Y‐chromosomal variation confirms independent domestications of swamp and river buffalo

Y‐chromosomal variation in the water buffalo was analysed by sequencing of DBY, ZFY and SRY gene segments. A clear separation of the paternal lineages of the river and swamp types parallels the differences between their maternal lineages and nuclear DNA. Sequence divergence was found to be comparable to the divergence of taurine cattle and zebu, and this divergence predated domestication, confirming that river and swamp buffalo originated from different wild populations. Within a sample of 23 Thai swamp buffaloes, we identified four haplotypes with different geographical distributions, two of which were shared by Thai wild buffaloes.     

Fine structure of wing scales of butterflies, Euploea mulciber and Troides aeacus

Wing scales of male Euploea mulciber (E. mulciber) and Troides aeacus (T. aeacus) butterflies were investigated from interest in photonic crystal by scanning electron microscopy and optical reflectance measurement. On the basis of the structural observation, the colouration in different areas in their wings was discussed. It was particularly deduced that a violet-green iridescence characteristic of E. mulciber’s forewing is caused only in a wavelength range from ∼380 to ∼510 nm by multiple interference from a highly tilted, triple-layered cuticle arrangement on the brown scales. It was also found that T. aeacus does not produce a blue-green sheen such as observed by Troides magellanus because its scales have no multiple cuticle layers but microrib layers unable to produce any backscattering diffraction.     

Reproductive performance of dairy cows with ovarian cysts after synchronizing ovulation using GnRH or hCG during the warm or cool period of the year

This study was designed to compare the reproductive response to timed AI of lactating dairy cows with cystic ovarian follicles treated with GnRH or hCG to synchronize ovulation. The effectiveness of treatment during the warm or cool period of the year was also compared. Cows were given 12 microg GnRH-agonist i.m. on day 0 of the protocol, 15 mg PGF(2alpha) i.m. on day 7, and either GnRH-agonist (GPG treatment) or 3000 IU hCG i.m. (GPH treatment) on day 9, followed by timed AI. The cows were randomly chronologically assigned to GPG (n=130) or GPH (n=136) group. All cows were inseminated at fixed time 16-22 h after the end of treatment. During the warm period the pregnancy rate to first AI was 12% (7/60) and 21% (14/68) for the GPG and GPH groups, respectively, there being no significant differences between groups; the cumulative pregnancy rate was 22% (13/60) and 21% (14/68) for the GPG and GPH groups, respectively, again with no significant intergroup differences. During the cool period pregnancy rate to first AI was not different between groups: 29% (20/70) for GPG and 32% (22/68) for GPH, respectively; whereas the cumulative pregnancy rate was significantly higher (P<0.05) for the GPH groups than for the GPG group: 56% (39/70) and 78% (53/68), respectively. These findings indicate that during the warm period, the pregnancy rates of the cystic cows were similar whether they received GPG or GPH treatment, during the cool period, there is a beneficial effect to use hCG at day 9 of the ovsynch protocol compared GnRH on cumulative pregnancy rate.     

Enzymatic production of N-acetyl- -glucosamine from chitin. Degradation study of N-acetylchitooligosaccharide and the effect of mixing of crude enzymes

N-Acetyl- -glucosamine (GlcNAc) was produced from chitin by use of crude enzyme preparations. The efficient production of GlcNAc by cellulases derived from Trichoderma viride (T) and Acremonium cellulolyticus (A) was observed by HPLC analysis compared to lipase, hemicellulase, and pectinase. β-Chitin showed higher degradability than α-chitin when using cellulase T. The optimum pH of cellulase T was 4.0 on the hydrolysis of β-chitin. The yield of GlcNAc was enhanced by mixing of cellulase T and A.     

Plant regeneration of mangosteen via nodular callus formation

Nodular callus was induced at a high frequency on young purple red, 5–15 mm long laminae taken from in vitro grown plants of mangosteen. The optimal medium was composed of Murashige and Skoog (MS) nutrients supplemented with 2.22 μM benzyladenine (BA), 2.25 μM thidiazuron (TDZ), 500 mg l^-1 polyvinylpyrrolidone (PVP 360 000) and 3% sucrose. A multiplication rate of two–three was obtained by subculture of the nodular callus at 3–4-week intervals. Plantlet regeneration from the nodules was achieved by transfer to woody plant medium (WPM) with 500 mg l^-1 PVP, 0.4 μM BA and 3% sucrose and overlaying with half strength liquid MS containing 0.32 μM naphthaleneacetic acid (NAA), 0.13 μM BA and 3% sucrose. Elongated shoots were rooted to 100% when wounded at the base of shoot, dipped in 4.4 mM indolebutyric acid (IBA) solution in the dark for 15 min and cultured on WPM supplemented with 1.11 μM BA, 0.25% activated charcoal, 34.5 μM phloroglucinol (PG) and 3% sucrose. This revised version was published online in June 2006 with corrections to the Cover Date.     

The association between growth rate, body weight, backfat thickness and age at first observed oestrus in crossbred Landrace x Yorkshire gilts

The present study aims to investigate the association between growth rate (GR), body weight (BW), backfat thickness (BF) and age at first observed oestrus in crossbred Landrace x Yorkshire (LY) replacement gilts in the tropics. The study was carried out on five commercial swine herds in Thailand between 2004 and 2006. A total of 6946 LY gilts were included. The gilts entered the herd at about 163 days of age. The BW (kg) and BF (mm) of the gilts were measured when the gilts entered the gilt pools and again when the gilts were sent to the breeding house. The GR from birth to entry into the gilt pools (birth to 90 kg BW) (GRe), the GR from entry into to exit from the gilt pools (91-134 kg BW) (GRi) and the GR from birth until the gilts were sent to the breeding house (birth to 134 kg BW) (GRs) were calculated. The relationship between age at first observed oestrus and GRe, GRs, GRi, BW and BF were analyzed. Pearson's correlation and four general linear models (GLMs) were conducted. On average, the gilts showed first observed oestrus at 200+/-28 days of age. The means of age at first observed oestrus varied from 188 to 251 days (P<0.001) among the herds. The GRs of the gilts significantly correlated with the BW (r=0.55, P<0.001) of the gilts when they were sent to the breeding house and the age at first observed oestrus (r=-0.40, P<0.001). Gilts with a high GRe and GRs were younger at first observed oestrus compared to gilts with a low GRe and GRs. On average, the gilts with GRs of over 604 g/day showed first observed oestrus before 5 months of age. GRi was not correlated with the age at first observed oestrus (P>0.05). Neither the BF of the gilts at entry nor the BF that the gilts gained within the gilt pools significantly correlated with age at first observed oestrus (P=0.29 and P=0.69, respectively). But the gilts with a higher BF at entry tended to have a higher BW when they were sent to the breeding house (r=0.44, P<0.001). The present study indicates that replacement gilts with a high GR (both GRe and GRs) tend to show sign of oestrus earlier than gilts with a low GR (both GRe and GRs).     

Lipid profiles of sperm and seminal plasma from boars having normal or low sperm motility

Sperm plasma membrane lipids have an important role to play in determining membrane fluidity and sperm motility. The objective of the present study was to determine whether there are differences in the lipid and fatty acid (FA) composition of boar sperm and seminal plasma in the ejaculates of boars having different sperm motilities. Semen was collected from two groups of boars having normal (> 60%; n = 53) or low (< 60%; n = 53) motility sperm and the semen was evaluated for motility, morphology and vitality. The semen was then centrifuged to separate the sperm from the seminal plasma and both were kept at −20 °C until analyzed for lipid content and FA profile by gas chromatography. Total antioxidant status (TAS) of seminal plasma was determined using a commercial kit. There were differences (P ≤ 0.05) in sperm total lipids, cholesterol, saturated fatty acids (SFA), phospholipids, n-3 polyunsaturated fatty acids (PUFA), docosahexaenoic acid (DHA) and the ratio of n-6:n-3 PUFA between boars with normal and low motility sperm. Total lipids, cholesterol, phospholipids, PUFA, DHA and n-3 PUFA were positively correlated with sperm motility, viability, normal morphology and normal plasma membrane. In contrast, SFA and the ratio of n-6: n-3 PUFA were negatively correlated (P ≤ 0.05) with sperm motility, viability, normal morphology and normal plasma membranes. The TAS of seminal plasma from boars having normal motility sperm was higher (P ≤ 0.05) than that of boars having low motility sperm and TAS was positively correlated (P = 0.0001) with sperm motility, viability, normal morphology and normal plasma membranes. In summary, differences in sperm motility were related to n-3 PUFA content in the sperm plasma membrane and extracellular antioxidants in seminal plasma which protect sperm plasma membranes from lipid peroxidation during periods of oxidative stress.     

Resistance to three thrips species in Capsicum spp. depends on site conditions and geographic regions

Capsicum species are commercially grown for pepper production. This crop suffers severely from thrips damage and the identification of natural sources of thrips resistance is essential for the development of resistant cultivars. It is unclear whether resistance to Frankliniella occidentalis as assessed in a specific environment holds under different conditions. Additionally, other thrips species may respond differently to the plant genotypes. Screening for robust and general resistance to thrips encompasses testing different Capsicum accessions under various conditions and with different thrips species. We screened 11 Capsicum accessions (C. annuum and C. chinense) for resistance to F. occidentalis at three different locations in the Netherlands. Next, the same 11 accessions were screened for resistance to Thrips palmi and Scirtothrips dorsalis at two locations in Asia. This resulted in a unique analysis of thrips resistance in Capsicum at five different locations around the world. Finally, all accessions were also screened for resistance to F. occidentalis in the Netherlands using a leaf disc choice assay, allowing direct comparison of whole plant and leaf disc assays. Resistance to F. occidentalis was only partially consistent among the three sites in the Netherlands. The most susceptible accessions were consistently susceptible, but which accession was the most resistant differed among sites. In Asia, one C. chinense accession was particularly resistant to S. dorsalis and T. palmi, but this was not the most resistant accession to F. occidentalis. Overall, resistance to F. occidentalis correlated with S. dorsalis but not with T. palmi resistance in the C. annuum accessions. Damage inflicted on leaf discs reflected damage on the whole plant level. Our study showed that identifying broad spectrum resistance to thrips in Capsicum may prove to be challenging. Breeding programmes should focus on developing cultivars suitable for growing in defined geographic regions with specific thrips species and abiotic conditions.