Comparative IFN-τ Secretion after Hatching by Bovine Blastocysts Derived Ex Vivo and Completely Produced In Vitro

The interferon-tau (IFN-tau) secretion levels after hatching by bovine blastocysts derived from in vitro maturated oocytes (Group A) and from in vivo (Group B) were investigated considering embryo quality. Only very homogeneous blastocysts of excellent or good quality were considered from day 7 of culture (Group A) and day 7 after artificial insemination with frozen-thawed from the same bull used for in vitro fertilization (Group B). All embryos were individually cultured into a 50 microl droplet of synthetic oviduct fluid medium with 10% fetal calf serum. After 24-h culture both Group A (n=44) and B (n=40) secreted <54 pm IFN-tau. After 48-, 72-, 96- and 120-h culture, Group A daily secreted 143 +/- 24 pm IFN-tau (n=19) vs 85 +/- 12 pm IFN-tau (n=21) for Group B (p < 0.01), 491 +/- 128 pm IFN-tau (n=29) vs 216 +/- 37 pm IFN-tau (n=23) (NS), 499 +/- 135 pm IFN-tau (n=26) vs 353 +/- 93 pm IFN-tau (n=21) (NS), 559 +/- 136 pm IFN-tau (n=22) vs 333 +/- 75 pm IFN-tau (n=20) (NS), respectively. Taken all together during 5 days, Group A produced per embryo 1690 +/- 290 pm IFN-tau (n=22) vs 982 +/- 182 pm IFN-tau (n=20) for Group B (p < 0.05). For all culture time there were sizable percentages of embryos that did not produce concentrations of IFN-tau above a certain cut-off level, and as such were not used to compute the means. In respect of the embryo quality whatever the groups after days 7-12 of culture, IFN-tau secretions were 1815 +/- 453 pm (n=10) for the embryos of excellent quality vs 1356 +/- 200 pm (n=28) for those of good quality (NS) and 360 +/- 188 pm (n=4) (p < 0.05) for embryos of fair quality. A positive relationship between IFN-tau production and in vitro development of quality I embryos was observed, whatever the embryos origins and, the embryos completely produced in vitro secreted more IFN-tau than the embryos produced in vivo.     

Distribution of prion protein genotypes in breeds of sheep in New Zealand

AIM: To use an established high through-put genotyping procedure to gain an estimate of the frequency of alleles of the prion protein (PrP) gene in some common sheep breeds in New Zealand.

METHODS: Using a genotyping procedure based on matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF), DNA samples from 3,024 sheep from New Zealand, including breeds such as Romney, Texel, Coopworth, Merino and mixedbreed, were isolated, genotyped and the results analysed.

RESULTS: The 15 scrapie genotypes commonly reported, and derived from the five commonly reported allelic variants (ARR, ARQ, AHQ, ARH and VRQ), were all observed in the samples analysed. The estimates were indicative of the frequencies in the population of alleles present in breeds of sheep in New Zealand. There was a significant difference between the frequencies of alleles between breeds, but the ARQ, followed by the ARR allele, were, except in Carwell sheep, the most common alleles present.

CONCLUSION: This study gave an indication of the percentages of PrP gene alleles in sheep in New Zealand, including data previously unreported from breeds in this country. It is of interest because of the relatively large size of the sheep population in New Zealand compared with many countries, and it provides some useful information on the genetic susceptibility or resistance of the sheep population in New Zealand to scrapie. The frequencies of the alleles can be different for an individual breed compared between countries.     

Progesterone and Caspase-3 Activation in Equine Cyclic Corpora Lutea

Soon after ovulation, the newly formed corpus luteum (CL) starts secreting progesterone (P(4)), necessary for implantation. The CL, an ovarian transient endocrine organ, undergoes growth and regression throughout its life span. The objective of this study was to evaluate if caspase-3 mediates cell death in the equine cyclic luteal structures and relate it to luteal endocrine function. Blood and luteal tissue were collected during the breeding season after slaughter from 38 randomly assigned cycling mares. Luteal tissues were classified as corpora haemorrhagica (CH; n = 7); mid luteal phase corpora lutea (Mid-CL; n = 17); late or regressing corpora lutea (Late-CL; n = 9) and corpora albicans (CA; n = 5). Plasma P(4) concentration, determined by radioimmunoassay, showed a significant increase from CH to Mid-CL (p < 0.001), followed by a decrease to Late-CL (p < 0.001) and CA (p < 0.001). Caspase-3 processing and poly (ADP) ribose polymerase (PARP) degradation were assessed by western blotting. Active caspase-3 was twofold increased in Mid-CL, Late-CL and CA as compared with CH (p < 0.05). Immunocytochemistry also showed a significant increase in caspase-3 expression in large luteal cells in all structures when compared with CH (p < 0.05). Consistently, the endogenous caspase-3 substrate, PARP, was markedly degraded from CH to CA (p < 0.05). In fact, the ratio of full-length to degraded PARP showed a significant decrease from CH to Mid-CL, Late-CL and CA (p < 0.05). Finally, the decrease in P(4) from Mid- to Late-CL coincided with no further increases in apoptosis. In conclusion, these results suggest that the effector caspase-3 of apoptosis, might play an important role during luteal tissue involution in the mare, even though its relationship with P(4) remains to be elucidated.     

Study of Sperm Concentration,Seminal Plasma Composition and their Physiological Correlation in the Persian Sturgeon,Acipenser persicus

The objectives of the present study were to determine ionic and organic composition of seminal plasma, sperm concentration and their relationships in the Persian sturgeon (Acipenser persicus). In this regard, ionic content (Na⁺, K⁺, Cl^?, Ca²⁺ and Mg²⁺) and organic content (total protein, glucose, cholesterol and triglyceride) along with sperm concentration were measured in 17 specimens of the Persian sturgeon. The seminal plasma contained 59.53 ± 2.56 mm /l sodium, 9.1 ± 1.42 mm chloride, 4.72 ± 0.3 mm potassium, 1.45 ± 0.075 mm calcium and 0.7 ± 0.072 mm magnesium. The following organic contents were found: total protein 0.11 ± 0.02 g/dl, glucose 22.18 ± 4.16 mg/dl, cholesterol 6.67 ± 1.04 mg/dl and triglyceride 15.2 ± 0.65 mg/dl. The mean sperm concentration was estimated to be 1.6 ± 0.12 (×10⁹ sperm/ml). A significant relationship was found between sperm concentration and K⁺ of seminal plasma (r = 0.533, p < 0.05). Significant correlations were observed between ionic contents: Na⁺ vs Cl^? (r = ?0.854, p < 0.01) and Mg²⁺ vs K⁺ (?0.583, p < 0.05). Also, level of triglyceride was negatively correlated with Mg²⁺ (r = ?0.503, p < 0.05). Presented data could be considered as a complementary study for developing special extenders and protectant solutions for improving artificial fertilization in this valuable species.     

Prevalence of Bartonella species,Rickettsia felis,haemoplasmas and the Ehrlichia group in the blood of cats and fleas in eastern Australia

Objectives To define the prevalence of Bartonella spp., Rickettsia felis, Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ (Mhm) and ‘Candidatus Mycoplasma turicensis’ (Mtc) in cats and their fleas in eastern Australia. Design and procedure Conventional PCR assays that detect Bartonella spp., M. haemofelis, Mhm, Mtc, Rickettsia spp., Ehrlichia spp., Anaplasma spp. and Neorickettsia spp. were performed on DNA extracted from blood and fleas collected from 111 cats. Cat sera were assayed by ELISA for IgG of Bartonella spp. Results DNA of M. haemofelis, Mtc and Mhm was amplified from 1 (0.9%), 1 (0.9%) and 17 cats (15.3%), respectively. Only DNA of Mhm was amplified from the 62 of 111 pooled flea samples (flea sets; 55.9%). Overall, the prevalence rates for Bartonella spp. DNA in the cats and the flea sets was 16.2% (18 cats) and 28.8% (32 flea sets), respectively. Bartonella spp. IgG was detected in 42 cats (37.8%), of which 11 (26.2%) were positive for Bartonella spp. DNA in their blood. R. felis DNA was amplified from 22 flea sets (19.8%), but not from cats. Overall, DNA of one or more of the organisms was amplified from 27% (30) of cats and 67.6% (75) of the flea sets. Conclusions This is the first Australian study to determine the prevalence of R. felis and B. clarridgeiae in both fleas and the cats from which they were collected. Flea-associated infectious agents are common in cats and fleas in eastern Australia and support the recommendation that stringent flea control be maintained on cats.     

Allelopathic potential of native plants against water hyacinth

Classical biocontrol of water hyacinth using insects in India is constrained by seasonal occurrence of water flow and interrupted host range. Use of fungal pathogens is also difficult due to lack of shelf-life and virulence under severe climatic fluctuations and a lack of knowledge of spray techniques. Hence, the allelopathic potential of native plants is reviewed for use as an alternative bio-control tactic. Dried powder of the leaves of Omavalli Coleus amboinicus L. at 40 g l⁻¹ as a water suspension killed water hyacinth within 24 h reducing the fresh weight by 80.72% and the dry weight by 75.63% within one week. The lowest dose required to kill the whole plant was 10 g l⁻¹. Coleus powder was injurious to cut leaves of water hyacinth even at 0.1 g l⁻¹ dose as it was absorbed directly by the cut leaf, indicating that the dose required to kill the whole plant could still be reduced, if either the natural product or the active principle is formulated for absorption through foliage.