The Camel Reproduction Centre, Dubai, United Arab Emirates. email@example.com
The camelid family comprises the Old World camelids (or dromedary and Bactrian camels) and the New World camelids (namely the llamas, alpacas, guanacos and vicunas). Although the species within each group can hybridize among themselves to produce fertile offspring, it is only recently that a hybrid between New and Old World camelids has been reported. To create this hybrid, semen was collected from male camels by artificial vagina (AV) and inseminated into female guanacos (n = 9) and llamas (n = 3) at the appropriate stage of their follicular wave cycle. Similarly, guanaco and llama semen was collected, also by AV, and inseminated into female camels (n = 42). Although several conceptions occurred, only one hybrid (camel sire x guanaco dam) continued to term and was born alive after 328 days of gestation, and another is pregnant at the time of writing (camel sire x llama dam). Further studies are presently being carried out using extraspecific embryo transfer to try and improve the success rate of live offspring being born. Female guanacos (n = 4) are treated with hormones to stimulate their ovaries to produce several follicles before being inseminated with camel semen. Of the 12 camel recipients that have to date received hybrid embryos (camel sire x guanaco dam), 10 conceived, but 9 of these subsequently aborted between 30 and 365 days and only one recipient was still pregnant at the time of writing.
Department of Anthropology, New York University, Rufus D. Smith Hall, 25 Waverly Place, New York, New York 10003, USA. firstname.lastname@example.org
Interspecies embryo transfer in camelids: the birth of the first Bactrian camel calves (Camelus bactrianus) from dromedary camels (Camelus dromedarius).
Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran 14155-6453, Iran. email@example.com
Interspecies embryo transfer is a possible approach that can be used to conserve endangered species. It could provide a useful technique to preserve the Iranian and wild Bactrian camels, both of which are threatened with extinction. In the present study, one Bactrian camel was superovulated using decreasing doses of FSH (60, 40, 30, 30, 20, 20 mg, b.i.d.; Folltropin-V; Bioniche, London, ON, Canada) for 6 days, followed by a single injection of FSH (20 mg, i.m.) on Day 7. Daily ovarian ultrasonography was performed until most of the growing follicles had reached a mature size of 13-17 mm, at which time the camel was mated twice, 24 h apart, with a fertile male Bactrian camel. At the time of first mating, female camels were given 20 microg, i.v., buserelin (Receptal; Intervet, Boxmeer, The Netherlands). One day after the donor camel had been mated, the dromedary recipients (n = 8) were injected with 25 mg, i.v., porcine LH (Lutropin-V; Bioniche) to induce ovulation. Embryos were recovered on Day 8.5 after the first mating and transferred non-surgically into recipients on Day 7.5 after LH injection. Pregnancy was diagnosed 25 days after embryo transfer. Healthy Bactrian camel calves (n = 4) were born without any particular complications at the time of parturition (e.g. dystocia and neonatal diseases). The present study is the first report of the birth of Bactrian camel calves from dromedary camels, as well as the first report of interspecies embryo transfer in old world camelids.
Department of Anthropology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA.
Recent developments in evolutionary biology have conflicting implications for our understanding of the developmental bases of microevolutionary processes. On the one hand, Darwinian theory predicts that evolution occurs mostly gradually and incrementally through selection on small-scale, heritable changes in phenotype within populations. On the other hand, many discoveries in evolutionary developmental biology--quite a few based on comparisons of distantly related model organisms--suggest that relatively simple transformations of developmental pathways can lead to dramatic, rapid change in phenotype. Here I review the history of and bases for gradualist versus punctuationalist views from a developmental perspective, and propose a framework with which to reconcile them. Notably, while tinkering with developmental pathways can underlie large-scale transformations in body plan, the phenotypic effect of these changes is often modulated by the complexity of the genetic and epigenetic contexts in which they develop. Thus the phenotypic effects of mutations of potentially large effect can manifest themselves rapidly, but they are more likely to emerge more incrementally over evolutionary time via transitional forms as natural selection within populations acts on their expression. To test these hypotheses, and to better understand how developmental shifts underlie microevolutionary change, future research needs to be directed at understanding how complex developmental networks, both genetic and epigenetic, structure the phenotypic effects of particular mutations within populations of organisms.
Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, University at Al-Qassim, P.O. Box 1482, Buraydah, Saudi Arabia. firstname.lastname@example.org
Research into infertility in the dromedary bull, as reported during the last two decades, is reviewed with emphasis on causes and effects. Reproductive activity of such animals is naturally limited by a breeding season, though with enough encouragement some may mate with oestrous females out of season but a full fertilization potential can in no way be expected. It is essential that any female presented to a bull is capable of reproducing. The presentation of a subfertile or infertile female due to infection or physiological abnormality will adversely affect the female's ability to conceive and, therefore, the apparent fertility rates of the bull she was put to. The average number of successful services a bull could be expected to perform is two per day. Dromedary bulls with large testes have larger sperm outputs and can cope with more than two females per day providing that they are given adequate periods of rest, 1-2 days every 10 days or so, in conjunction with appropriate nutrition throughout the season. Anabolic steroids or testosterone therapies, which are sometimes used in an attempt to improve male characteristics and bull libido, are not recommended for dromedary bulls in breeding work. Such steroids result in a decrease in testicular size and weight with fewer sperm per gram of testicular tissue being found and the sperm produced also have lower motility rates. Pain associated with the act of mating a she-camel, due to injuries or inflammation in the scrotum, testes, prepuce and sheath, can cause a permanent reduction in bull libido. Camel bulls achieving pregnancy rates more than 60% have had consistently higher spermatozoal concentrations and kinematic variables derived by the computerized cell motion analyzer (CMA) system. As far as physical capabilities are concerned, 3-year-old dromedary bulls, which have reached puberty, have been shown to be perfectly capable of fertilizing a female, but they have a limited sperm production to perform consistently throughout the season in a large herd. By 4.5-5.0 years of age, they are capable of producing adequate numbers of sperm to mate as many as females as an adult bull but fertilizing capacity is not attained until 6 years of age on average. Hyperoestrogenaemia, associated with autoimmune thyroiditis and trypanosomiasis, suppresses the secretion of testicular testosterone and augments the release of testicular histamine, which appears mandatory for quantitative reduction/loss of advanced spermatogenic cells in infertile dromedary bulls.
Changes in cumulus-oocyte complexes of pregnant and non-pregnant camels (Camelus dromedarius) during maturation in vitro.
Research Institute for the Biology of Farm Animals, 18196 Dummerstorf, Germany. email@example.com
The aim of the present study was to examine the cumulus morphology and the oocyte chromatin quality of camel cumulus-oocyte complexes (COCs) at the time of recovery, and to monitor changes in oocyte chromatin configuration and apoptosis in cumulus cells from camel COCs during in vitro maturation (IVM)(0, 12, 24, 32, 36, 42, and 48 p.IVM) depending on pregnancy of donors. A total of 1023 COCs were isolated from sliced ovaries after slaughtering of 47 pregnant and 43 non-pregnant camels in an abattoir. The mean number of COCs per donor was 10.3 in pregnant and 12.5 in non-pregnant donors. The cumulus morphology of COCs was independent of the type of donor and was divided in COCs with compact (26.9 and 28%), dispersed (39.3 and 46%), corona radiata cumulus investment (27.9 and 21.7%) and without cumulus (6 and 4.2%), respectively for pregnant and non-pregnant donors. The highest proportion of COCs exhibited dispersed cumulus (P<0.05). Oocytes with meiotic stages of diplotene >50% were found only in compact (55 and 56.5%) and in dispersed COCs (58.4 and 60%), respectively for pregnant and non-pregnant donors. During IVM (0-48h) the first significant onset of specific meiotic stages were different in oocytes from pregnant donors: metaphase 1 (24-32h), metaphase 2 (36-42h), versus oocytes from non-pregnant donors: metaphase 1 (24h), metaphase 2 (32-48h)(P<0.05). The level of apoptotic cells in cumuli of matured COCs increased during IVM and was higher in matured COCs from non-pregnant donors for each time point during IVM (P<0.01). Camel oocytes meiosis during IVM is accompanied by a drastic increase of apoptosis in the surrounding cumulus cells 0-32 and 0-24h during IVM, respectively for pregnant and non-pregnant donors. The oocytes of pregnant camels require 36h of maturation to reach levels of >50% metaphase 2 stage in comparison to oocytes from non-pregnant donors where 32h are sufficient. The earlier onset of apoptosis in the COCs derived from non-pregnant donors possibly determines the faster progression of the oocytes through the final stages of meiosis.
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Camel Reproduction Centre, Dubai, United Arab Emirates.
Thirty female dromedary camels were inseminated on a total of 50 occasions with 2-4 ml of fresh guanaco semen diluted with an equal volume of commercially available camel semen extender. Similarly, nine female guanacos were inseminated on 34 occasions with 4-6 ml of fresh, diluted camel semen. Only two of the dromedary females conceived; one aborted a female foetus on day 260 of gestation and the other gave birth to a stillborn female calf on day 365. Six conceptions occurred in the female guanacos. Two of these conceptuses, diagnosed by ultrasound, were resorbed between days 25 and 40 of gestation, one female foetus was aborted on day 291, another female foetus was aborted on day 302, and one female calf was stillborn on day 365 of gestation. The sixth foetus, a male, was born prematurely but alive after a 328-day gestation. It had a phenotypic appearance intermediate between that of a camel and a guanaco and its hybrid parentage was confirmed by the DNA fingerprinting of eight llama microsatellites. To our knowledge, this is the first viable hybrid ever to be produced between Old World and New World camelids, which have been reproductively isolated from one another for at least 11 million years. The preponderance of female hybrids is in accordance with Haldane's law. Histological examination of their ovaries revealed a failure of meiosis, with only an occasional abnormal oocyte surrounded by follicle cells. Although the diploid chromosone number of camels and guanacos is the same (2n = 74), sufficient genetic change has taken place to make the pairing of homologous chromosomes no longer possible.
Camel Reproduction Laboratory, Nakhlee, Dubai, UAE.
Peripheral serum samples were collected from 8 pregnant dromedary camels and hormone secretion patterns were examined at specific time intervals. Mean serum progesterone concentrations began to rise 3-4 days after ovulation and remained reasonably constant at 3-5 ng mL-1 for the first 90-100 days of gestation. Concentrations then showed a definite fall, but thereafter remained constant again at 2-4 ng mL-1 throughout the rest of pregnancy. In contrast, serum oestrogen concentrations showed pronounced fluctuations during the first 100 days of gestation. Mean oestradiol-17 beta concentrations increased at around Day 50 to about 100 pg mL-1 and then remained relatively constant from Day 90 to Day 300. Mean oestrone sulfate concentrations, however, showed two definite peaks in early gestation, each reaching about 10 ng mL-1, with the first peak occurring around Day 25 and the second peak around Day 75. Oestrogen production then remained fairly constant until around Day 300, after which concentrations of both oestrone sulfate and free oestradiol-17 beta rose steeply over the next 80 days to reach mean peak values of 46 ng ML-1 and 518.7 pg mL-1, respectively, at the time of parturition. Concentrations of 13,14 dihydro-15-keto prostaglandin F2 alpha (PGFM) remained low and reasonably steady at 100-200 pg mL-1 during the first 320 days of pregnancy; thereafter, PGFM concentrations rose steeply over the next 50 days, before an explosive further increase to a peak of 1900 +/- 141 pg mL-1 mean +/- sem on the day of calving. These results suggest that, as in the cow, a major change in steroid synthetic capability and/or enzyme content of the placenta may occur at around 80%(Day 300) of gestation in the pregnant camel.
The ovarian follicular wave pattern and induction of ovulation in the mated and non-mated one-humped camel (Camelus dromedarius).
Camel Reproduction Laboratory, Dubai, UAE.
Ovarian follicular wave patterns were studied ultrasonographically in three groups of dromedary. Group 1 camels (n = 20) were teased daily with a vasectomized male but mating was prevented; group 2 camels (n = 8) ran freely with a vasectomized male camel for 10 h each day and group 3 camels (n = 8) were kept completely separate from any males. In a second experiment (n = 63), when the diameter of the dominant follicle reached 0.5-0.9 cm, 1.0-1.9 cm, 2.0-2.9 cm or > 3 cm, the camel was given one of three treatments to induce ovulation:(i) natural mating;(ii) 20 micrograms of the GnRH analogue, buserelin; or (iii) 3000 iu hCG. The ovaries were re-scanned regularly to monitor ovulation, and daily blood samples were assayed for progesterone and oestradiol concentrations. The follicular cycle was divisible into a growth phase (10.5 +/- 0.5 days), a mature phase (7.6 +/- 0.8 days) and a regression phase (11.9 +/- 0.8 days). The dominant follicle reached a mean +/- SEM maximum diameter of 2.0 +/- 0.1 cm (range 1.5-2.5 cm) in 34 cycles (52%) before it began to regress. In the other 32 cycles (48%), however, the dominant follicle continued to grow to 4.2 +/- 0.2 cm (range 4.0-6.0 cm) before regression commenced. Group 2 camels were mated when their follicles reached 1.3 +/- 0.1 cm in diameter and the mean interval between successive matings was 13.8 +/- 1.0 days. Mean +/- SEM serum concentrations of oestradiol reached peak values at 39.0 +/- 1.8 pg ml-1, when the dominant follicle measured 1.7 +/- 0.1 cm and, after ovulation, mean serum concentrations of progesterone reached peak values at 2.6 +/- 0.3 ng ml-1 on day 8, before decreasing to < 1 ng ml-1 by day 10 or 11. When the dominant follicle measured 0.5-0.9 cm in diameter, 70%, 60% and 60% of them ovulated in response to mating, or treatment with buserelin or hCG, respectively. These ovulation rates increased to 85%(mating), 81%(buserelin) and 67%(hCG) when the follicle measured 1-1.9 cm, but they decreased again to 12.5%(mating), 29%(buserelin) and 13%(hCG) when the diameter had increased to 2.0-2.9 cm at the time of treatment. No follicles measuring > 3.0 cm ovulated in response to any of the treatments. These results indicated that the optimum time to mate or attempt to induce ovulation in the female dromedary is when the growing follicle measures 0.9-1.9 cm in diameter.
The ovarian follicular wave pattern in the mated and non-mated dromedary camel (Camelus dromedarius).
Camel Reproduction Laboratory, Nakhlee, Dubai, UAE, UK.
Experimental jetlag disrupts circadian clock genes but improves performance in racehorses after light-dependent rapid resetting of neuroendocrine systems and the rest-activity cycle.
D J Tortonese, D F Preedy, S A Hesketh, H N Webb, E S Wilkinson, W R Allen, C J Fuller, J Townsend, R V Short
Department of Anatomy, University of Bristol, Bristol, UK. firstname.lastname@example.org
Abrupt alterations in the 24-h light : dark cycle, such as those resulting from transmeridian air travel, disrupt circadian biological rhythms in humans with detrimental consequences on cognitive and physical performance. In the present study, a jetlag-simulated phase shift in photoperiod temporally impaired circadian peaks of peripheral clock gene expression in racehorses but acutely enhanced athletic performance without causing stress. Indices of aerobic and anaerobic capacities were significantly increased by a phase-advance, enabling prolonged physical activity before fatigue occurred. This was accompanied by rapid re-entrainment of the molecular clockwork and the circadian pattern of melatonin, with no disturbance of the adrenal cortical axis, but a timely rise in prolactin, which is a hormone known to target organs critical for physical performance. Subsequent studies showed that, unlike the circadian pattern of melatonin, and in contrast to other species, the daily rhythm of locomotor activity was completely eliminated under constant darkness, but it was restored immediately upon the reintroduction of a light : dark cycle. Resetting of the rhythm of locomotion was remarkably fast, revealing a rapid mechanism of adaptation and a species dependency on light exposure for the expression of daily diurnal activity. These results show that horses are exquisitely sensitive to sudden changes in photoperiod and that, unlike humans, can benefit from them; this appears to arise from powerful effects of light underlying a fast and advantageous process of adjustment to the phase shift.
Camel Reproduction Centre, Dubai, UAE. email@example.com
Artificial insemination (AI) is one of the most widely used reproductive technologies, and there is considerably interest in commercializing this technology in camels. Storage of semen extender frozen (at -20 °C) is of considerable interest to scientists working with camels, as transportation of diluents at refrigeration temperature is not always possible given the hot, arid and remote conditions that dromedary camels exist in. Therefore, this study was conducted to compare the fertility of fresh camel semen, after dilution in fresh or frozen-thawed green buffer (GB), after AI into single and multiple ovulating female camels. No differences were observed in any sperm characteristics (motility, membrane integrity, acrosome integrity or morphology) when semen was diluted in fresh or frozen-thawed GB (p>0.05). Sperm motility was increased by dilution (fresh: 70.7 ± 4.9% and frozen: 68.8 ± 3.1%) compared with the motility of sperm in neat semen (35 ± 2.85%; p<0.05), and sperm motility changed from oscillatory to forward progressive after dilution. Pregnancy rates were higher (p<0.05) for single ovulating camels inseminated with semen diluted in fresh (72.7%) compared with frozen-thawed GB (27.3%), and fertilization rates were also higher (p<0.05) for multiple ovulating camels inseminated with semen diluted in fresh (83.3%) compared with frozen-thawed GB (11.1%). These results clearly demonstrate the detrimental effect of freezing and thawing semen diluent on the fertility of fresh camel semen. However, further studies are required to elucidate the mechanism responsible for this reduction in fertility. Moreover, these results demonstrate that the fertility of fresh camel semen diluted in fresh GB is high enough to be considered commercially viable.
Embryo transfer in the dromedary camel (Camelus dromedarius) using non-ovulated and ovulated, asynchronous progesterone-treated recipients.
Camel Reproduction Centre, PO Box 79914, Dubai, United Arab Emirates. firstname.lastname@example.org
The aim of the present study was to investigate the use of exogenous progesterone and equine chorionic gonadotrophin (eCG) in non-ovulated and ovulated, asynchronous dromedary camel recipients being prepared for an embryo transfer programme. The uteri of 12 mated donor camels were flushed non-surgically 7 days after ovulation and 42 embryos were recovered. In Experiment 1, 16 embryos were transferred non-surgically to recipients on Day 3 or 4 after ovulation (ov+3 and ov+4, respectively). Each recipient received a daily dose of 75 mg, i.m., progesterone-in-oil from 2 days before embryo transfer until 6 days after ovulation. Thereafter, the progesterone dose was reduced to 50 mg on Day 7 and finally to 25 mg day(-1) on Days 8 and 9. Nine of 16 recipients (56%; ov+3, n=4; ov+4, n=5) became pregnant compared with none of eight non-progesterone treated controls, into which embryos were transferred on Day 4 after ovulation. In Experiment 2, 18 non-ovulated recipients received 75 mg, i.m., progesterone-in-oil daily from 3 days before until 12 days after non-surgical transfer of a Day 7 blastocyst, at which time pregnancy was diagnosed by ultrasonography. All pregnant recipients continued to receive 75 mg progesterone-in-oil daily for a further 6 days, when each camel received 2000 IU, i.m., eCG. Progesterone treatment was then reduced to 50 mg day(-1) and, when a follicle(s) ≥1.3 cm in diameter were present in the ovaries, each animal received 20 μg buserelin to induce ovulation. Once the corpora lutea had developed, progesterone treatment was reduced to 25 mg day(-1) for a final 3 days. Fourteen of 18 recipients (78%) became pregnant and seven of these (50%) remained pregnant after eCG treatment. Of the seven pregnancies that were lost, two were lost before eCG treatment, two did not respond to eCG treatment and three responded to eCG treatment and ovulated, but lost their pregnancies 6-8 days after the last progesterone injection.
The Camel Reproduction Centre, PO Box 79914, Dubai, United Arab Emirates. email@example.com
This study was designed to compare the efficacy of various treatments intended to synchronise follicular wave cycles in dromedary camels by removing the existing follicle of unknown size and replacing it with a follicle capable of ovulating at a known time. Camels were randomly assigned to one of five groups and treated with either (1) 5mg oestradiol benzoate (i.m.) and 100mg progesterone (i.m.; E/P, n=15),(2) 20 icrog GnRH analogue, buserelin (i.m.; GnRH, n=15),(3) 20 microg buserelin (i.m.) on Day 0 (T=0) and 500 microg prostaglandin on Day T+7 (GnRH/PG n=15),(4) transvaginal ultrasound-guided follicle ablation of all follicles > or =0.5 cm (ABL, n=15) or (5) 5 ml saline (i.m; Controls n=15). All camels were subsequently injected with 20 microg buserelin 14 days after the first treatment was given. The ovarian response was monitored daily by transrectal ultrasonography and the intervals from treatment to follicular wave emergence and also the day on which the new dominant follicle reached 1.3 cm was recorded. Amongst the treatment groups the mean interval from treatment to new follicle wave emergence and treatment to time taken for the new dominant follicle to reach 1.3 cm in diameter was shortest in the ABL group (2.3+/-0.5 days and 8.8+/-1.1 days respectively, P=0.044) and longest in the E/P group (6.4+/-0.8 days and 12.2+/-1.0 days respectively, P<0.001) whereas the GnRH and GnRH/PG groups were intermediate (3.0+/-0.5 days and 11.1+/-0.8 days GnRH; and 4.5+/-0.5 days and 10.7+/-0.7 days GnRH/PG). A total of 11/15 camels in both the GnRH and GnRH/PG groups had dominant follicles between 1.3 and 1.9 cm 14 days post treatment, of which 21 of the 22 follicles ovulated after GnRH injection on T+14. The ABL, E/P and control groups however, showed greater variability in follicle size with less camels having dominant follicles between 1.3 and 1.9 cm than the GnRH and GnRH/PG groups and more in the > or =2.0 cm or follicle regressing groups, therefore fewer of these camels ovulated (ABL n=7; E/P n=9; Control n=6) after GnRH injection on Day T+14. In conclusion, two GnRH injections 14 days apart or two GnRH injections 14 days apart and PG on Day 7 after the first GnRH were the most effective methods to synchronise ovulation rate in dromedary camels at a fixed time interval of 14 days after treatment.
Central Veterinary Research Laboratory, Dubai, United Arab Emirates. firstname.lastname@example.org
The purpose of this study was to evaluate seminal liquefaction and quality of ejaculated camel semen during storage in different extenders at room (23 degrees C) and refrigeration (4 degrees C) temperature. Semen was collected using an artificial vagina and diluted immediately (1:1), using a split-sample technique, in five extenders [(1) Tris-tes egg yolk,(2) Tris-lactose egg yolk,(3) citrate egg yolk,(4) sucrose egg yolk and (5) Tris-fructose egg yolk], while one fraction was kept without an extender to act as control. The semen was transported to the lab at 37 degrees C, in a portable incubator within half an hour, and thereafter liquefaction of semen was monitored every 15 min. After complete liquefaction of the semen it was evaluated for sperm concentration and morphology and then was extended to a final ratio of 1:3. Aliquots of each semen sample were then stored at refrigeration and room temperature. The average volume of an ejaculate was 4.3+/-0.4 mL and it had a very viscous consistency. The average concentration of spermatozoa was 230.4+/-10.7 x 10(6)mL(-1) and the proportion of spermatozoa with protoplasmic droplets averaged 1.02+/-0.2, while 2.7+/-0.6 and 9.7+/-2.9% had mid-piece and tail abnormalities, respectively. All extended semen samples liquefied within 1.5h at 37 degrees C, however, there was slow liquefaction in the sample without an added extender (control). Best liquefaction was observed in Tris-lactose extender followed by Tris-fructose and citrate egg yolk diluents whereas in the other two extenders there was head-to-head agglutination of the spermatozoa. There was no difference in the initial motility of the spermatozoa in extenders 1-5 after its liquefaction, however, after 24 and 48 h of storage a higher proportion of spermatozoa were motile in extenders 1, 2 and 4 (P<0.05) at both the temperatures. There was a gradual decline in viability of the spermatozoa in all extenders at both the temperatures, although, a high portion of the spermatozoa had intact acrosomes throughout the storage period. It may be concluded that dromedary semen, when added to an extender (1:1) immediately after collection, liquefies within 60-90 min at 37 degrees C. It maintains a high proportion of motile and viable spermatozoa that can survive storage up to 48 h in Tris-lactose egg yolk, Tris-tes egg yolk and sucrose egg yolk diluents. However, best liquefaction and progressive sperm motility is achieved in Tris-lactose egg yolk extender.
Agricultural Research Centre, Equine Research 32100 Ypäjä, Finland.
The aim of this study was to evaluate the quality of embryos and their recovery rate from mares inseminated at different intervals after ovulation. Finnhorse and warmblood mares were inseminated with fresh semen 8 to 16 h, 16 to 24 h, or 24 to 32 h after ovulation. Control mares were inseminated before ovulation. Sixty-seven embryo flushings were performed between Days 7 and 9 after ovulation/insemination. Thirteen mares were not flushed, but their uteri were scanned for pregnancy on Days 14 to 16. Embryo recovery rates decreased as time from ovulation to insemination increased, although embryo quality remained normal as evaluated by morphological criteria and mitotic index. However, postovulatory insemination in this trial appeared to delay embryo development, since the embryos recovered from mares inseminated after ovulation were appreciably smaller and at an earlier stage of development than control embryos recovered from mares inseminated prior to ovulation. Part of this delay in embryo development in the postovulation group could be due to the time needed for sperm capacitation. In addition, as the time from ovulation to insemination increased, embryo development might have been further delayed by defects in the aging oocyte.
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Department of Animal Health and Anatomy, Faculty of Veterinary, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain. email@example.com
Knowledge of the reproductive biology is critical for the development of management strategies of the species both in captivity and in the wild, and to address conservation concerns regarding the sustainable use of a species. The present report characterizes some aspects of the reproductive biology of the wild red brocket deer inhabiting the North-eastern Peruvian Amazon region, based on the anatomical and histological examination of the female reproductive organs of 89 wild adult females in different reproductive states. The red brocket deer female presented ovarian follicular waves involving the synchronous growth of a cohort of an average 25 follicles but only one follicle generally survived and continued development, reaching maturity at 4mm. Mean ovulation rate was 1.14 and litter size was 1 fetus. Females presented a low rate of reproductive wastage of 14.3% of embryos. Among the 89 adult females studied, 41 (46.1%) were pregnant and 48 (53.9%) were non-pregnant females. In the Northeastern Peruvian Amazon, conceptions occurred year-round in the red brocket deer but there were peaks in the rate of conception. Estimated yearly reproductive production was 0.76-0.82 young per adult female. Most pregnant females in advanced stage of pregnancy had at least one active CL, suggesting the persistence of CL throughout gestation.
J Alvarez, J Bezos, L de Juan, M Vordermeier, S Rodriguez, I G Fernandez-de-Mera, A Mateos, L Domínguez
Instituto de Investigación en Recursos Cinegéticos IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, Ciudad Real, Spain.
In spite of great efforts for its control and eradication, tuberculosis remains one of the most important zoonosis worldwide. Its causative agents, the members of the Mycobacterium tuberculosis complex, have a wide host range that complicates the epidemiology of this disease. Among susceptible species to these pathogens, camelids from the New World (llama, alpaca and vicuña) and Old World (Bactrian camel and dromedary) are acquiring an increasing importance in several European countries because of its growing number and could act as reservoirs of the disease for livestock and humans in their natural habitat. In addition, tuberculosis caused by a number of M. tuberculosis complex members is a life-threatening disease in these animal species. Although tuberculosis has been known to affect camelids for a long time, ante-mortem diagnosis is still challenging because of the lack of standardized diagnostic techniques and the limited sensitivity and specificity of the most widely applied tests. However, in recent years, several techniques that can at least partially overcome these limitations have been developed. This paper reviews the results and advances achieved in tuberculosis diagnosis in camelids in the last decade as well as the progresses on ongoing investigations, with special attention to the remaining challenges that still have to be faced to assure the availability of reliable tools for the detection of tuberculosis-infected animals and herds.
J Reprod Med. ;54 (11-12):691-7 20120903
Assisted reproductive technique outcome in testicular sperm extraction-intracytoplasmic sperm injection cycles with poor female response: a report on 8 years' experience.
Department of Obstetrics and Gynecology, Yeditepe University Hospital, Istanbul, Turkey. firstname.lastname@example.org
OBJECTIVE To evaluate the outcome in couples composed of azoospermia and a poor responder female undergoing assisted reproductive techniques (ARTs). STUDY DESIGN A retrospective study was performed involving 97 men suffering from nonobstructive azoospermia (NOA) whose partners had a poor response to ovarian stimulation. Poor response was defined as retrieval of fewer than 5 oocytes. Main outcome measures were implantation rate (IR), clinical pregnancy rate per embryo transfer (CPR/ET) and early pregnancy loss rate (EPLR). RESULTS Overall IR, CPR/ET and EPLR were found to be 16%, 23% and 15%, respectively, which were significantly lower than those in NOA men with normoresponder partners except EPLR (25%, 52% and 24%, respectively). When the results were further stratified according to number of oocytes retrieved and body mass index, no significant difference was observed between the groups. However, when the results were analyzed according to the woman's age, a significantly lower CPR/ ET was found in poor responder women aged > or = 38 years (11% vs. 33%; p = 0.03). CONCLUSION Although success of ART is suggested to be high once motil spermatozoa are found in testicular sperm extraction in NOA cases, poor response to ovarian stimulation might be considered as one of the strongest determinants of the outcome.
Theriogenology. 2009 Feb 3;: 19195696
Fixed-time AI pregnancy rate following insemination with frozen-thawed or fresh-extended semen in progesterone supplemented CO-Synch protocol in beef cows.
Department of Large Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, USA.
The objective of this study was to compare fixed-time AI pregnancy rate in Angus crossbred beef cows inseminated with frozen-thawed or fresh-extended semen. Two ejaculates from each of two Angus bulls were collected by artificial vagina and pooled for each bull. The pooled semen from each bull was divided into two aliquots; Aliquot 1 was extended using Caprogen((R))(LIC, Hamilton, New Zealand) to a concentration of 3x10(6)sperm/straw and Aliquot 2 was extended using egg-yolk-glycerol extender to a concentration of 20x10(6)sperm/straw. Semen extended with Caprogen((R)) was maintained at ambient temperature and semen extended with egg-yolk-glycerol extender was frozen and maintained at -196 degrees C until insemination. In each of two breeding seasons (Fall 2007 and Spring 2008), Angus-crossbeef cows (N=1455) at 12 locations were randomly assigned within location to semen type [Fresh (N=736) vs. Frozen (N=719)] and sire [1 (N=731) vs. 2 (N=724)]. All cows were synchronized with 100mug of GnRH im and a progesterone Controlled Internal Drug Release insert (CIDR) on Day 0, and on Day 7, 25mg of PGF2(alpha) im and CIDR removal. All cows received 100mug of GnRH im and were inseminated at a fixed-time on Day 10, 66h after CIDR removal. Timed-AI pregnancy rates were influenced by season (P<0.05), cows detected in estrus prior to and at AI (P<0.001), and dam age (P<0.01). Pregnancy rates were not affected by semen type (Fresh=51.5% vs. Frozen=50.4%; P=0.66) and there were no significant interactions of semen type by estrus expression, semen type by sire, or semen type by season (P>0.1). In conclusion, commercial beef cows inseminated with fresh-extended semen (3x10(6)sperm/straw) yielded comparable pregnancy rates to conventional frozen-thawed semen in a progesterone supplemented, CO-Synch fixed-time AI synchronization protocol and may provide an alternate to frozen semen for more efficient utilization of superior genetics.
Animal Reproduction Institute, Guangxi Key Laboratory of Subtropical Bioresource Conservation and Utilization, Guangxi University, Nanning 530005, China. email@example.com
Cloning of buffalos (Bubalus bubalis) through nuclear transfer is a potential alternative approach in genetic improvement of buffalos. However, to our knowledge, cloned offspring of buffalos derived from embryonic, fetal, or somatic cells have not yet been reported. Thus, factors affecting the nuclear transfer of buffalo somatic cells were examined, and the possibility of cloning buffalos was explored in the present study. Treatment of buffalo fibroblasts and granulosa cells with aphidicolin plus serum starvation resulted in more cells being arrested at the G0/G1 phase, the proportion of cells with DNA fragmentation being less, and the number of embryos derived from these cells that developed to blastocysts being greater. In addition, a difference was found in the development of embryos reconstructed with fetal fibroblasts from different individuals (P < 0.001). Forty-two blastocysts derived from granulosa cells and fetal fibroblasts were transferred into 21 recipient swamp buffalos, and 4 recipients were confirmed to be pregnant by rectal palpation on Day 60 of gestation. One recipient received two embryos from fetal fibroblasts aborted on Day 300 of gestation and delivered two female premature calves. Three recipients maintained pregnancy to term and delivered three female cloned calves after Days 338-349 of gestation. These results indicate that buffalo embryos derived from either fetal fibroblasts or granulosa cells can develop to the term of gestation and result in newborn calves.
Embryo development and embryo transfer in the European mink (Mustela lutreola), an endangered mustelid species.
Institute of Cytology and Genetics, Russian Academy of Sciences, Siberian Division, 630090, prosp. Lavrentjeva 10, Novosibirsk, Russia. firstname.lastname@example.org
The European mink is an endangered Mustelidae species and thus requires effective conservation measures, although little is known about reproduction in this species. In particular, preimplantation development has not been studied and, therefore, embryonic development and the growth of embryos was documented in the present study for European mink using light and fluorescent microscopy. Embryos develop in the oviducts and then migrate into the uterus on Day 6 post coitum (p.c.) at the morula stage. Embryos expanded as blastocysts from Day 7 until implantation on Day 12 p.c. Based on these findings, the use of embryo transfer for a conservation programme for the European mink was evaluated. Embryos were flushed from European mink resource females and transferred into the uterine horns of recipient hybrid females (honoriks and nohoriks). These hybrids were obtained by mating European polecat males with European mink females and vice versa. A total of 40 embryos was transferred and 20 live kits were born. The rates of pre- and postnatal survival were 50% and 70%, respectively. Both male and female offspring were lighter at birth in the embryo transfer group compared with naturally born controls, but there was no difference at 3 months of age.
[Preimplantation genetic diagnosis of chromosome abnormality by fluorescence in-situ hybridization].
Reproductive Medical Center, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China.
OBJECTIVE To perform preimplantation genetic diagnosis (PGD) of chromosome abnormality using fluorescence in-situ hybridization (FISH). METHODS Ten couples were presented for preimplantation genetic diagnosis. They had a total of 10 oocyte pick-up cycles. The collected oocytes were inseminated by intracytoplasmic sperm injection. PGD was carried out using cleavage-stage (day 3) embryo biopsy, fluorescence in-situ hybridization, and day 4 embryo transfer. RESULTS Ten oocyte pick-up cycles yielded 158 oocytes. Among the 94 embryos obtained, 54 embryos were biopsied and FISH analyses were performed for 51 blastomeres. Twenty-four embryos were transferred on the fourth day. There were 4 clinical pregnancies: 3 infants have been born, and 1 couple had ectopic pregnancy. CONCLUSION PGD is a valuable method to prevent the high risk of spontaneous miscarriages and conceiving chromosomally unbalanced offspring.
Sexual maturation and fertility of male Nigerian Dwarf goat (Capra hircus) clones produced by somatic cell nuclear transfer.
Nexia Biotechnologies, Inc., Vaudreuil-Dorion, and Department of Animal Science, McGill University, Ste Anne de Bellevue, QC, Canada.
Three, genetically identical, Nigerian Dwarf bucks produced by somatic cell nuclear transfer (NT) of fetal fibroblasts were monitored for sexual maturation and fertility. Starting at four months of age, these male clones were trained to serve an artificial vagina (AV). Average age of the NT-derived bucks at first semen collection was 20 weeks, which was not different from that of other young bucks of this breed (average age at first collection = 20 weeks). Average sperm production at 5 months of age for the NT-derived bucks was 5.0 x 10(8) spermatozoa, which was comparable to that of dwarf bucks of similar age (3.4 x 10(8) spermatozoa). At seven months of age, semen collected from two NT-derived bucks was used to artificially inseminate six females (three does per buck). Five does were confirmed pregnant by ultrasound at day 42. Nine healthy kids, four males and five females, were born in March and April 2000. Viable spermatozoa were collected from one of the F1 males at 28 weeks of age. These results demonstrated that NT-derived bucks and one of their male offspring developed sexually within the normal timeframe for their breed and that the clones were fertile.
Institute for Women's and Children's Health, Department of Obstetrics and Gynaecology, Sahlgrenska University Hospital, Östra, Göteborg S-416 85, Sweden.
In vitro fertilization (IVF) is a well established and effective method for the treatment of infertility, but there is concern about the health of children born as a result of this procedure. The introduction of new technologies, such as intracytoplasmic sperm injection (ICSI), has increased concern that the offspring from such techniques may be at increased risk, particularly of malformations. Studies on obstetric and neonatal outcome and early infant development after IVF obtained from a Medline search were reviewed. Children born after IVF had a considerably higher risk of being born pre-term and with a lower birth weight than children conceived naturally. A high incidence of multiple births and maternal characteristics were the main factors responsible for the increase in adverse outcome. Novel strategies in assisted reproduction, including the development of single embryo transfer regimens and avoidance of multiple births, are required. There is also a need for further developmental follow-up of children born after assisted conception, especially those born after ICSI.
[Incidence of chromosomal anomalies and congenital malformations in children born from assisted fertilization].
Centro Sterilità, Divisione Ostetricia e Ginecologia, ASMN Reggio Emilia.
The introduction and widespread application of Assisted Reproductive Techniques (ART) have raised major concern about the offspring 's health. The incidence of congenital and chromosomal anomalies after standard In Vitro Fertilization and Embryo Transfer seems to be similar to that expected in the general population. The prevalence of congenital malformations does not seem to be higher in children conceived by ICSI. On the other hand, it seems that there is a slight risk for transmission of chromosomal aberration of paternal origin and a certain risk of de novo sex-chromosomal and structural aberrations after ICSI. We report the results of the follow-up of 938 children conceived in our public ART by standard IVF(649) and by ICSI(289) from 21-2-1987 to 30-6-1999. The incidence of the congenital malformations results of the 1.8%(17/938); the incidence of chromosomal anomalies results 0.5%(5/938). The incidence of congenital malformations and chromosomal anomalies results 1.5%(10/649) and 0.6%(4/649), respectively, for standard IVF and 2.4%(7/289) and 0.3%(1/289) for ICSI. Our data seems to be reassuring but the incidence of chromosomal anomalies in ICSI children needs further investigation.