Identification of proAKAP4 concentration variations in dromedary sperm and their correlation with monthly semen parameters.

Unlabelled: ProAKAP4 is synthetized as a precursor polypeptide that must be converted into mature AKAP4 in living spermatozoa and is considered as a functional marker of spermatozoa. The gene is well-conserved in mammals although uncharacterized in Camelidae. In the present study, we investigate the expression metabolism of proAKAP4 and AKAP4 proteins and evaluate their seasonal dynamics relative to semen quality in dromedary camels.

Interaction among extenders, cryoprotectants and Orvus Es Paste supplementation and freezing rate for sperm cryopreservation in the dromedary camel.

This study evaluated the effects of freezing extenders, cryoprotectants and their concentrations, presence of Orvus Es Paste and freezing rates for cryopreserving dromedary camel sperm. Semen (five males; 2 ejaculates/male) was frozen in one of the following extenders (Green Buffer or INRA96 ), cryoprotectants (3 and 6% glycerol or ethylene glycol), with or without Orvus Es Paste and freezing at two different heights (1 and 4 cm) above liquid nitrogen. Sperm motility recovery parameters were evaluated post-thaw (0 and 1 hr), vitality and acrosome integrity (0 hr).

"Comparison of two closed vitrification methods for vitrifying dromedary camel (Camelus dromedarius) embryos".

A total of 184 dromedary camel embryos were vitrified using a novel vitrification kit specifically developed for camel embryos. These embryos were vitrified using a 3-step process by exposing them to vitrification solutions (VS) containing 20% foetal calf serum (FCS) with (+) or without (-) the addition of bovine serum albumin (BSA). Embryos were then further divided into two groups ( View Article and Find Full Text PDF

Individual male dependent improvement in post-thaw dromedary camel sperm quality after addition of catalase.

Cryopreservation is stressful to sperm cells inducing an increase in the production of reactive oxygen species and subsequently reducing post-thaw sperm quality. With the present study, there was evaluation of the protective effects of two antioxidants, epigallocatechin (1 mM) and catalase (500 IU/ml), added at thawing, as well as inter-individual variation on quality of cryopreserved dromedary camel spermatozoa. Semen was collected from six males and sperm, selected using single layer centrifugation, were cryopreserved.

Near-Newtonian Blood Behavior - Is It Good to Be a Camel?

From a certain level of exercise-intensity onward, hematocrit increases in horses, which brings more oxygen carriers into the bloodstream. Camels, however, when used in competitive racing could be even in need of iron supplementation and blood transfusions due to a severe reduction of their available hematocrit compared to their resting hematocrit. Since the extrinsic and intrinsic mechanical properties of camel erythrocytes (RBC) are so different compared to RBCs of other mammals, the question arises whether this observation might be a response to endurance exercise aiming at keeping the RBC count low.

The use of some assisted reproductive technologies in old world camelids.

The use of camels for racing, milking and as show animals is growing in popularity, thus there is increased enthusiasm to breed more of the genetically superior animals. This review highlights recent developments in assisted reproductive techniques in camels, such as embryo transfer and artificial insemination, to ensure more rapid genetic progress. This paper discusses the difficulties involved in handling the semen due to its high viscosity and ways to reduce it.

Effect of different freezing rates and thawing temperatures on cryosurvival of dromedary camel spermatozoa.

The objective of this study was to evaluate the effect of different freezing rates and thawing temperatures on the post-thaw quality of camel spermatozoa. Ten ejaculates from five male camels were frozen at five different freezing rates, achieved by placing the straws at specific heights above the surface of liquid nitrogen for different lengths of time (4 cm for 15 min; 1 cm for 15 min; 7 cm for 15 min; 7 cm for 5 min + 4 cm for 3 min; 4 cm for 5 min + 1 cm for 3 min) followed by storage in liquid nitrogen. Two thawing temperatures (37° for 30 s and 60 °C for 10 s) were subsequently tested.

Donor sperm production in heterologous recipients by testis germ cell transplantation in the dromedary camel.

The object of this study was to investigate if testis germ cell transplantation (TGCT) into a heterologous recipient would result in donor-origin spermatogenesis in the dromedary camel. First, we investigated a workable protocol for TGCT in camels, including donor cell isolation, enrichment by density gradient centrifugation (Percoll and Bovicoll), rete testis injection and microsatellite detection of donor and recipient genotypes. Second, the effects of three doses of Dolichos biflorus agglutinin (DBA), a glycoprotein that specifically binds to gonocytes or Type A spermatogonia, on testis germ cell depletion were investigated by direct injection into the rete testis of a male camel.

Temperature dependency of whole blood viscosity and red cell properties in desert ungulates: Studies on scimitar-horned oryx and dromedary camel.

Background: The dromedary camel and the oryx antelope are exposed to excessive heat and solar radiation in their desert habitat. Desertification of areas with by now little rainfall may occur eventually. Well-adapted large animal species show us what is needed to survive in scorching regions.

An update on semen collection, preservation and artificial insemination in the dromedary camel (Camelus dromedarius).

Artificial insemination (AI) in domestic animals is an important tool to maximise the use of genetically superior males and thereby insure rapid genetic progress. However, the application of AI in camelids has been hindered by the difficulties involved in collecting, as well as handling the semen due to the viscous nature of the seminal plasma. This review describes the challenges of semen collection and discusses the role of seminal plasma as well as the reasons for the viscosity and how to liquefy it so that ejaculates can be more accurately evaluated.

Colloid centrifugation of fresh semen improves post-thaw quality of cryopreserved dromedary camel spermatozoa.

Colloids have been successfully used in a number of species to improve sperm populations for IVF and for cryopreservation The usefulness of Single Layer Centrifugation (SLC) for freezing dromedary camel spermatozoa in two different extenders was evaluated by examining the motility, viability, acrosome status, DNA integrity, and ability of cryopreserved sperm to penetrate oocytes in vitro in a heterologus IVF system. Two ejaculates from each of five males were divided into four aliquots: two were processed by SLC (selected) while two were centrifuged without colloid (control). Pellets were cryopreserved in Green Buffer or INRA-96® containing 3% glycerol and evaluated at 0 and 1 h post thawed.

Optimization of the cryopreservation of dromedary camel semen: Cryoprotectants and their concentration and equilibration times.

Research into an optimal cryoprotectant, its concentration and equilibration time underlies the successful cryopreservation of dromedary camel spermatozoa. This study assessed the cryo-efficiency of different cryoprotectants, their concentration and equilibration time and any interactions. In experiment 1, semen samples (n = 4 males; 2 ejaculates/male) were frozen using Green Buffer containing one of four cryoprotectants (3% glycerol, ethylene glycol, methyl formamide, dimethyl sulfoxide) and using 4 equilibration times (10 min, 0.

Evaluation of cholesterol- treated dromedary camel sperm function by heterologous IVF and AI.

Cholesterol (cholesterol-loaded cyclodextrins: CLC) treatment of dromedary camel sperm prior to freezing enhances cryosurvival. The present study first validated the efficacy of a heterologous zona-free goat oocyte assay (n=115 oocytes) to evaluate camel sperm function in vitro (Experiment 1: n=6 bulls), then examined the effects of CLC treatment (1.5mg/mL CLC; CLC+) versus no treatment (0 CLC) of fresh (Experiment 2: n=4 bulls) and frozen-thawed (Experiment 3: n=5 bulls) camel sperm to penetrate, de-condense and form pro-nuclei in in vitro-matured goat oocytes.

Cholesterol addition aids the cryopreservation of dromedary camel (Camelus dromedarius) spermatozoa.

The cryopreservation of dromedary camel (Camelus dromedarius) sperm has proved challenging with little success reported. The routine application of artificial insemination with frozen semen would assist the flow of valuable genetic material nationally and internationally. The current study sought to examine the effects of cholesterol (cholesterol-loaded cyclodextrin [CLC]) preloading on camel sperm cryosurvival.

Patterning and post-patterning modes of evolutionary digit loss in mammals.

A reduction in the number of digits has evolved many times in tetrapods, particularly in cursorial mammals that travel over deserts and plains, yet the underlying developmental mechanisms have remained elusive. Here we show that digit loss can occur both during early limb patterning and at later post-patterning stages of chondrogenesis. In the 'odd-toed' jerboa (Dipus sagitta) and horse and the 'even-toed' camel, extensive cell death sculpts the tissue around the remaining toes.

Reproductive physiology in female Old World Camelids.

This review summarizes the basic reproductive physiology of dromedary and Bactrian camels. Camels are seasonal breeders with a relatively short breeding season during the cooler months. The onset of the breeding season can be influenced by local environmental factors such as temperature and pasture availability although decreased libido of the male as the environmental temperature increases is also a factor.

Cross-species chromosome painting among camel, cattle, pig and human: further insights into the putative Cetartiodactyla ancestral karyotype.

The great karyotypic differences between camel, cattle and pig, three important domestic animals, have been a challenge for comparative cytogenetic studies based on conventional cytogenetic approaches. To construct a genome-wide comparative chromosome map among these artiodactyls, we made a set of chromosome painting probes from the dromedary camel (Camelus dromedarius) by flow sorting and degenerate oligonucleotide primed-PCR. The painting probes were first used to characterize the karyotypes of the dromedary camel (C.

Embryo transfer in the dromedary camel (Camelus dromedarius) using asynchronous, meclofenamic acid-treated recipients.

A total of 40 (Day 7) embryos were recovered from the uteri of 10 superovulated camels. Recipient camels (n = 30) were prepared by injection with 20 (1/4)g of the gonadotrophin-releasing hormone analogue buserelin (i.v.

Investigation of factors affecting pregnancy rate after embryo transfer in the dromedary camel.

The uteri of 36 adult dromedary camels were flushed non-surgically three times each with 90-120 mL of embryo flushing medium 7 days after ovulation. A total of 242 embryos were recovered, of which 139 were transferred non-surgically to recipient camels that were either at different levels of synchrony with respect to the Day 7 donor (+1 to -3 days; n = 58), or were at Day 6 after ovulation, but received one of the following treatments: (i) none (controls, n = 15); (ii) 150 mg progesterone-in-oil injected intramuscularly once daily during Days 5-20 after ovulation inclusive (n = 16); (iii) 500 mg flunixin meglumine given intravenously 15 min before transfer of the embryo (n = 6); (iv) 20 microg of the gonadotrophin-releasing hormone (GnRH) analogue buserelin given on Day 5 after ovulation (n = 12); or (v) the embryo was cooled to 4 degrees C and held at this temperature in an insulated container for 24 h before being transferred (n = 32). Jugular vein blood samples, taken daily from all the recipient camels during Days 0-20 after ovulation, were assayed for progesterone concentration and closely timed serial samples taken from the camels receiving flunixin meglumine or GnRH were assayed for 13,14-dihydro-15-keto prostaglandin F2alpha (PGFM) or oestradiol concentrations.