Influence of Nano-Methionine supplementation in drinking water on growth performance, lipid metabolism, and related gene expression in broiler chicken

Objectives

The study aimed to determine how Nano-Methionine (Nano-Meth) affected growth, lipid metabolism, and relative gene expression for acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), growth hormone receptor (GHR), insulin-like growth factor receptor-1 (IGFR-1), myostatin (MSTN), and cholecystokinin (CCK) genes in broiler chickens.

Materials and Methods

A total of 100 1-day-old broilers were randomly assigned into 2 groups: 1) the control group received drinking water without any supplements, and 2) the Nano-Meth group received 10 ml/l of 5% Nano-Meth starting from 1 day old until 35 days old (the end of the experiment).

Results

Nano-Meth improved final body weight, weight gains, feed intake, and feed conversion ratio. Compared to the control group, Nano-Meth significantly lowered the serum levels of triglyceride, cholesterol, very low-density lipoprotein, and low-density lipoprotein in chickens. Nano-Meth significantly increased the serum levels of total protein, albumin, high-density lipoprotein, and glucose more than the control group. Nano-Meth lowered the mRNA gene expression of ACC, FAS, MSTN, and CCK but increased that of GHR and IGFR-1.

Conclusions

We concluded that supplementation with Nano-Meth enhances growth performance and decreases lipid accumulation in broiler chickens.

Effect of follicular ablation and gonadotropin priming on the recovery and quality of oocytes in Boran cows

The objective of the study was to evaluate the effect of follicle ablation, exogenous FSH application, and different coasting time prior to ovum pick-up (OPU) on the number of follicles suitable for aspiration, oocyte quality, and cleavage rate in Ethiopian Boran cows. The experiment was carried out in three parts, (I) cows were synchronized using 500 µg PGF2α given 11 days apart. Cows were then subjected to a biweekly ovum pickup session before ovulation (n = 5) or starting day 7 after ovulation (n = 4) for 3 weeks. (II) Cows were synchronized, and all visible follicles were ablated on the first days of overt estrus, and cows were grouped into those that received a divided dose of 350 IU FSH (n = 5) or 175 IU FSH (n = 5) over 3 days. In both groups, OPU was carried out weekly starting 48 h after the last FSH for 6 weeks. (III) Protocol was similar to part II, but in group with 350 IU FSH (n = 5), coasting period was increased to 72 h. The covariates of follicles and oocyte were not affected (P > 0.05) by corpus luteum presence at OPU. The mean number of medium (7.36 ± 0.57) and large (8.28 ± 0.96) follicles were significantly higher (P < 0.05) in the group that received divided 350 IU FSH. Similarly, the mean number of grade-1 (4.19 ± 0.24) and grade-2 (4.32 ± .27) oocytes, maturation rate (70.41%), and cleavage rate (47.5%) were significantly higher (P < 0.05) in the group that received 350 IU FSH. COC quality was significantly (P < 0.05) influenced by coasting period. However, both maturation and cleavage rates were not affected by the coasting period. This study demonstrated that follicular ablation and treatment with FSH improves follicular population and oocyte recovery rate in Boran cows.

Dietary supplementation of nano-selenium eliminates the negative effects of long-term ivermectin injection on growth and reproductive performance of female rabbits

Objective:

We investigated the effects of a source of selenium [inorganic or nano-selenium (nano-Se)] on female V-line rabbits with or without injection of ivermectin (IVM).

Material and Methods:

Eighty four rabbits (12 weeks old) were randomly divided into 4 groups of 21 rabbits each with the basal diet supplemented as per the following treatments: G1 (control): inorganic Se at 0.3 mg/kg diet with no IVM injection; G2: inorganic Se with IVM injection; G3: nano-Se with no IVM injection; and G4: nano-Se with IVM injection. IVM was injected subcutaneously at 0.2 mg/kg body weight starting when the does were 14 weeks old and repeated weekly for five consecutive weeks.

Results:

Replacement of inorganic Se with nano-Se improved body weight and total body weight gain, total feed intake, average feed conversion ratio, and reproductive performance (age at puberty, number of service/conception, conception rate, number of kits/litter, and litter weight at birth). Similarly, sexual activity of does, serum estrogen levels, and serum levels of antioxidants (glutathione reduced, catalase, and malondialdehyde) increased in nano-Se-supplemented groups. Ivermectin treatment in inorganic Se-supplemented groups was detrimental to growth and reproductive performance, while these parameters improved in IVM-treated and nano-Se-supplemented groups.

Conclusion:

Nano-Se mitigated the negative effects of IVM treatment on the growth and reproductive performance of does.

Dietary supplementation of nano-selenium improves reproductive performance, sexual behavior and deposition of selenium in the testis and ovary of Japanese quail

Objective

Selenium (Se), as the form of selenite, is commonly supplemented in poultry diet, which has low bioavailability and high toxicity. Here, we compared the effects of the supplementation of the diet with Se nanoparticles (nano-Se) on the growth, sexual behavior, and reproductive performance (gonad size, sperm quality traits, and plasma testosterone levels for males and egg production for females) of Japanese quail (Coturnix coturnix japonica).

Materials and Methods

Quail chicks (n = 300) aging 14 days were divided into three groups: Group 1 (basal diet and Se at 0.2 mg/kg ration), Group 2 (basal diet and nano-Se at 0.2 mg/kg ration), and Group 3 (basal diet and nano-Se at 0.1 mg/kg ration). Several parameters relating to body weight and egg were measured. Sexual behaviors of the birds were observed by continuous visual scanning. The sperm viability, sperm morphology, and concentration of spermatozoa were determined after staining and microscopic examination. The plasma testosterone levels were determined by indirect enzyme immunoassay assay. The Se concentrations in the testicular, ovarian, and ration samples were measured by flame emission atomic absorption spectrophotometer.

Results

The type or concentration of nano-Se administration had no impact on body weight, feed efficiency, egg production, or egg weight. However, the total feed intake throughout the experiment was reduced in Group 2 at 0.2 mg/kg. Nano-Se supplementation significantly increased the sexual behavior. In general, the deposition of Se in the testicular and ovarian tissues increased with increasing supplement concentration. At the same supplement concentration, the tissue deposition of nano-Se was more enhanced than that of inorganic Se. Nano-Se supplementation improved the testicular functions by enhancing plasma testosterone level and sperm quality traits (sperm count, motility, and viability). This improvement was found more prominent with the lower supplement concentration (when comparing 0.1 vs. 0.2 mg/kg diet).

Conclusion

It is concluded that the use of nano-Se (at 0.1 mg/kg) in the ration of Japanese quail improves several reproductive performance parameters.

175 EFFECT OF ACETYL-CoA CARBOXYLASE (ACC) INHIBITOR ON THE LIPID CONTENT AND NUCLEAR MATURATION OF CANINE OOCYTES

Compared with other domestic species, embryo technologies are least developed for the dog. This is mainly due to difficulties in producing mature oocytes in vitro. Canine oocytes contain exceptionally high amounts of lipid. High lipid content increases the chilling sensitivity of oocytes and embryos. Mechanical and chemical reductions of the lipid content have been used to improve the cryotolerance of oocytes. Additionally, chemical stimulation of lipid catabolism improved oocyte in vitro maturation (IVM) rates in other species (You et al. 2012 Theriogenology 78, 235–543). Acetyl-CoA carboxylase (ACC) is the rate-limiting enzyme in de novo lipogenesis and its expression has been reported in oocytes and embryos. In somatic cells, inhibition of ACC reduces lipogenesis and enhances β-oxidation. Our hypothesis is that treatment of oocytes with an inhibitor of ACC (CP640186, Pfizer Animal Health, New York, NY, USA) reduces lipid content and improves IVM rate of oocytes. Ovaries were collected from a spay clinic and sliced in HEPES-buffered TCM-199 to recover oocytes. In vitro maturation was conducted at 38.5°C, 5% CO2, and high humidity in TCM-199 supplemented with 1% fetal bovine serum, glutamine, sodium pyruvate, β-mercaptoethanol, oestradiol, epidermal growth factor, and antimicrobial agents (Songsasen et al. Mol. Reprod. Dev. 79, 186–196). During the first 19 to 21 h, the IVM media contained 4 concentrations of the inhibitor (0+DMSO, 0.02, 0.1, and 0.5 μM, designated as treatments 1, 2, 3, and 4, respectively) and then oocytes were transferred to a medium without the inhibitor and cultured for an additional 27 to 29 h. At the end of culture (total of 48 h), oocytes were denuded of cumulus layers, washed, fixed, and stained with Nile red (lipid) and Hoechst-33342 (chromatin), and then mounted on a microscope slide. Lipid content and chromatin status were evaluated using fluorescent microscopy (TRITC and DAPI filters, respectively). The relative lipid content was measured by the corrected total cell fluorescence (CTCF) using ImageJ software (http://rsbweb.nih.gov/ij/). Data on CTCF and proportions of chromatin status of oocytes were analysed using one-way ANOVA (SigmaPlot 11.0). The mean CTCF for each treatment was 5.5 × 109 (n = 51, 5.2 × 109 (n = 44), 4.5 × 109 (n = 31), and 4.8 × 109 (n = 34), respectively (P = 0.3; 4 replicates). At the highest dose, the agent induced relatively more cumulus cell layer expansion but inhibited their attachment to the dish; the latter effect was reversible because cumulus cells attached and proliferated after washing the oocytes of the agent. Metaphase II was rare (≤3.1%); however, the proportion of oocytes developing to ≥GVBD stage (Trt 1 14%, n = 37; Trt 2 41%, n = 56; Trt 3 5%, n = 22; Trt 4 11%, n = 43) was affected by treatments. Our preliminary data indicate that a low concentration of ACC inhibitor has a positive effect on the nuclear maturation of canine oocytes but the effect on lipid content as estimated by using Nile red fluorescence intensity appears to be minimal.

144 EXPRESSION OF ACETYL COENZYME A CARBOXYLASE α (ACCα) IN FELINE, CANINE AND PORCINE OOCYTES

High lipid content in in vitro–derived embryos of several species is associated with poor developmental potential and cryosurvival of oocytes. Lipid content of oocytes varies among species and embryonic lipid content is further influenced by the culture environment. In spite of the variation among species, the relative contribution of de novo lipid synthesis during oocyte maturation or subsequent embryonic development is unknown. In the present study, we evaluated the expression of acetyl coenzyme A carboxylase (ACCα), the key rate-limiting enzyme of lipogenesis, in oocytes of 3 species with high lipid content. Ovaries of dogs and cats were collected from a local veterinary clinic and those of pigs from an abattoir. Cat and dog oocytes were recovered by the slicing method of the ovaries. Porcine oocytes were recovered by aspiration of ovarian follicles. Immediately after collection, oocytes were fixed for 30 min using a solution of 10% neutral buffered formalin. The ACCα enzyme expression was evaluated in porcine, cat and dog oocytes by immunofluorescence using a goat anti-human ACCα primary antibody followed by fluorescein isothiocyanate-conjugated anti-goat secondary antibody. The study was replicated, with negative controls, 3 times using ≥30 oocytes per species. Messenger RNA expression of ACCα gene was also evaluated in pig oocytes. The RNA was isolated from fat tissue, pooled good-quality oocytes (n = 30), pooled poor-quality oocytes (n = 30) and cumulus cells using the RNeasy Micro kit (Qiagen, Valencia, CA, USA) according to the manufacturer's instructions. Complementary DNA was synthesised from 200 ng of RNA using Quantitect reverse-transcription kit (Qiagen) according to the manufacturer's instructions. Real-time PCR assays were carried out in duplicate and expression of ACCα mRNA levels relative to fat was determined. Oocytes and cumulus investment in cats, dogs and pigs strongly expressed ACCα. Expression of the protein was uniformly distributed through the entire ooplasm. The mRNA expression of ACCα in good- and poor-quality oocytes and cumulus cells relative to fat tissue was 11.5, 1.4 and 40.1%, respectively. Further studies are warranted on the dynamics of expression of ACC during in vitro maturation and the functional activity of the enzyme. We extend our appreciation to the Alabama Animal Alliance Inc. (Montgomery) for providing us with dog and cat ovaries; the Lambert-Powell Meats Laboratory of Auburn University for donating pig ovaries; and Dr. James Webster, Dr. Tsegaye Habtemariam and Dr. Abdalla Eljack for administrative support.

201 ENDOSCOPE-GUIDED TRANSFER OF SPERM-INJECTED OOCYTES INTO THE OVIDUCTS OF ELAND AND BONGO ANTELOPES

We have previously established methods of gamete collection in Eland and Bongo antelopes; however, blastocyst development following IVF, intracytoplasmic sperm injection (ICSI), or somatic cell nuclear transfer (SCNT) has been sporadic, thus few developmentally competent embryos have been produced for uterine transfer. In the present study, we evaluated the possibility of oviductal transfer of presumptive zygotes. Estrous cycle synchronization and ovarian superstimulation were done as follows. Females were treated with altrenogest (0.11 g/os daily) for 7 days. The FSH Folltropin® was dissolved in 30% polyvinylpyrrolidone and administered, i.m. on Days 5 and 7 of altrenogest treatment at 266 mg and 134 mg, respectively. Prostaglandin F2α (Lutalyse®, 25 mg, i.m.) was administered on Day 7. Transvaginal ultrasound-guided oocyte retrieval was conducted on Day 9 as described previously (Wirtu G et al. 2009 Anim. Reprod Sci. 111, 160-172). Eleven oocytes were recovered from 2 Elands and 4 from 1 Bongo. One oocyte of each species was degenerate at the time of recovery. Oocytes were subjected to IVM for approximately 22 h, when Piezo drill-assisted ICSI was done using frozen-thawed Eland or Bongo spermatozoa. Oocytes were activated (5% ethanol, 5 min) and cultured overnight in CR1aa medium supplemented with BSA. Presumptive zygotes were subjected to endoscopic oviductal transfer at 21 to 24 h after ICSI. The oviductal transfer was adapted from the technique developed in domestic cattle (Wetscher F et al. 2005 Theriogenology 64, 30-40). Animals were sedated by i.m. administration of xylazine HCl and butorphanol tartrate and restrained in a hydraulic chute (Tamer®) that was used to squeeze and lift the females. An epidural block (5 mL of lidocaine) was induced after cleaning the rectum, perineal region, and the injection site. A uterine relaxant, isoxsuprine HCl (10 mg, i.v), was then administered. The Brem/Besenfelder set for laparoscopic bovine embryo transfer (Karl Storz Endoscope, Karl Storz GmbH & Co. KG, Tuttlingen, Germany) was used for the oviductal transfer. Briefly, a cannula (12.5 mm in diameter, 49.5 cm long) fitted with a blunt-tip obturator was introduced into the vagina and positioned, during transrectal manipulation, at the mid-dorsal aspect of the vaginal vault. The blunt-tip obturator was replaced with a sharp-tip obturator, which was used to puncture through the vaginal wall for entry into the pelvic cavity. The trocar was subsequently replaced with an inner sheath containing a telescope (5.5 mm in diameter, 54 cm long) and a pre-loaded transfer tubing. Visualization of the ovaries and oviducts required insufflation of the peritoneal cavity. Transfer was done into the oviduct ipsilateral to the recently ovulating ovary. Ten Eland oocytes had extruded the first polar body and 8 that survived ICSI were transferred into the right oviduct of an Eland female. Two Bongo oocytes had extruded the first polar body; both survived ICSI and were transferred to the right oviduct of a Bongo female. Pregnancy diagnosis is pending. This minimally invasive method of accessing the oviduct has the potential to advance the application of assisted reproductive technologies in large nondomestic ungulates.

169 BEHAVIORAL ASPECTS OF ESTRUS IN THE COMMON ELAND ANTELOPE, TAUROTRAGUS ORYX

Knowledge of the estrous cycle and behavior is important in managing captive breeding programs. However, such information is negligible in spiral-horned antelopes, including the eland. In the present study, conducted between September 2007 and March 2008, we sought to characterize mounting activity and courtship behavior in a group of eight adult eland females. Estrus was induced in groups of four females by treatment with 25 mg PGF2 ∝ (IM, Lutalyse®, Pharmacia and Upjohn Company, Kalamazoo, MI, USA) administered after 7 days of daily oral progestin (5 mL of 2.2% altrenogest, DPT Laboratories, San Antonio, TX, USA) or 11 days after an initial treatment of PGF2 ∝ (25 mg). The eight females received each treatment in a crossover design. Females were induced and monitored during the induced and subsequent natural estrus for 34 to 38 days. Observations for estrus behavior were initially assisted by using Estrotect™ heat detector patches (Rockyway, Inc., www.estrotect.com). Since January 2008, the HeatWatch® electronic heat detection system (CowChips, Denver, CO, USA) and an androgenized eland female were used to assist with heat detection. For androgenization, 8 pellets of Synovex-H® (Fort Dodge Animal Health, Fort Dodge, IA) comprising a total dose of 1600 mg testosterone propionate and 160 mg estradiol benzoate were implanted (SC) on the convex side of the ear. To confirm mounting activity detected by Estrotect™ or HeatWatch®, eland behavior was recorded continuously using an 8-channel real time DVR. Chi-square analysis was used to test the association between time of day (day or night) and the frequency of standing to be mounted. The cycle length (n = 6 females) was the time interval (d) between the first mounts at the induced and natural estrus. The time of mounts was determined for a total of 52 mounts. More than half of the mounts (n = 32 or 61.5%) occurred between 6 pm and 6 am (night); however, there was no association between the number of mounts and time of the day (p = 0.886). Analysis of mounts by quarters of the day showed that mounts were evenly distributed between early afternoon (noon to 6 pm: 29%), late afternoon (6 pm to midnight: 33%) and early morning (midnight to 6 am: 29%) but were less frequent during late morning, between 6 am and noon (10%) possibly due to interference by human activities. The number of mounts observed per female ranged from 1 to 20. Mounts lasted for 2 seconds or less. The duration of estrus ranged from 2.1 to 29.0 hours. Typical courtship behaviors included prolonged head butting, flehmen response and following the female in estrus before mounting. The average length of the estrous cycle, based on mounting activities, was 19.3 d (range: 17–24). Although further studies are required in herds with eland males, the present results suggest that estrus detection for captive breeding or application of reproductive technologies in the eland should be spread around different times of the day and night. We have also demonstrated that an electronic mount detection system can be applied to assist with determination of estrus in the eland.

23 EFFECT OF HISTONE ACETYLATION LEVELS ON THE IN VITRO DEVELOPMENT OF CLONED BOVINE EMBRYOS

The epigenetic status of donor cells is an important factor for their successful reprogramming during somatic cell nuclear transfer (SCNT). Environmental factors partly influence DNA methylation and histone modifications (Fraga et al. 2005 PNAS USA 102, 10 604–10 609; Ke et al. 2006 Carcinogenesis 27, 1481–1488; Rodenhiser and Mann 2006 CMAJ 174, 341–348); low temperatures have altered epigenetic events in plants (Amasino 2004 Plant Cell; Hao et al. 2002 Cryo Letters 23, 37–46). Because cryopreservation alters histone acetylation levels in donor cells and subsequent viability of cloned embryos (Gómez et al. 2008 Cloning Stem Cells, in press), similar alterations may occur in bovine cloned embryos reconstructed with donor cells thawed immediately before SCNT. The objectives of the present study were (1) to measure the relative levels of nuclear histone acetylation in bovine fibroblasts immediately after thawing (frozen/thawed) or following a period of culturing (cultured) and (2) to determine the influence of the epigenetic status of donor cells on the in vitro development of reconstructed, cloned bovine embryos by gauging blastocyst development. Cell cultures lines were derived from the skin of 3 adult cows and analyzed at passage 1 (P1), 2 (P2), and 10 (P10). For each of 3 passages, cells were cultured until reaching 100% confluence, followed by an additional 3 days of culture during which time acetylation levels were measured in cultured and frozen/thawed cells. For cryopreservation, cells at P1, P2, and P10 were disaggregated and resuspended in CryoStor™ (CS10; BioLife Solutions, Bothell, WA, USA) and cooled at 1.0°C min–1 to –80°C prior to storage in liquid nitrogen. Cells were fixed with ethanol for 12 h and incubated for 30 min with antibody directed against acetylated lysine 9 on histone 3 (H3K9). The cells were then incubated with a fluorescein isothiocyanate conjugated secondary antibody and DNA stain and evaluated by flow cytometry. Cloned embryos were reconstructed with cultured or frozen/thawed cells at P1, P2, and P10 as described by Vajta et al. 2005 (Reprod. Fertil. Dev. 17, 791–797). Derived embryos were cultured until Day 8, and cleavage and development to the blastocyst stage were evaluated. Histone acetylation levels for all 3 cell lines, either fresh or frozen/thawed, were significantly higher at P1 than at P2 and P10 (Table 1), and cryopreservation reduced histone acetylation levels only in cell culture line 2 at P1. Higher development to the blastocyst stage (25%) was observed when embryos were reconstructed with cultured cells at P2 and with cells that had lower histone acetylation levels (Pearson correlation, r = –0.55; P = 0.01) Table 1.Relative levels of histone acetylation in bovine fibroblast culture and percentages of development to blastocyst stage after cloning

164 CHARACTERIZATION OF THE COMMON ELAND (TAUROTRAGUS ORYX) ESTROUS CYCLE

Three species of Tragelaphine (spiral horned) antelopes are endangered including the Eastern Bongo. Though most antelope species are represented as captive herds, a detailed characterization of their estrous cycles has not been described. In a crossover experimental design utilizing two groups of four females (n = 8), two estrus synchronization treatments were applied to each female. The treatments were: 1) PGF2∝ (Lutalyse®, 25 mg IM) repeated 11 days later and 2) administration of a progestin (altrenogest, 5 mL, 2.2% p.o.) for 7 days followed by PGF2∝ (25 mg IM) on 7th day. Blood samples were collected three days (Monday, Wednesday and Friday) per week until 2 days before expected estrus when ovaries were examined via transrectal ultrasound once daily and blood samples were collected twice daily, until the dominant follicle was absent. Blood samples were then collected three days per week until two days before the predicted subsequent natural estrus, when intensive ultrasound and blood collection was resumed. Plasma progesterone levels were determined via competitive radioimmunoassay utilizing a double antibody system from a commercially available kit (Diagnostic Systems Laboratories, Webster, TX, USA). Progesterone levels declined in an equal number of females (n = 6 or 75%) following prostaglandin injection in treatments 1 and 2, suggesting both methods to synchronize the estrous cycle or induce estrus are equally effective. Five of the eight females ovulated at least once during the study. A total of eight (25%) of the 32 possible ovulations were detected by ultrasound observation and confirmed by progesterone levels. Basal progesterone levels for the ovulating females around the days of ovulation were approximately 0.5 ng mL–1 and peaked at approximately 2 ng mL–1 during the luteal phase. Ultrasound observed ovulations occurred as frequently on the right ovary as the left. Two animals from treatment 2 ovulated during both the induced and natural cycles on alternate ovaries. An interovulatory interval of 21 days was observed and agrees with data previously reported by Durrant (1983 Zoo Biol. 2, 191–197). The average time to ovulation after PGF2∝ injection was 69 h (range 58–82 h). The average follicular size 12 to 24 h prior to ovulation was 9 and 7 mm for the induced and natural ovulations, respectively, suggesting that eland follicles ovulate at 10 mm. The described technology allows hormonal and ultrasonographic characterization of the estrous cycle in the eland antelope.

Cloned embryos from semen. Part 1: in vitro proliferation of epithelial cells on embryonic fibroblasts after isolation from semen by gradient centrifugation

Although epithelial-like somatic cells have been previously isolated from semen, cell proliferation rates were low. Culture of whole semen samples resulted in loss of potentially valuable spermatozoa. The aims of the present study were to: (1) isolate somatic cells from semen, while preserving sperm viability, and (2) optimize in vitro culture conditions for semen-derived epithelial cells. Density gradient centrifugation of washed ejaculates of two rams (Ovis aries) (n = 24) and one eland bull (Taurotragus oryx) (n = 4) was performed using a three-layer discontinuous Percoll column consisting of 90% (P-90), 50% (P-50), and 20% (P-20) Percoll. In vitro culture and Trypan Blue staining indicated that live somatic cells settled in the P-20 layer. Nonmotile spermatozoa were recovered at the P-50 and P-90 interfaces, whereas motile spermatozoa were collected in the pellet from the P-90 layer. Subsequently, somatic cells isolated from the P-20 layer were plated either on inactivated 3T3 mouse embryonic fibroblast feeder layers, collagen-coated plates with 3T3 feeder cell inserts, or on collagen-coated plates. Initial somatic cell plating was similar among treatments, but proliferation significantly increased when cocultured with 3T3 cells (feeder or insert). Furthermore, two different types of epithelial cells were obtained. The exact origin of the cells in the male reproduction system is uncertain and probably variable. The present method of cell isolation and in vitro culture may be of value for preserving endangered species. Specifically, cells isolated and cultured from cryopreserved semen of nonliving males could be used for producing embryos by somatic cell nuclear transfer.

274 LYSOLECITHIN TREATMENT OF ELAND, BONGO, AND BOVINE SPERMATOZOA AND CLEAVAGE OF BOVINE OOCYTES AFTER INTERSPECIES INTRACYTOPLASMIC SPERM INJECTION

Compared to success rates in human, intracytoplasmic sperm injection (ICSI) is inefficient in ungulate species. Although factors such as injection of membrane-intact sperm and toxic effects of acrosome contents are suspected causes, the reasons for the inefficiency are unclear. A recent report in mice demonstrated that ICSI using spermatozoa treated with a physiological detergent, lysolecithin, improved oocyte activation, cleavage, and offspring production after embryo transfer (Morozumi K et al. 2006 PNAS 109, 17 661–17 666). The objectives of the present study were to evaluate the effects of detergent treatment on motility and membrane integrity of frozen thawed eland, bongo and bovine spermatozoa and to examine sperm decondensation/embryonic cleavage following ICSI of in vitro-matured bovine oocytes. In experiment 1, sperm motility was observed on a warm microscope stage during exposure to 3 lecithin concentrations, 0.04, 0.02, and 0.01%, and the time at which 100% of the spermatozoa lost motility was recorded. In experiment 2, spermatozoa were exposed to 0.02% lecithin for 22 s, and the membrane integrity and acrosome status of spermatozoa were determined using a combined trypan blue-Giemsa staining (Nagy et al. 1999 Theriogenology 52, 1153–1159). In experiment 3, bovine oocytes were injected, using the piezo drill, with lecithin-treated (0.02%, immobilized) or untreated (piezo pulse immobilized) eland, bongo, or bovine spermatozoa and subsequently cultured for 2 days in CR1aa containing 3 mg mL–1 BSA. Each experiment was replicated at least 3 times. Lecithin induced time- and concentration-dependent loss of sperm motility. The average time to loss of motility in 100% of the spermatozoa at 0.04, 0.02, and 0.01% lecithin was 107, 222, and 344 s in bovine; 82, 135, and 179 s in eland; and 65, 115, and 158 in bongo, respectively. Data on membrane integrity (intact or nonintact) and acrosome status (reacted or nonreacted) of detergent-treated or control spermatozoa are shown in Table 1. Sperm head decondensation and embryonic cleavage were observed following homologous and interspecies (antelope into bovine) ICSI of lecithin-treated or control spermatozoa. In conclusion, lecithin treatment induced concentration and time-dependent loss of motility and was effective in damaging the sperm membrane and acrosome in eland, bongo, and domestic bulls. Eland and bongo spermatozoa underwent decondensation and activated bovine oocytes after interspecies ICSI. Table 1.

25 CRYOPRESERVATION AND IN VITRO CULTURE AFFECT HISTONE ACETYLATION LEVELS OF BOVINE FIBROBLASTS

Long-term culture of bovine fibroblasts increases histone acetylation levels (Enright et al. 2003 Biol. Reprod. 69, 1525–1530), and blastocyst development and pregnancy rates are enhanced by using donor cells having high levels of histone acetylation (Yang et al. 2007 Reproduction 133, 219–230; Yang et al. 2006 Biol. Reprod. 76, 36–42). When histone acetylation levels are increased in amino acid residues, the nucleosome is less tightly bound to DNA and, as a consequence, relaxation of the chromatin structure occurs (Zlatanova et al. 2000 FASEB J. 14, 1697–1704). Exposure of the donor cell with relaxed chromatin structure to oocyte cytoplasm factors after nuclear transfer (NT) may be effective for nuclear reprogramming (Tóth et al. 2004 J. Cell Sci. 117, 4277–4287). Bovine embryos can be reconstructed with donor cells thawed immediately before NT, but it is not known if epigenetic changes arise during cell cryopreservation, and if NT efficiency is affected. The acetylated form of histone H3-lysine 9-lysine 14 (acH3K9/14) is associated with active chromatin configuration (Rice and Allis 2001 Curr. Opin. Cell Biol. 13, 263–273) and active transcription (Fuks 2005 Curr. Opin. Genet. Dev. 15, 490–495) and, thus, can be used as a marker to determine epigenetic changes in somatic cells. The purpose of our study was to evaluate histone acetylation levels of cultured and cryopreserved bovine fibroblasts. Cells were derived from skin of three adult cows and cultured in GMEM for 15 days. Fibroblasts from each of the three cell lines were analyzed at passage 1 (P1), 2 (P2), and 10 (P10). At each of the three passages, cells were cultured until reaching 100% confluence, followed by an additional 3 days in culture during which time acetylation levels were measured in fresh and frozen cells. For cryopreservation, cells at P1, P2, and P10 were disaggregated with accutase, resuspended in CryoStor™ (CS10; BioLife Solutions, Bothell, WA, USA), and cooled at 1.0°C min–1 to –80°C prior to storage in liquid nitrogen. Cells were fixed with ethanol for 12 h and incubated for 30 min with antibody directed against acetylated lysine 9 on histone 3 (H3K9). Then, cells were incubated with a fluorescein isothiocyanate (FITC) conjugated secondary antibody and DNA stain and evaluated by flow cytometry. Overall, histone acetylation levels in frozen cells (70%) were lower than levels in fresh cells (86%; P < 0.05), and all cell lines, whether fresh or frozen, showed lower acetylation levels at P1 (61%) than at P2 and P10 (88% and 85%, respectively; P < 0.001). No significant differences were observed between individual cell lines for fresh and frozen treatments. However, frozen cells from cell line 3 showed lower histone acetylation levels than fresh cells from cell line 3 and cell lines 1 and 2 at each passage. In summary, histone acetylation levels were lower in cryopreserved bovine fibroblasts and were higher in cell lines cultured for longer times. Table 1. Flow cytometrically detected acetylation levels of lysine 9 on histone 3 in cultured or cryopreserved bovine fibroblast cell lines passed for 1, 2, or 10 times

Reversal of motility loss in bongo antelope (Tragelaphus eurycerus isaaci) spermatozoa contaminated with hyposmotic urine during electroejaculation

Semen collected by a combination of ampullary (rectal) massage and electroejaculation of a bongo bull was incidentally contaminated with urine (1:3.7). At 1.5h post-collection, progressive motility was 0% but some spermatozoa had intermittently twitching tails. Subsequent dilution with media and processing improved the progressive motility (up to 50%) and intact membranes (up to 71%) of spermatozoa. After thawing, the respective values were 35 and 70%. The osmolarity and pH of the contaminated supernatant was 151 mOsm and 7.45, respectively. Initial progressive motility in a non-contaminated portion of semen collected during the same procedure was 80%, and, after thawing, 60 and 90%, of the spermatozoa showed progressive motility and intact membranes, respectively. In conclusion, urine-contaminated bongo spermatozoa can regain progressive motility after dilution with isosmotic solutions and survive cryopreservation.

Isolation, culture and characterisation of somatic cells derived from semen and milk of endangered sheep and eland antelope

Semen and milk are potential sources of somatic cells for genome banks. In the present study, we cultured and characterised cells from: (1) cooled sheep milk; (2) fresh, cooled and frozen–thawed semen from Gulf Coast native (GCN) sheep (Ovis aries); and (3) fresh eland (Taurotragus oryx) semen. Cells attached to the culture surface from fresh (29%), cooled (43%) and slow-frozen (1°C/min; 14%) ram semen, whereas no attachment occurred in the fast-frozen (10°C/min) group. Proliferation occurred in fresh (50%) and cooled (100%) groups, but no cells proliferated after passage 1 (P1). Eland semen yielded cell lines (100%) that were cryopreserved at P1. In samples from GCN and cross-bred milk, cell attachment (83% and 95%, respectively) and proliferation (60% and 37%, respectively) were observed. Immunocytochemical detection of cytokeratin indicated an epithelial origin of semen-derived cells, whereas milk yielded either fibroblasts, epithelial or a mixture of cell types. Deoxyribonucleic acid microsatellite analysis using cattle-derived markers confirmed that eland cells were from the semen donor. Eland epithelial cells were transferred into eland oocytes and 12 (71%), six (35%) and two (12%) embryos cleaved and developed to morulae or blastocyst stages, respectively. In conclusion, we have developed a technique for obtaining somatic cells from semen. We have also demonstrated that semen-derived cells can serve as karyoplast donors for nuclear transfer.

249 INTRACYTOPLASMIC SPERM INJECTION OF ELAND (TAUROTRAGUS ORYX) AND BONGO (TRAGELAPHUS EURYCERUS)ANTELOPE OOCYTES

Intracytoplasmic sperm injection (ICSI) is an assisted reproductive technique applicable in cases of limited male gamete availability. Moreover, it bypasses barriers of the oocyte, thus avoiding poorly understood species-specific capacitation events affecting sperm–egg interaction. In the present study, we evaluated the application of conventional and piezo drill-assisted ICSI and whether subsequent chemical activation is required for initiating embryonic development in eland (Taurotragus oryx) and bongo (Tragelaphus eurycerus) oocytes. Oocytes were collected using transvaginal ultrasound-guided follicular aspiration after gonadotropin-induced ovarian stimulation and incubated in modified TCM-199 medium (Gomez et al. 2000 Reprod. Fertil. Dev. 12, 423) containing 10% FBS. After 3 to 24 h, the cumulus cell layers were removed either by repeated mouth-pipetting and/or by using hyaluronidase. Oocytes with an extruded first polar body were used for ICSI and the other oocytes were returned to culture and evaluated every six hours Piezo drill-assisted (Kimura and Yanagimachi 1995 Biol. Reprod. 52, 709) or conventional (Gomez et al.) ICSI were done as described previously using glass pipettes with internal tip diameters of 9–10 µm. We used frozen–thawed or freshly collected spermatozoa that were kept in HEPES-buffered Tyrode's medium (Gomez et al.) for up to 24 h. Four to 6 h after ICSI, 3 activation treatments were examined: (1) none; (2) 7% ethanol, 5 min; or (3) calcium ionophore (5 µM, 5 min) followed by DMAP (2 mM, 4 h). Then we cultured oocytes in a humidified atmosphere of 5% O2, 5% CO2, and 90% N2 at 38.5°C in one of 3 media: SOF, α-MEM, or CR1aa containing essential and nonessential amino acids and FBS. Fifty-three of 70 (76%) eland oocytes survived after piezo-ICSI, and 13 of 16 (81%) survived after conventional ICSI. For bongo oocytes, 27 of 30 (90%) survived piezo-ICSI and all (n = 8) survived after conventional ICSI. Table 1 outlines cleavage data on Day 2. Generally, embryonic development was arrested at about 10 cells. In summary, eland and bongo oocytes can survive both conventional and piezo drill-assisted ICSI. Activation treatments do not appear to be a prerequisite for initiating cleavage after ICSI in eland and bongo antelope oocytes. Table 1.Cleavage of eland and bongo antelope oocytes after conventional or piezo-ICSI and three activation treatments

112 VIABILITY AND APOPTOSIS OF BOVINE FIBROBLASTS FROZEN IN A CONVENTIONAL ( - 20°C) OR LOW-TEMPERATURE ( - 80°C) FREEZER

Fibroblasts are commonly frozen in dimethyl sulfoxide (DMSO, 10% v/v) at a cooling rate of 1°C min−1 in cryo-containers placed in a low-temperature (−80°C) freezer (LTF) overnight before storage in liquid nitrogen (LN2). LTFs are not always available and cell viability may be altered by freezing at different cooling rates. Therefore, the purpose of the present study was to evaluate apoptosis and viability of bovine fibroblasts frozen at different cooling rates in a −80°C freezer or conventional −20°C freezer. Fibroblasts were generated from skin tissue collected from an adult female cow. Tissue was cut and cultured in DMEM for 7 to 10 days and passaged 2 or 3 times before being cryopreserved. Cells were frozen by one of 6 procedures; cells that were not frozen served as a control. To be frozen, cells were resuspended in DMEM + 10% FBS and 10% DMSO in 2-mL cryo-vials before being placed into freezing containers (Mr. Frosty, Nalgene). For groups 1 and 2, the container was placed in a −20°C freezer and cooled at ≈0.6°C min−1 to −7°C; ice formation was induced by seeding, after which cooling was continued at ≈0.6°C min−1 to −20°C. Vials in groups 1 and 2 were placed in LN2 after 1 h and 16 to 18 h, respectively. Group 3 and 4 vials were also cooled to −20°C at 0.6°C min, except that these samples were not seeded. After being held at −20°C for 16 to 18 h, group 3 vials were thawed; group 4 vials were stored in LN2. Vials in groups 5 and 6 were placed into a Mr. Frosty container and cooled at ≈1°C min−1 in a −80°C freezer. After being held at −80°C for 16 to 18 h, group 5 vials were thawed, and group 6 vials were placed into LN2. Group 1, 2, 3, and 4 vials were thawed in a 37°C water bath; group 5 and 6 vials were thawed in a 40°C water bath. Cell viabilities were quantified by using TB exclusion (TB) with microscopy. At least 20 000 cells from each group were thawed, and caspase 3, a key enzyme involved in apoptotic processes, was detected using a Caspase 3-FLICA apoptosis detection kit; propidium iodide-stained nuclei were assessed with cytometry (FCM) to determine viability (Table 1). Data were analyzed by ANOVA (P &lt; 0.05). Although there were viability differences among groups, freezer type, seeding, holding time, and LN2 had no significant impact, as assessed by TB or FCM; however, no LN2 significantly increased the percentage of viable cells displaying apoptosis. In summary, bovine fibroblasts were successfully frozen in a conventional (−20°C) freezer before storage in LN2. Table 1. Viability and apoptosis of bovine fibroblasts frozen at −20°C or −80°C

63 IMPROVEMENT OF SEMEN-DERIVED EPITHELIAL CELL PROLIFERATION BY FIBROBLAST CO-CULTURE

We previously isolated epithelial-like cells (ELC) from sheep (Ovis aries) and eland (Taurotragus oryx) semen (Nel-Themaat et al. 2004 Reprod. Fertil. Dev. 16, 152) and subsequently developed a system to separate ELC before plating (Nel-Themaat et al. 2005 Reprod. Fertil. Dev. 17, 314). Cells attached and proliferated in only 50% and 31% of the attempts, respectively. Therefore, the purposes of the present study were to improve ELC proliferation by co-culture with inactivated 3T3 mouse fibroblasts and to characterize the obtained cells. Semen fractions from two mature Gulf Coast Native rams (n = 20 ejaculates) and one common eland bull (n = 2 ejaculates) were plated on feeder layers (A), on collagen with feeder cell inserts (B), or on collagen alone (C). For B and C, cell attachment and division were assessed; proliferation and passage 1 (P1) confluence were evaluated for A, B, and C. No difference in attachment rates between B (80%) and C (70%) were found for ovine cells, but (P < 0.05) cells divided more times in B (80%) than in C (35%). All colonies in A (60%) and B (70%) reached P1 confluence and no difference was detected between A and B, but less proliferation (10%) and P1 confluence (5%) were observed in C. Therefore, contact between epithelial cells and feeders was not necessary for growth stimulation by the feeder cells. No difference among A, B, and C was detected for eland ELC proliferation (100%), but no P1 confluence was observed in C. Ram cells were subsequently characterized by immunohistochemical detection of keratin and vimentin, as well as morphology. The 3T3 cells cross-reacted with keratin, and characterization was thus performed mainly on morphology and vimentin expression. Distribution of vimentin microfilaments differed between different epithelial morphologies and fibroblasts. Expression in epithelial cells was faint and patchy in confluent colonies and located around cytoplasmic extremities in semi-confluent colonies. In 3T3 cells, expression was very prominent throughout the cytoplasm and around the nucleus. For treatments A and B, 63 and 57%, respectively, were characterized as only epithelial cells; 25 and 36%, respectively, appeared to contain a mixture of epithelial and fibroblast cells; and 13 and 7%, respectively, contained only fibroblast cells. Only one sample was evaluated from treatment C and only keratin was detected in the epithelial-like colony. We conclude that culture of semen-derived ELC is markedly improved by 3T3 fibroblast co-culture. Further research on conditioned media may simplify the system and reduce chances of 3T3 cell contamination.

115 SPERM CRYOPRESERVATION IN TRAGELAPHINE ANTELOPES

As an integral aspect of our program to develop assisted reproductive technologies in tragelaphine antelopes, we have been evaluating the effects of various extenders on cryosurvival of spermatozoa. Semen was collected by electroejaculation (EEJ) from an eland (Taurotragus oryx, n = 14 EEJs) and a bongo (Tragelaphus euryceros, n = 7 EEJs) male during sedation and standing restraint in a hydraulic chute. Epididymal spermatozoa were collected from the proximal vas deferens, and distal epididymides recovered from four common eland bulls after elective castration at the Hattiesburg Zoo, Mississippi (age = 46 months) and the San Diego Wild Animal Park, California (ages = 18, 20, and 23 months). Testes from a bongo (age = 6.5 yr) and a greater kudu bull (Tragelaphus strepsiceros, age = 7.5 yr) at the Audubon Nature Institute were recovered and processed immediately postmortem. Kudu, bongo, and the Hattiesburg eland testes were transported at ambient temperature whereas the testes from San Diego elands were shipped overnight in a cold-pack container. Sperm processing was done at room temperature (RT = 23°C) in HEPES-buffered Tyrode's solution. Four extenders containing 7% glycerol were evaluated: Biladyl®, TEST Yolk buffer (TYB), Beltsville extender (BF5F), and skim milk. For freezing, sperm samples were initially extended and gradually cooled to 4°C before sequential addition of extender containing glycerol at 4°C; the procedure was then modified by addition of the glycerol fraction at RT before the sample was cooled to 4°C. Spermatozoa were vapor-frozen in 0.5 mL straws placed 5 cm above liquid nitrogen before storage at −196°C. Straws were thawed in a water bath (38°C, 30 s) to evaluate cryosurvival. All eland and bongo electroejaculation procedures produced spermatozoa, although sperm quality varied. Ejaculate volume averaged 5.4 ± 1.2 mL and 3.7 ± 1.1 mL in the bongo and the eland, respectively. Sperm motility at collection, after cooling, and after freezing in the different extenders is presented in Table 1. No immediate decline in sperm motility was observed after adding glycerol to samples, whether at 23°C or 4°C. Bongo spermatozoa lost more motility during freezing than during cooling (15.0 ± 4.4 vs. 5.8 ± 2.0%; P = 0.006); whereas, in eland, motility loss during cooling and freezing was similar (25.3 ± 16.2 vs. 21.1 ± 7.7; P = 0.44). The present results indicate that cooling and freezing tolerance of spermatozoa in tragelaphine antelopes is influenced by species, extender type, and temperature at which a cryoprotectant is added. Table 1. Cryosurvival of ejaculated or epididymal spermatozoa of three antelope species in different extenders

BEHAVIORAL TRAINING AND HYDRAULIC CHUTE RESTRAINT ENABLES HANDLING OF ELAND ANTELOPE (TAUROTRAGUS ORYX) WITHOUT GENERAL ANESTHESIA

Difficulties and risks associated with restraining large nondomestic ungulates are limiting factors toward developing and applying assisted reproductive technologies, such as artificial insemination and embryo transfer. In this study on 10 female eland (Taurotragus oryx), we evaluated the use of behavioral training and handling handling in a hydraulic chute to perform transvaginal ultrasound-guided oocyte retrieval and other clinical procedures. Nine females were conditioned to associate specific sound cues with food treats. The interval from the audio cue until acceptance of handheld treats varied among females (1.8-58.3 min). Animals also differed in their response to training for voluntary entry into the chute. Handling eland for oocyte retrieval in the hydraulic chute required xylazine sedation. During sedation and handling, eland undergoing oocyte retrieval procedures had higher blood glucose levels (14.4 +/- 3.1) than females handled similarly but without oocyte retrieval (9.3 +/- 2.7 mmol/L). Plasma osmotic pressure, hematocrit, and creatine phosphokinase activity were similar between these two groups. Females that were more difficult to train had higher blood glucose levels than the more cooperative animals. Cooperative females had fewer vertical stripes on their sides. More than 40 procedures were conducted without complications or mortality. The combination of behavioral conditioning-training and restraint of sedated eland in a hydraulic chute was a reliable and repeatable method for performing minimally invasive assisted reproductive techniques.

328 SOMATIC CELL ISOLATION FROM SEMEN BY PERCOLL GRADIENTS

We previously isolated epithelial-like cells (ELC) from sheep (Ovis aries) and eland (Taurotragus oryx) ejaculates (Nel-Themaat et al. 2004 Reprod. Fertil. Dev. 16, 152). Success rates were low, and the presence of live sperm during initial culture may have altered medium properties, physically prevented contact between cells and the substrate, and/or damaged somatic cell membranes. Using the complete semen sample requires the sacrifice of valuable live spermatozoa without the certainty of obtaining a somatic cell population. Therefore, the purpose of the present study was to develop a method for isolating somatic cells from semen before culture. Separation by discontinuous Percoll gradient centrifugation was performed. Ejaculates obtained by electro-ejaculation from two Louisiana Native rams and rectal massage of one eland bull were washed, layered on columns of 2.5 mL each of 20% (P-20), 50% (P-50), and 90% (P-90) Percoll in 15-mL conical tubes, and centrifuged for 20 min at 400g. Bands were obtained at the three interfaces, as well as a pellet in the P-90 fraction. Each Percoll layer plus the interface band immediately below it was collected by aspiration. Cells from each fraction were re-suspended in serum-supplemented Minimum Essential Medium Alpha containing 500 IU/mL of penicillin, 0.5 mg/mL of streptomycin and 250 g/mL of gentamycin, and were plated on collagen-1 coated dishes. Trypan blue staining was used to determine cell viability in each fraction. After 24 h, dishes were washed and the culture continued until cells attached and proliferated. For both species, the surface fraction yielded primarily dead ELC that were morphologically flat and angular in shape. In the P-20 band, more viable cells were isolated compared with other fractions, although dead cells were also present. In the P-50 and P-90 fractions, few ELC were observed compared with the surface and P-20 fractions. A negligible number of sperm was observed in the surface and P-20 fractions. In contrast, mostly dead sperm were found at the P-50 and P-90 interface band, whereas live spermatozoa were detected in the P-90 pellet. Epithelial-like cells isolated from semen of both species attached (A, initial 24 h of culture), divided (D, within 3 days after plating), and proliferated (P, after 1 week of culture) (see Table). Ram ELC derived from the surface and from the P-20 and P-50 layers attached, but proliferation was detected only with cells collected in the P-20 fraction. In contrast, eland cells collected from the surface and P-20 layers readily attached and proliferated. In summary, a technique has been developed for the isolation of somatic cells from semen using a three-layer Percoll gradient. This method also allows the isolation of motile spermatozoa, hich are available for further use.

162INSULIN IMPROVES FREQUENCY OF CLEAVAGE AND IN VITRO DEVELOPMENT OF BOVINE EMBRYOS IN DEFINED MEDIUM

Pre-elongation stage bovine embryos contain insulin receptor, ligands and receptors of IGF-I and IGF-II, and possibly EGF ligand. Cumulus cells and blastocysts also express EGF receptor; however, insulin is not produced (Watson AJ et al. 1992 Mol. Reprod. Dev. 31, 87–95; Tetens F. et al. 2000 Anat. Embryol. 201, 349–55; Yaseen MA et al. 2001 Reproduction 122, 601-10). Reported effects of external growth factors during bovine IVC are conflicting. The present study evaluated effects of EGF and insulin on the development of in vitro-produced embryos in a chemically defined IVC medium. IVM medium was TCM199 plus fetal bovine serum, LH and estradiol. IVF was done in Tyrodes solution containing BSA, lactate, pyruvate, heparin, penicillamine-hypotaurine-epinephrine and nonessential amino acids. At 18h post-insemination, ova were vortexed, washed and placed in IVC treatments. Modified KSOM (Yang BK et al. 1995 J. Reprod. Dev. 41, 213–18) with 1X MEM nonessential and 1X BME amino acids was the base IVC medium. Incubations were done at 39°C in a humidified atmosphere of 5% CO2 in air (IVM, IVF) or 5% CO2, 10% O2 and 85% N2 (IVC). Effects of three EGF (0, 50, 100ngmL−1; Experiment 1) or five insulin (0, 5, 10, 15, 20μgmL−1; Experiment 2) doses were tested, in five replicates, by supplementation during the entire IVC period (up to Day 9; Day 0=day of insemination). Embryos were placed in fresh medium on Day 4 post-insemination. Data were analyzed using one-way ANOVA and Tukey’s test. In Experiment 1 (n=646 oocytes), EGF treatment did not affect percentages of Day 2 cleavage (83±3, 82±3, and 81±2%, respectively; mean±SEM.) and Day 9 blastocysts (34±4, 33±4 and 33±5%, respectively) or cell number per blastocyst after Hoechst staining (95±5, 88±4 and 89±5, respectively). In Experiment 2 (n=687 oocytes), insulin improved the frequency of cleavage and percentage of expanding, hatching and total blastocysts. It also increased blastocyst cell number (see Table 1). Lack of effect of EGF on bovine IVC is in contrast to its widely reported beneficial effects in mice. In many bovine IVC studies, the beneficial effects of external insulin were seen at or after the morula stage. The present study demonstrates that insulin can influence embryonic development as early as the initial cleavage stage and before embryonic genome activation. Reseach was funded in part by J. Bennett Johnston Science Foundation. Table 1 Effects of insulin (μgmL−1) on development to &gt;2-cell (Day 2), expanded, hatched and total blastocysts (Day 9: %±SEM) and on blastocyst cell number (Day 9: mean±SEM)

140A STUDY ON HINNY PRODUCTION FROM LOCAL JENNIES (EQUUS ASINUS) AND STALLIONS (E. CABALLUS) IN ETHIOPIA: NORMAL OFFSPRING PRODUCED

Domestic equids, consisting of 5 million donkeys, 1 million horses and 0.6 million mules, play important roles in Ethiopia’s economy by providing services in transportation and traction sectors. In spite of the large equine population and the common use of mules (jack×mare), the opposite hybrid, hinny (stallion×jenny) is uncommon. Compared to using mules or either parent, hinnies could provide certain economic and environmental advantages. Considering the large female donkey population, it may be easier and more affordable to produce hinnies than mules. Moreover, hinnies are better than donkeys in draft performance. Thus, using hinnies could help in reducing the large donkey population and hence their negative environmental effect. However, there is no recorded attempt of hinny production in Ethiopia. Although data from controlled experiments are limited, interspecies breeding to produce hinnies is less successful than attempts to produce mules mainly because hinnies are thought to be less fertile. In the present study, adult and cycling Abyssinian jennies were divided into two groups (n=10 each) for natural breeding with three jacks (Jack group) or four stallions (Stallion group). During a period of two years, data on intraspecies and interspecies courtship behavior, mating activities, conception and foaling were recorded. Data were collected mainly by visual observation. Pregnancy was also diagnosed by palpation per rectum at 60 to 90 days after service. Mating was conducted during natural or PGF2α-induced estrus. Data on the number of services per conception, number of pregnancies and foaling were compared using chi-square or Fisher’s test. Jennies in estrus showed overt sexual interest in jacks, stallions and even female herdmates. Two stallions showed sexual interest in jennies; however, only one mated successfully and hence jennies in heat were exposed to this male. In the Jack group, 9 of the 10 jennies conceived (with 27 cycles bred , or 3 cycles/pregnancy). One pregnant jenny died of unrelated causes. Of the remaining 8 pregnant jennies, 3 aborted and 5 delivered live foals. In the stallion group, 3 of the 10 jennies conceived (with 47 cycles bred, or 15.7 cycles/pregnancy). Two of the three females aborted and one delivered a live female foal. The pregnancy rates between the two treatments (90% v. 30%) were significantly different (P=0.02); however, treatment did not affect (P&gt;0.05) foaling rates (63 % v. 33%) or abortion rates (38% v. 67%). Abortion occurred at 192 to 254 days (Jack group) and 147 and 159 days (Stallion group) of gestation. Gestation lengths of 370.2±4.5 v. 330 day and foal body weight of 13.3±1.0 v. 16kg were recorded in the Jack and Stallion groups, respectively. Foaling did not require assistance in either group. We have demonstrated the possibility of hinny production using local jennies and stallions. The main limitations to hinny production were poor sexual desire of stallions towards jennies and also low conception rates after interspecies mating. The latter also cast doubts on the potential of alternative approaches (e.g. artificial insemination) to circumvent the behavioral barrier to interspecies breeding. We would like to thank RPSUD for funding this project and Dr. Azage Tegegne for overall assistance.

Xenogenous fertilization of equine oocytes following recovery from slaughterhouse ovaries and in vitro maturation

The in vitro production (IVP) of equine embryos using currently available protocols has met limited success; therefore investigations into alternative approaches to IVP are justified. The objective of this study was to evaluate the feasibility of xenogenous fertilization and early embryo development of in vitro matured (IVM) equine oocytes. Follicular aspirations followed by slicing of ovarian tissue were performed on 202 equine ovaries obtained from an abattoir. A total of 667 oocytes (3.3 per ovary) were recovered from 1023 follicles (recovery rate, 65%). Oocytes underwent IVM for 41 +/- 2 h (mean +/- S.D.), before being subjected to xenogenous gamete intrafallopian transfer (XGIFT). An average of 13 +/- 0.8 oocytes and 40x10(3) spermatozoa per oocyte were transferred into 20 oviducts of ewes. Fourteen percent of transferred oocytes (36/259) were recovered between 2 and 7 days post-XGIFT and 36% of those recovered displayed embryonic development ranging from the 2-cell to the blastocyst stage. Fertilization following XGIFT was also demonstrated by the detection of zinc finger protein Y (ZFY) loci. Ligation of the uterotubal junction (UTJ), ovarian structures, or the duration of oviductal incubation did not significantly affect the frequency of embryonic development or recovery of oocytes/embryos after XGIFT. In conclusion, equine embryos can be produced in a smaller non-equine species that is easier for handling.

Development of in-vitro-derived bovine embryos in protein-free media: effects of amino acids, glucose, pyruvate, lactate, phosphate and osmotic pressure

In experiment 1, the effects of a group of either 20 (i.e. glutamine + essential + non-essential) or 11 (i.e. hamster embryo culture medium (HECM)-6) amino acids were evaluated in modified potassium simplex optimised medium (mKSOM) or basic medium (BM)-3. In experiment 2, the effects of glucose, pyruvate, lactate, phosphate or all four substrates were evaluated in low- or high-osmotic pressure BM-3 (255 and 275 mOsmol respectively) containing 20 amino acids (BM-3-20aa). In experiment 1, mKSOM containing 20 amino acids (mKSOM-20aa) supported the highest frequency of total, expanded (Days 7, 8 and 9) and hatched blastocysts. In experiment 2, supplement type affected the frequency of development to at least the morula stage (Day 7), expanded (Day 8), hatched (Day 9) or total blastocysts and cell number per blastocyst. Osmotic pressure affected the frequency of expanded blastocysts (Day 7) and blastocyst cell number. Regardless of the osmotic pressure, BM-3-20aa containing glucose (0.2 mm) supported the highest frequency of blastocyst development. The interaction between supplement type and osmotic pressure was not significant; however, treatment mean differences were more marked in high- than in low-osmotic pressure medium. In conclusion, the beneficial effects of amino acids on in vitro embryo development are influenced by the base medium. Moreover, glucose-containing media supported a higher frequency of embryonic development than pyruvate- and/or phosphate-supplemented media, indicating that glucose plays more important roles in non-energy generating pathways.