Impact d’une méthode originale de synchronisation respiratoire sur la détection des lésions hépatiques en TEP/TDM au F-FDG

In ¹⁸F-Fluoro-Desoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT), respiratory motion induces bias in image interpretations. These movements can introduce organs misregistration between both modalities yielding erroneous attenuation correction and thus wrong maximum standardized uptake values (SUV_max). We present here the results of a clinical study which aims to assess the benefits of a novel respiratory gating method (CT-based) for liver lesions detection. Forty-nine patients planed to undergo hepatic surgery were addressed to our department for PET/CT examination before surgery. Each patient had both standard and CT-based protocols. Hepatic lesions described by two observers on PET images were compared with pathological analysis and intra-operative ultrasound. Sensitivities calculated for observer 1 were 60 and 64% for standard and CT-based, respectively. For the second observer, sensitivities were 58.7 and 72%. CT-based showed a significant increase (P < 0.01) of sensitivity on a per-lesion basis for one observer. CT-based did not improve inter-observer variability. At last, SUV_max were significantly higher with CT-based method (P < 0.001). Respiratory gating CT-based method is easily bearable by the patients. This procedure ensures good matching between both modalities and reduces motion-blurring effect in PET data. CT-based method improves liver lesions detectability and allows more accurate quantitation compared to non-gated FDG-PET/CT examinations.     

The effect of FISH and CARD-FISH on the isotopic composition of C- and N-labeled Pseudomonas putida cells measured by nanoSIMS

The use of nanoSIMS for the exploration of microbial activities in natural habitats often implies that stable isotope tracer experiments are combined with in situ hybridization techniques (i.e. fluorescence in situ hybridization (FISH) or catalyzed reporter deposition (CARD)-FISH). In this study, Pseudomonas putida grown on ¹³C- and ¹⁵N-labeled carbon and nitrogen, collected in exponential growth and stationary phases, was hybridized and analyzed by nanoSIMS. It was shown that ¹³C and ¹⁵N fractions decreased after FISH and CARD-FISH in comparison to chemically untreated cells. However, the fractions were influenced differently by various treatments. After paraformaldehyde fixation of exponentially growing cells, a reduction of the ¹³C and ¹⁵N fractions was measured from 94 ± 1.2% and 89.5 ± 3.8% to 90.2 ± 0.8% and 64 ± 4.6%, respectively, indicating that nitrogen isotopic composition was most influenced. A further decrease of the ¹³C and ¹⁵N fractions to 80.7 ± 6.5 and 59.5 ± 4.1%, respectively, was measured after FISH, while CARD-FISH decreased the fractions to 57.4 ± 3.0% and 47.1 ± 4.1%, respectively. The analysis of cells collected in different growth phases revealed that the effect of various treatments seemed to be dependent on the cell's physiological state. In addition, a mathematical model that can be used in further studies was developed in order to calculate the amount of carbon introduced into the cells by chemical treatments. These results can be valuable for environmental FISH-nanoSIMS studies where the isotopic composition of single cells will be used to quantitatively assess the importance of specific populations to certain biochemical processes and determine budget estimations.     

The effect of insemination time and sperm dose on pregnancy rate using sex-sorted ram sperm

The objective was to determine the optimum timing of insemination and minimum effective dose rate of sex-sorted ram sperm. Semen from three Merino rams was sorted into high purity X- and Y-chromosome bearing sperm populations. Ovulation was controlled in 732 Merino ewes using PMSG at progestagen pessary removal and GnRH 36 h later. Sorted (S) and non-sorted (NS) doses of 1 or 15 × 10⁶ motile, frozen-thawed sperm were inseminated laparoscopically at 50, 54, 58, 62, and 66 h after progestagen withdrawal. An additional treatment dose of 0.5 × 10⁶ S or NS sperm was inseminated at the 58 h time point (n = 60). Pregnancy was diagnosed by ultrasound at 60-62 d gestation. Both 1 × 10⁶ and 15 × 10⁶ sperm achieved similar pregnancy rates, regardless of sperm type, at 58 h (S1: 46 ± 9.4%; S15: 43 ± 9.3%; NS1: 41 ± 9.2%; NS15: 49 ± 9.4%). However, pregnancy rates were lower (P < 0.05) for doses of 1 than 15 × 10⁶ sperm inseminated at 50 (15 ± 6.3% vs. 36 ± 9.1%), 54 (14 ± 4.4% vs. 55 ± 7.3%), 62 (33 ± 6.9% vs. 54 ± 7.3%), and 66 h (29 ± 8.6% vs. 56 ± 9.5%). There was no difference between S and NS sperm for inseminations with 0.5 × 10⁶ motile sperm at 58 h after PR (15 ± 3.6% vs. 14 ± 3.3%), nor with 15 × 10⁶ motile sperm at all insemination times (49 ± 6.3% vs. 49 ± 6.3%). However, fertility was higher for S than NS sperm at the 1 × 10⁶ dose level (37 ± 6.1% and 16 ± 4.0%). More than 90% of lambs born were of the predicted sex. We hypothesise that the sorting process selects a homogeneous, fertile sub-population of sperm, removing those that are dead, damaged and morphologically abnormal.     

Gamma irradiation with different dose rates induces different DNA damage responses in Petunia x hybrida cells

In plants, there is evidence that different dose rate exposures to gamma (γ) rays can cause different biological effects. The dynamics of DNA damage accumulation and molecular mechanisms that regulate recovery from radiation injury as a function of dose rate are poorly explored. To highlight dose-rate dependent differences in DNA damage, single cell gel electrophoresis was carried out on regenerating Petunia x hybrida leaf discs exposed to LDR (total dose 50 Gy, delivered at 0.33 Gy min⁻¹) and HDR (total doses 50 and 100 Gy, delivered at 5.15 Gy min⁻¹) γ-ray in the 0–24 h time period after treatments. Significant fluctuations of double strand breaks and different repair capacities were observed between treatments in the 0–4 h time period following irradiation. Dose-rate-dependent changes in the expression of the PhMT2 and PhAPX genes encoding a type 2 metallothionein and the cytosolic isoform of ascorbate peroxidase, respectively, were detected by Quantitative RealTime-Polymerase Chain Reaction. The PhMT2 and PhAPX genes were significantly up-regulated (3.0- and 0.7-fold) in response to HDR. The results are discussed in light of the potential practical applications of LDR-based treatments in mutation breeding.     

Application of F magnetic resonance to study the efficacy of fluorine labeled drugs in the three-dimensional cultured breast cancer cells

The cellular monitoring of tumor response to treatments is important for drug discovery and drug development in cancer therapy. We studied efficacy of Herceptin, a common breast cancer drug conjugated with a fluorine organic compound, perfluoro-15-crown-5-ether (PFCE) which easily forms biocompatible emulsions. Three new pharmaceutical forms of Herceptin, Herceptin/PFCE, Herceptin/PFCE/Lipoplex and Herceptin/PFCE/HydraLink were synthesized for the ex vivo study of their efficacy in breast cancer treatment. The emulsions were administered to 10⁹ cells mL⁻¹ of HER-2 positive human adenocarcinoma (MCF-7) cells and the same amount of human mammary epithelial cells (HMEC) cultured in three-dimensional (3D) geometry using hollow fiber bioreactor (HFB) device. Following drugs administration ex vivo, fluorine-19 magnetic resonance imaging (¹⁹F MRI) was applied for cells imaging to measure their viability and to study drug efficacy over 72 h. To ensure optimum drug tracking, HydraLink was used to provide stable binding affinity of emulsified Herceptin to receptor while cationic lipid (Lipofectamine) was used to enhance lipophilicity of the emulsions.After 72 h of treatment with Herceptin, Herceptin/PFCE, Herceptin/PFCE/Lipoplex and Herceptin/PFCE/HydraLink the viability of cells was 54 ± 2%, 49 ± 3%, 43 ± 5% and 42 ± 1%, respectively, as compared with control 93 ± 2%. The efficacy (EC₅₀) of Herceptin conjugated with emulsions was found to be 970 ± 13 μg mL⁻¹ for Herceptin/PFCE, 645 ± 11 μg mL⁻¹ for Herceptin/PFCE/Lipoplex, 678 ± 7 μg mL⁻¹ for Herceptin/PFCE/HydraLink and 1000 ± 3 μg mL⁻¹ for Herceptin. The results show that fluorine emulsions improved the efficacy of Herceptin and ¹⁹F signal intensity changes validated drug efficiency. The significant correlations between duration of treatments and MCF-7 cells viability were observed. While we studied breast cancer cells, the fluorine emulsions could be applied for treatment of other cancer cells overexpressing HER-2.     

Embryo production in superovulated Angus cows inseminated four times with sexed-sorted or conventional, frozen-thawed semen

This study tested the hypothesis that four inseminations of commercially frozen sexed semen (≥2.1 × 10⁶ sperm per 0.25-mL straw) in superstimulated embryo donors would yield a percentage and quantity of transferable embryos similar to that achieved with conventional frozen semen. Bos taurus, angus cows (n = 32), stratified by age and body condition, were randomly allocated to receive four inseminations of frozen-thawed semen, either conventional semen (≥15 × 10⁶ sperm/straw; Conventional) or sexed semen (≥2.1 × 10⁶ sperm/straw; Sexed) from one of two AI sires. From 10 to 13 d after estrus, follicle-stimulating hormone (FSH) was given twice-daily, with prostaglandin F_2α given twice on the last day. Cows were inseminated once (1×) at first detected estrus and twice (2×) and once (1×) at 12 and 24 h later, respectively, with nonsurgical embryo recovery 7 d after first detected estrus. The study was repeated 30 d later (switch-back experimental design). The total number of ova per flush was similar between Conventional and Sexed treatments (10.9 ± 1.8 vs. 10.5 ± 1.6), but the number of Grade 1 embryos was greater (P < 0.01) for Conventional (4.3 ± 0.8 vs. 2.3 ± 0.7). Conversely, the mean number of unfertilized ova was greater (P < 0.05) for Sexed (5.6 ± 1.0 vs. 3.0 ± 1.2). There was no significant difference between treatments for numbers of degenerate, Grades 2 or 3, and transferable embryos and no significant differences between bulls in percentage of transferable embryos (44.4% and 46.7%). However, fertilization rates and percentage of transferable embryos were affected (P < 0.05) by period and donor. In conclusion, superstimulated donor cows inseminated four times had fewer Grade 1 embryos and more unfertilized ova with sexed versus conventional semen.     

A novel nitroxide is an effective brain redox imaging contrast agent and in vivo radioprotector

Individuals are exposed to ionizing radiation during medical procedures and nuclear disasters, and this exposure can be carcinogenic, toxic, and sometimes fatal. Drugs that protect individuals from the adverse effects of radiation may therefore be valuable countermeasures against the health risks of exposure. In the current study, the LD_50/30 (the dose resulting in 50% of exposed mice surviving 30 days after exposure) was determined in control C3H mice and mice treated with the nitroxide radioprotectors Tempol, 3-CP, 16c, 22c, and 23c. The pharmacokinetics of 22c and 23c were measured with magnetic resonance imaging (MRI) in the brain, blood, submandibular salivary gland, liver, muscle, tongue, and myocardium. It was found that 23c was the most effective radioprotector of the five studied: 23c increased the LD_50/30 in mice from 7.9 ± 0.15 Gy (treated with saline) to 11.47 ± 0.13 Gy (an increase of 45%). Additionally, MRI-based pharmacokinetic studies revealed that 23c is an effective redox imaging agent in the mouse brain, and that 23c may allow functional imaging of the myocardium. The data in this report suggest that 23c is currently the most potent known nitroxide radioprotector, and that it may also be useful as a contrast agent for functional imaging.     

Doping in sport—2. Quantification of the impurity 19-norandrostenedione in pharmaceutical preparations of norethisterone

The finding of measurable amounts of 19-norandrostenedione in norethisterone tablets prompted us to develop an assay to quantify this steroid. 19-Norandrostenedione is an anabolic steroid whose use in sport is prohibited by the World Anti-Doping Agency (WADA). The assay was developed using isotope dilution and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantification of 19-norandrostenedione in norethisterone formulations, with [3,4-¹³C₂]-19-norandrostenedione as the internal standard. The results showed amounts up to 1.01 ± 0.01 μg (mean ± S.E.M.) per tablet in those containing 5 mg of norethisterone or norethisterone acetate (0.02%, w/w) and up to 0.5 ± 0.01 μg (mean ± S.E.M.) per tablet (0.05%, w/w) in oral contraceptive tablets containing 0.35-1.5 mg of norethisterone or norethisterone acetate. No tablet tested exceeded the British Pharmacopoeia limit of 0.1% for this impurity.     

The potential benefits of nicaraven to protect against radiation-induced injury in hematopoietic stem/progenitor cells with relative low dose exposures

Nicaraven, a hydroxyl radical-specific scavenger has been demonstrated to attenuate radiation injury in hematopoietic stem cells with 5 Gy γ-ray exposures. We explored the effect and related mechanisms of nicaraven for protecting radiation injury induced by sequential exposures to a relatively lower dose γ-ray. C57BL/6 mice were given nicaraven or placebo within 30 min before exposure to 50 mGy γ-ray daily for 30 days in sequences (cumulative dose of 1.5 Gy). Mice were victimized 24 h after the last radiation exposure, and the number, function and oxidative stress of hematopoietic stem cells were quantitatively estimated. We also compared the gene expression in these purified stem cells from mice received nicaraven and placebo treatment. Nicaraven increased the number of c-kit⁺ stem/progenitor cells in bone marrow and peripheral blood, with a recovery rate around 60–90% of age-matched non-irradiated healthy mice. The potency of colony forming from hematopoietic stem/progenitor cells as indicator of function was completely protected with nicaraven treatment. Furthermore, nicaraven treatment changed the expression of many genes associated to DNA repair, inflammatory response, and immunomodulation in c-kit⁺ stem/progenitor cells. Nicaraven effectively protected against damages of hematopoietic stem/progenitor cells induced by sequential exposures to a relatively low dose radiation, via complex mechanisms.     

Copper toxicity in gibel carp Carassius auratus gibelio: Importance of sodium and glycogen

In general, copper is primarily an osmoregulatory toxicant to fish and Cu toxicity is thought to be related to the rate of sodium loss. Looking at a previous research it is striking that gibel carp, Carassius auratus gibelio, do not seem so susceptible to the first ionoregulatory shock phase of Cu exposure, but rather build up physiological disturbances slowly until mortality occurs. Since it was noted that gibel carp experience severe hypoxia under Cu exposure, we hypothesised that, besides the Na loss, the slow depletion of liver glycogen stores contributed equally to the collapse of physiological integrity. It is clear from our results that glycogen stores are being depleted in Cu exposed fish and that dead fish suffered more extensive glycogen losses compared to surviving fish, with liver glycogen levels of 125 ± 8 mg g⁻¹ in dead fish compared to 230 ± 13 mg g⁻¹ in surviving fish. However, changes in liver glycogen did not contribute significantly to mortality, while changes in whole body sodium and the rate of sodium loss did. Whole body Na levels dropped from 1111 ± 48 μg g⁻¹ dry weight in control fish to 850 ± 54 μg g⁻¹ in surviving fish and to 607 ± 24 μg g^− 1 in fish that had died resulting in Na loss rates of 1.25 ± 0.22 μg g^− 1 h^− 1 and 3.39 ± 0.19 μg g^− 1 h^− 1 in surviving and dead fish respectively. Our results support the finding that the rate of Na loss largely determines Cu toxicity in fish, even in resistant species.     

Testis stereology, seminiferous epithelium cycle length, and daily sperm production in the ocelot (Leopardus pardalis)

Similar to most wild felids, the ocelot (Leopardus pardalis) is an endangered species. However, knowledge regarding reproductive biology of the ocelot is very limited. Germ cell transplantation is an effective technique for investigating spermatogenesis and stem cell biology in mammals, and the morphologic characterization of germ cells and knowledge of cycle length are potential tools for tracking the development of transplanted germ cells. Our goal was to investigate basic aspects related to testis structure, particularly spermatogenesis, in the ocelot. Four adult males were used. After unilateral orchiectomy, testis samples were routinely prepared for histologic, stereologic, and autoradiographic analyses. Testis weight and the gonadosomatic index were 11 ± 0.6 g and 0.16 ± 0.01%, respectively, whereas the volume density of seminiferous tubules and Leydig cells was 83.2 ± 1.6% and 9.8 ± 1.5%. Based on the acrosomic system, eight stages of spermatogenesis were characterized, and germ cell morphology was very similar to that of domestic cats. Each spermatogenic cycle lasted 12.5 ± 0.4 d, and the entire spermatogenic process lasted 56.3 ± 1.9 d. Individual Leydig cell volume was 2522 μm³, whereas the number of Leydig and Sertoli cells per gram of testis was 38 ± 5 × 10⁶ and 46 ± 3 × 10⁶. Approximately 4.5 spermatids were found per Sertoli cell, whereas daily sperm production per gram of testis was 18.3 ± 1 × 10⁶, slightly higher than values reported for other felids. The knowledge obtained in this study could be very useful to the preservation of the ocelot using domestic cat testes to generate and propagate the ocelot genome.     

Treatment technique evolution and dosimetry trends over seven years of low dose rate prostate brachytherapy at an Australian institution

Low dose rate prostate brachytherapy treatments began at the Royal Adelaide Hospital (RAH), Australia, in September 2004. This paper will focus on the evolution of treatment technique since then showing how procedural improvements have enabled timely diagnosis of under-dose and scheduling of top-up treatments for sub-optimum implants, and how significant time savings have been achieved for staff and patients. In addition, implant dosimetry trends over this period have been investigated and results are presented. Iodine-125 seeds (Oncura model 6711) have been used since LDR prostate treatments began, with an aim to deliver a prostate dose of 145 Gy. Three key changes in implant technique took place during the period Sept 2004 to Sept 2011. The live implant dosimetry trends of the prostate D90, urethra V150, and rectum D0.1cc and D2.0cc, were assessed to see if the change in technique had an impact on the treatment planning and seed deployment. The switch from manual loading of seeds to pre-loaded needles and the change from a two-step pre-planning procedure to live planning have realized the greatest time savings with approximately 1.0 FTE physicist day saved per 2 patient implant day and 2 patient visits saved per treatment. Dosimetric parameters also improved with mean implant D90s rising from 166 Gy to 180 Gy. The average Urethra D10 also increased over the study group, rising from 186 Gy to 199 Gy while the rectum dose remained unchanged. Both rectum and urethra dose remained below GEC-ESTRO guidelines despite the observed rise in urethral dose.     

Initial synthesis and characterization of an immobilized heat shock protein 90 column for online determination of binding affinities

Heat shock protein 90α (Hsp90α) was immobilized on aminopropyl silica via the N terminus to create the Hsp90α(NT) column or via the C terminus to create the Hsp90α(CT) column. Binding to the exposed C terminus on the Hsp90α(NT) column was characterized using frontal chromatography and the C-terminus ligands coumermycin A₁ (CA1) and novobiocin (NOVO). The calculated K_d values were 220 ± 110 nM (CA1) and 100 ± 20 nM (NOVO). Nonlinear chromatography was used to determine the association and dissociation rate constants associated with the NOVO-Hsp90α complex: 22.2 ± 8.8 μM⁻¹ s⁻¹ and 2.7 ± 0.6 s⁻¹, respectively. Binding to the exposed N terminus on the Hsp90α(CT) column was characterized using frontal chromatography. The K_d values of the N-terminus ligands geldanamycin (GM, 90 ± 50 nM), 17-allylamino-17-demethoxygeldanamycin (17-AAG, 210 ± 50 nM), and radicicol (RAD, 20 ± 9 nM) were consistent with previously reported values. The effect of the immobilization on ATPase activity was investigated through the determination of IC₅₀ values for inhibition of ATPase activity on the Hsp90α(CT) column. The IC₅₀ for GM was 2.80 ± 0.18 μM, and the relative IC₅₀ values were 17-AAG > GM > RAD, in agreement with previously reported values and indicating that immobilization had not affected ATPase activity or sensitivity to inhibition.     

Évaluation du contenu surrénalien en androstènedione et effets de la castration chez le lapin domestique (Oryctolagus cuniculus)

DHEA, DHEA sulphate and androstenedione are C19 steroïds secreted by the adrenal cortex. These hormones with a weak androgen activity are precursors of estrogens and androgens. In human and other primates these hormones are produced in important quantities, even though, in domestic and laboratory animals, a few secretion is measured. In this survey, the androstenedione is quantified both in plasma and adrenal gland of young, prepubertal and adult rabbits and the castration effects on adrenal cortex histology are noted too. The absolute weight (AW) of the left adrenal gland is slightly higher than the right (p > 0.05) for all animals and the gland absolute weight (AW) for the adult rabbit is superior to the young and prepubertal rabitts (p < 0.05). The castration effect in adult increases the adrenal weight (p < 0.001). A zonation of adrenal cortex for young rabbits is observed. The zona fasciculata is important for young and prepubertal rabbits whereas, the zona reticularis is thicker for the adults. Thickness of glomerulosa, fasciculata and reticularis zonas increased with 6.55% (p > 0.05), 15.9% (p < 0.01) and 79.21% (p < 0.001) for the castred adult rabbits and histological modifications were observed in the zona reticularis. The plasma androstenedione is negligible for the young (0.060 ± 0.01 ng/mL), weak for the prepubertal (0.152 ± 0.03 ng/mL) and reaches (0.263 ± 0.03 ng/mL) for the adult. The androstenedione relative content (ng/100 mg of adrenal weight) is 2.90 ± 0.30; 4.54 ± 0.82 and 1.34 ± 0.36 for the young, prepubertal and adult rabbits. In this work, an increase of the androstenedione adrenal content is observed for the prepubertal rabbits, which could intervene in the process of puberty.     

Quality evaluation of umbilical cord blood progenitor cells cryopreserved with a small-scale automated liquid nitrogen system

The performance of a small-scale automated cryopreservation and storage system (Mini-BioArchive system) used in the banking of umbilical cord blood (UCB) units was evaluated. After thawing the units, the viability and recovery of cells, as well as the recovery rate of hematopoietic progenitor cells (HPCs) such as CD34⁺ cells, colony-forming unit-granulocyte-macrophage (CFU-GM), and total CFU were analyzed. Twenty UCB units cryopreserved using the automated system and stored for a median of 34 days were analyzed. Mean CD34⁺ cell viabilities before freezing were 99.8 ± 0.5% and after thawing were 99.8 ± 0.4% in the large bag compartments and 99.7 ± 0.5% in the small compartments. The mean recovery values for total nucleated cells, CD34⁺ cells, CFU-GM, and total CFU were 94.8 ± 16.0%, 99.3 ± 18.6%, 103.9 ± 20.6%, and 94.3 ± 12.5%, respectively in the large compartments, and 95.8 ± 25.9%, 106.8 ± 23.9%, 101.3 ± 23.3%, and 93.8 ± 19.2%, respectively in the small compartments. A small-scale automated cryopreservation and storage system did not impair the clonogenic capacity of UCB HPCs. This cryopreservation system could provide cellular products adequate for UCB banking and HPC transplantation.     

A sublethal dose of thiamethoxam causes a reduction in xylem feeding by the bird cherry-oat aphid (Rhopalosiphum padi), which is associated with dehydration and reduced performance

The active ingestion of xylem sap by aphids is hypothesised to be an important mechanism for rehydration. When starved bird cherry-oat aphids (Rhopalosiphum padi) were allowed to feed on wheat (Triticum aestivum) treated with a sublethal dose of the xylem-mobile neonicotinoid thiamethoxam, analysis of feeding behaviours using the electrical penetration graph revealed a reduction in xylem feeding that was reversed on removal of the toxin. To test the importance of xylem-feeding behaviour as a rehydration mechanism, the effects of the sublethal dose of thiamethoxam on aphid water content, honeydew excretion, growth and fecundity were investigated. Body water contents of starved R. padi feeding on wheat treated with thiamethoxam were significantly reduced compared to aphids feeding on wheat treated with distilled water (74.5 ± 0.23 and 75.6 ± 0.18%, respectively). In addition, the sublethal dose of thiamethoxam had detrimental effects on aphid performance. At reproductive maturity, aphids that had been born on wheat treated with thiamethoxam were significantly smaller (as measured by body plan area; 1.07 ± 0.03 mm²), lighter (0.31 ± 0.04 mg) and less fecund (2.85 ± 0.36 nymphs/day) than aphids born on wheat treated with distilled water (1.87 ± 0.02 mm², 0.72 ± 0.03 mg, 11.28 ± 0.58 nymphs/day, respectively). Regardless of whether the observed impairment of xylem feeding is due to a neurotoxic or an antifeedant effect, these results have important implications for commercial crop protection as the behaviour-modifying effects of the sublethal dose of thiamethoxam may change the efficacy of this pesticide throughout the growing season.     

Comparison of two different cryopreservation protocols for freezing goat semen

In this study, two different semen cryopreservation protocols were compared to freeze goat semen. The ejaculates (n = 12) were collected by using electro-ejaculator from six mature bucks (two ejaculates per each buck). Each ejaculate was divided into two groups as Protocol 1 (P1) and Protocol 2 (P2). In P1, semen was diluted directly in an extender containing 15% egg yolk, 300 mM Tris, 28 mM glucose, 95 mM citric acid 5% glycerol to a concentration of 200 × 10⁶ sperm/mL. In P2, after the removal of seminal plasma by centrifugation, the semen sample was diluted with the first portion of milk extender consist of 100 mg/mL skimmed milk powder and 27.75 mM glucose (without glycerol) to a concentration of 400 × 10⁶ sperm/mL. The second portion of the milk extender containing 14% glycerol was added to semen gradually in order to achieve sperm concentration 200 × 10⁶ sperm/mL and 7% glycerol level in the final volume. Extended semen was loaded in 0.25 mL straws, held for 2 h at 4 °C, frozen in nitrogen vapor and stored in liquid nitrogen. Post-thaw motility and live sperm rate (mean ± SEM) were significantly lower (P < 0.05) in P1 as compared to P2 (47.50 ± 1.23% vs. 55.63 ± 1.72%; 80.04 ± 1.29% vs. 84.04 ± 1.08%, respectively). However, live intact, total intact, abnormal, reacted acrosome and DNA damaged sperm rates were similar (P > 0.05) in both protocols. It was concluded that both protocols used in this study provided reasonable post-thaw parameters; however, P2 yielded better motility and live sperm rate compared to P1.     

Improvement in buffalo (Bubalus bubalis) spermatozoa functional parameters and fertility in vitro: Effect of insulin-like growth factor-I

The aim of the current study was to assess the effect of insulin-like growth factor-I (IGF-I; 100 ng/mL) on buffalo (Bubalus Bubalis) sperm functional parameters related to in vitro fertilization. The acrosin activity (the mean diameter of halo formation in micrometers) was significantly higher in the IGF-I group (14.17 ± 1.51) compared with that in the control group (9.50 ± 0.36) at 2 h incubation. The mitochondrial membrane potential (per cent) was significantly higher in the IGF-I group compared with that in the control group at 30 min (33.27 ± 2.62 vs. 26.71 ± 1.02), 60 min (24.24 ± 3.45 vs. 18.77 ± 2.09), and 90 min (22.86 ± 3.02 vs. 16.92 ± 1.24) incubation. The percentage of spermatozoa positive for sperm nuclear chromatin decondensation (NCD) differed significantly between the groups at 90 and 120 min incubation. The comet length was significantly lower in the IGF-I group compared with that in the control group at 2 h incubation. The percentage of fragmented DNA in the tail did not differ significantly between the groups at 2 h incubation. The percentage of acrosomal-reacted spermatozoa did not differ significantly between the IGF-I and the control groups at 4 h (41.12 ± 6.44 vs. 43.53 ± 5.05) incubation. The cleavage rate (per cent) was significantly higher in the IGF-I-treated group (56.73 ± 3.70) compared with that in the control group (44.85 ± 2.15). The current study suggests that the addition of IGF-I prevents deterioration of sperm functional parameters and fertility.     

Lambing rates and litter size following carazolol administration prior to insemination in Kivircik ewes

The effect of carazolol on the ease of penetrating the cervix during artificial insemination, lambing rate and litter size was studied using 1.5–4.0-year old Kivircik ewes in an incomplete 3 × 2 × 2 experimental design. All of the ewes in this study were synchronized for oestrus by insertion of a progesterone impregnated vaginal sponge for 12 days and administration of 400 IU PMSG at sponge withdrawal. Three methods of service were compared: natural service, artificial insemination (AI) with fresh semen, or AI with frozen semen. Two times of insemination (fixed time AI versus AI at observed oestrus) were compared on the fresh and frozen AI treatments. The absence (control) or use of carazolol (carazolol; 0.5 mg/ewe i.m. 30 min before mating) was the third factor in the design and penetration of the cervix by the insemination pipette was assessed as shallow (<10 mm), middle (10–20 mm) or deep (>20 mm). Natural service ewes were only mated at observed oestrus. Consequently, the factorial design was incomplete and there were a total of 10 treatments each represented by 30 ewes. Natural service resulted in a significantly (P < 0.05) higher lambing rate and litter size (86%; 2.0 ± 0.05 lambs/ewe) than AI using fresh (65%; 1.6 ± 0.1 lambs/ewe) or frozen (40%; 1.4 ± 0.14 lambs/ewe) semen. For AI animals the lambing rate and litter size were not significantly different when service was at a fixed time (50%; 1.5 ± 0.12 lambs/ewe) or at observed oestrus (56%; 1.5 ± 0.12 lambs/ewe). Carazolol did not permit complete cervical penetration in any ewe. Deep penetration of the cervix at AI was achieved in 33% of untreated (control) and 48% of carazolol treated ewes (P < 0.05). However, the proportion of ewes in which penetration of the cervix and semen deposition was greater than shallow was similar for control (82%) and carazolol (85%), and lambing rate and litter size were similar for both treatments. Over the three service methods, the lambing rate was 56% for control and 63% for carazolol (NS) and litter size was similar for both treatments. It was concluded that the carazolol treatment used prior to natural mating or AI in this experiment did not improve lambing rate or litter size in Kivircik ewes.