of rice plants damaged by grass leaf rollers ( Cnaphalocrocis medinalis ) was increased. The number of spiders, regarded as useful insects, did not differ that much between the experimental plots. The N content of the soil did not differ as an effect of loosing the Aigamo ducks. The rice plants in the 10-Aigamo-duck plot absorbed more N than the rice plants in the other plots.     

Molecular sexing of Jungle crow (Corvus macrorhynchos japonensis) and Carrion crow (Corvus corone corone) using a feather

A molecular sexing method using the intron‐size difference between chromo‐helicase‐DNA binding protein (CHD1) genes on the Z and W sex chromosomes (CHD1Z and CHD1W, respectively) was developed for wild Jungle crows and wild Carrion crows. The polymerase chain reaction product sizes were 661 bp for CHD1Z and 465 bp for CHD1W in both the Jungle and the Carrion crows. Each male crow sample produced a single fragment (CHD1Z), whereas female samples produced two fragments (CHD1Z and CHD1W), which differed by 200 bp in crows. In the present study, sexing live Jungle and Carrion crows was performed by applying the method to a feather for molecular sexing.     

Linkage mapping of four chicken calpain genes

Calpains are intracellular Ca²⁺‐dependent proteases and enzymes that contribute to growth and meat quality. In the present study, we identified polymorphisms in four calpain genes (CAPN1, CAPN2, CAPN3, and CAPN1.5) expressed ubiquitously in chicken using polymerase chain reaction‐restriction fragment length polymorphism, and mapped them using two backcross families (East Lansing (EL) and Kobe University (KU)). CAPN2 and CAPN1.5 mapped to two locations on chromosome 3 about 30 cM apart, while CAPN3 mapped to chromosome 5. CAPN1 was linked to a previously unlinked microsatellite marker LEI0140 to form a new linkage group called E66. CAPN2 and CAPN3 extend the amount of conserved synteny between chicken chromosome 3 and human chromosome 1, and between chicken chromosome 5 and human chromosome 15, respectively. Although CAPN2, CAPN3, and CAPN1.5 were found in the University of California Santa Cruz chicken genome browser gateway, CAPN1 and LEI0140 were not in specific genomic positions.     

Pinpointing the candidate region for muscular dystrophy in chickens with an abnormal muscle gene

Muscular dystrophies, a group of inherited diseases with the progressive weakness and degeneration of skeletal muscle, contain genetically variable diseases. Though chicken muscular dystrophy with abnormal muscle (AM) has long been known, the gene responsible has not yet been identified. In this study, a resource family for AM was established with 487 F2 individuals and 22 gene markers, including microsatellite and insertion–deletion markers, were developed. The haplotypes were analyzed with these markers for the candidate region of GGA2q described in a previous study. The candidate region was successfully narrowed down to approximately 1Mbp. The region included seven functional genes predicted as the most likely AM candidates.     

Successful blastocyst production by intracytoplasmic injection of sperm after in vitro maturation of follicular oocytes obtained from immature female squirrel monkeys (Saimiri boliviensis)

Advanced reproductive technologies are being applied for the propagation of squirrel monkeys, to ensure their preservation as a genetic resource and the effective use of their gametes in the future. In the present study, oocytes and spermatozoa were collected from live squirrel monkeys, following which piezo intracytoplasmic sperm injection (ICSI) was performed using these gametes. Follicular development was induced by administering equine chorionic gonadotropin (eCG) containing inhibin antiserum to an immature squirrel monkey female. The unilateral ovary was excised after the administration of human chorionic gonadotropin (hCG), to induce ovulation, following which the larger developed follicular oocytes were collected. Follicular oocytes were prepared for ICSI using sperm from the epididymal tail of a unilateral testis extracted from a mature male. The embryos were continuously incubated in CMRL 1066 medium supplemented with 10% (v/v) fetal bovine serum. Embryo culture was performed with cumulus cells. Two experiments of ICSI carried out with three females resulted in 14 mature oocytes from the 49 cumulus-oocyte complexes collected and five embryos, three of which developed into blastocysts. These blastocysts were vitrified, thawed, and transferred to recipient monkeys, but no pregnancies resulted. In conclusion, the present study is the first to successfully produce ICSI-derived blastocysts from MII oocytes obtained by means of hormone administration (a combination of eCG+inhibin antiserum and hCG) and in vitro maturation in immature squirrel monkeys.     

A Mathematical Model for Juice Extraction from Chopped Sweet Sorghum

Juice extraction from chopped sweet sorghum is an example of flow through porous media. Darcy's law is often used to express this type of phenomenon. However, using Darcy's law to construct a mathematical model to predict juice extraction from chopped sweet sorghum is difficult, because the volume of the porous media changes during the pressing operations. A mathematical model was developed from fundamental analysis to predict the juice extraction ratio of chopped sweet sorghum, and experiments were conducted to verify the model. An experimental piston-cylinder assembly was developed to conduct the validation experiments. The parameters in the developed model were estimated by using non-linear regression analysis from the experimental data. Plots of the mathematical model agreed well with experimental data. R2 (coefficient of determination) values for all the regressions studied were higher than 0.99. Results showed that the juice extraction ratio of chopped sweet sorghum approached an asymptote with a maximum value that depended on the physical form of the sample. The model could help in understanding the mechanics of juice extraction from chopped sweet sorghum.     

Detection of nucleolar organizer regions on chromosomes by flourescence in situ hybridization with human 28S rRNA gene and cloning of 28S rRNA gene in Sika deer

The number and loci of nucleolar organizer regions (NOR) on chromosomes in Sika deer (Cervus nippon centralis) were determined by fluorescence in situ hybridization with a human 28S ribosomal RNA (rRNA) gene as a probe. Sika deer that live in Nikko National Park and its neighboring areas (Asio and Seta) in Japan were used. All of the analyzed metaphases had three or four NOR at the end of the first and second longest telocentric autosomes. Nucleolar organizer region association, which is associated specifically on parts of NOR between chromosomes, was also observed clearly. A Sika deer 28S rRNA gene was produced by a polymerase chain reaction method. The nucleotide sequence of a Sika deer 28S rRNA gene determined by an automatic sequencer was 97 bp, and showed homogeneity of 88% for the human sequence.