Fetal gender prediction by monitoring circulating steroid hormones and some biochemical parameters in maternal dromedary camels.

To predict the sex of the foetus, healthy pregnant dromedary camels (n = 24) were included. Blood samples were collected for measurements of progesterone, estradiol, testosterone, and cortisol as well as total proteins, albumin, glucose, creatinine, blood urea nitrogen, phosphorus, calcium, creatine kinase, alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), calcium, phosphorus, and magnesium. Statistical analysis revealed differences between pregnant camels and pregnant camels in terms of female or male foetuses depending on the actual sex of the born calf. The results revealed that testosterone and ALP concentrations were significantly (P < 0.001) greater in camels given to males than in those given to calves. There were strong positive correlations between male calf birth and testosterone and ALP concentrations (r = 0.864; P < 0.0001 and r = 0.637; P < 0.001, respectively). On the other hand, the cortisol, glucose and creatinine concentrations were significantly lower (P lower in camel calved males than in females). There were significant negative correlations between male calf birth and the cortisol, glucose and creatinine concentrations (r =-0.401; P = 0.052; r =-0.445; P = 0.029 and r =-0.400; P = 0.053, respectively). The concentrations of calcium, phosphorus, calcium/phosphorus ratio, magnesium, and albumin and the albumin/globulin ratio were not significantly different (P > 0.05) between the two groups. In conclusion, testosterone could be used as a biomarker to determine the sex of foetuses in dromedary camels.

Leukocyte populations in peripheral blood of dromedary camels with clinical endometritis.

Endometritis represents the main cause of reproductive failure in dromedary camels. In dromedary camels, associations between endometritis-causing pathogen-species, disease severity, and systemic changes in the immune system have not been evaluated. In the current study, there was use of flow cytometry and immunofluorescence of membrane proteins for the evaluation of leukocyte subsets and the cellular phenotype in blood of camels with clinical endometritis and evaluations of associations with disease severity and endometritis-causing pathogens. Animals with endometritis had markedly larger numbers of total leukocytes and neutrophils. Although total lymphocyte and monocyte counts did not differ between camels with and without clinical endometritis, there were lesser numbers of total and effector CD4-positive T cells in camels with endometritis. Among monocytes, number of camel inflammatory monocytes (Mo-II) was markedly greater, whereas Mo-III numbers were less in the blood of camels with clinical endometritis. Number of inflammatory monocytes was also indicative of endometritis severity grade. Among camels with clinical endometritis, E. coli- and S. aureus-infected animals had similar endometritis grades and comparable phenotype and composition patterns of leukocytes. Neutrophils and monocytes of camels with clinical endometritis had fewer cell adhesion molecules (i.e., CD11a and CD18). Collectively, the results from the current study allowed for identification of associations between endometritis severity grade and larger numbers of inflammatory monocytes. The results also indicate there is no association between endometritis pathogen-species and changes in phenotype or composition of blood leukocytes.

Effect of heavy metals arsenic, cadmium, and lead on the semen variables of dromedary camels (Camelus dromedarius).

In this study, there was investigation of the effect of heavy metals on the fertility of dromedary camels. Fourteen camels at the Camel Research Center, King Faisal University, and 41 infertile dromedaries admitted to the Veterinary Teaching Hospital were used for semen evaluation during the breeding season. Seminal plasma and blood serum were collected from all males until analysis. Concentrations of three heavy metals [arsenic (As), cadmium (Cd), and lead (Pb)] were determined in the seminal plasma and serum using an atomic absorption spectrophotometer. The results indicate there are differences (P < 0.05 - P < 0.01) in pH, sperm motility, sperm concentration, and sperm abnormalities between the fertile and infertile male camels. In seminal plasma, there were marked differences (P < 0.01- P < 0.0001) between the control and infertile male camels in As, Cd, and Pb concentrations. In serum, there were differences (P < 0.01 - P < 0.001) between the fertile and infertile camels in serum As, Cd, and Pb concentrations. There was a positive correlation (P < 0.05; r = 0.77 and r = 0.94, respectively) between serum and seminal plasma concentrations of both As and Cd in the infertile dromedaries. In the control group, there was a positive correlation (P < 0.05; r = 0.70) between seminal plasma concentrations of Cd and percent sperm abnormalities. In conclusion, relatively greater seminal plasma and serum concentrations of As, Cd, and Pb are associated with lesser values for semen quality variables and infertility in dromedary camels.

The effect of subclinical mastitis on the concentration of immunoglobulins A, G, and M, total antioxidant capacity, zinc, iron, total proteins, and calcium in she-camel blood in relation with pathogens present in the udder.

The present study aims to evaluate the amount of immunoglobulins A, G, and M in she-camel blood serum in relation with the presence of pathogens in the udder, and to compare the antioxidative capacity and the concentration of zinc, iron, total proteins, and calcium. Milk and blood samples from she-camels from south Jordan were taken; according to milk bacteriological examination, the animals were divided into two groups: (Gm) which contained samples of milk contaminated with bacteria and (Gh) which contained uncontaminated milk samples. Milk and blood were sampled from 30 females and examined for the concentration of immunoglobulins A, G, and M and for the presence of pathogens in milk. Total antioxidant capacity, zinc, iron, total proteins, and calcium concentrations in blood were determined. Milk samples were checked for the presence of pathogens. She-camels for the study were of similar age and productivity in the middle stage of lactation. It was determined that the presence of pathogenic bacteria infecting the udder quarters had considerably influenced the values of immunoglobulins G, A, and M, total antioxidant capacity, and zinc and total protein concentration (p < 0.05) in blood serum; no significant difference in iron and calcium concentration was determined. Subclinical mastitis has a crucial role in increasing the concentration of immunoglobulins in serum; some parameters measured in blood (zinc, total antioxidant capacity, total proteins) could be indicative for the presence of inflammation in she-camels.

Accumulation, Persistence, and Effects of Indospicine Residues in Camels Fed Indigofera Plant.

Indospicine (l-2-amino-6-amidinohexanoic acid) is a natural hepatotoxin found in all parts of some Indigofera plants such as Indigofera linnaei and Indigofera spicata. Several studies have documented a susceptibility to this hepatotoxin in different species of animals, including cattle, sheep, dogs, and rats, which are associated with mild to severe liver disease after prolonged ingestion. However, there is little published data on the effects of this hepatotoxin in camels, even though Indigofera plants are known to be palatable to camels in central Australia. The secondary poisoning of dogs after prolonged dietary exposure to residual indospicine in camel muscle has raised additional food safety concerns. In this study, a feeding experiment was conducted to investigate the in vivo accumulation, excretion, distribution, and histopathological effects of dietary indospicine on camels. Six young camels (2-4 years old), weighing 270-390 kg, were fed daily a roughage diet consisting of Rhodes grass hay and lucerne chaff, supplemented with Indigofera and steam-flaked barley. Indigofera (I. spicata) was offered at 597 mg DM/kg body weight (bw)/day, designed to deliver 337 µg indospicine/kg bw/day, and fed for a period of 32 days. Blood and muscle biopsies were collected over the period of the study. Concentrations of indospicine in the plasma and muscle biopsy samples were quantitated by validated ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The highest concentrations in plasma (1.01 mg/L) and muscle (2.63 mg/kg fresh weight (fw)) were found at necropsy (day 33). Other tissues were also collected at necropsy, and analysis showed ubiquitous distribution of indospicine, with the highest indospicine accumulation detected in the pancreas (4.86 ± 0.56 mg/kg fw) and liver (3.60 ± 1.34 mg/kg fw), followed by the muscle, heart, and kidney. Histopathological examination of liver tissue showed multiple small foci of predominantly mononuclear inflammatory cells. After cessation of Indigofera intake, indospicine present in plasma in the remaining three camels had a longer terminal elimination half-life (18.6 days) than muscle (15.9 days), and both demonstrated monoexponential decreases.

Effect of dystocia on some hormonal and biochemical parameters in the one-humped camel (Camelus dromedarius).

The present study compared some of the hormonal and biochemical constituents of serum from eutocic and dystocic one-humped camels (Camelus dromedarius). Sera were harvested from eutocic (n = 9) and dystocic (n = 20) camels within the first 15 minutes after delivery. Although there were no differences in the concentrations of estradiol-17ß (E2) and prostaglandin F2α (PGF2α) between the eutocic and the dystocic animals, the level of progesterone (P4) and cortisol was significantly higher (P < 0.01) in animals that experienced dystocia than those that had a normal birth. There were no differences between the concentrations of alkaline phosphatase, aspartate aminotransferase, calcium, cholesterol, creatine kinase, creatinine, or magnesium (Mg) in eutocic and dystocic animals. The nitric oxide concentration was significantly higher (P < 0.01) in the serum from animals with dystocia than those that had normal births. By contrast, the serum concentrations of glucose, phosphorus (P), and triglycerides were significantly lower (P < 0.01) in eutocic camels compared with dystocic camels. As the delayed decline of P4 is reported to be the major hormonal difference between eutocic and dystocic camels, we propose that the insensitivity of corpus luteum to luteolytic action may be a cause of dystocia. Moreover, stress and hormonal changes may affect the metabolic traits in dystocia camels.

Biochemical and hormonal analysis of follicular fluid and serum of female dromedary camels (Camelus dromedarius) with different sized ovarian follicles.

The current study aimed to compare some biochemical and hormonal constituents in follicular fluids and serum of female dromedary camels with different sized ovarian follicles. Therefore, follicular fluids from follicles sized 1.1-1.5cm (n=10), 1.6-2.1cm (n=10) and 2.2-2.5cm (n=10) and sera were harvested from 20 female camels. The concentrations of ascorbic acid, glucose, cholesterol and activities of acid phosphatase (ACP) and alkaline phosphatase (ALP) were not changed significantly neither in follicular fluids of all follicle sizes nor in sera of female camels with different sized follicles. The concentrations of estradiol-17ß (E2) in the follicular fluid of follicles sized 2.2-2.5cm were significantly lower (P<0.01) than its corresponding value in follicular fluid of other follicle sizes. The concentrations of progesterone (P4), tri-iodothyronine (T3), thyroxin (T4), cortisol and insulin-like growth factor-1 (IGF-1) remained comparable in follicular fluids of all examined different sized follicles. The concentrations of E2, P4, T3, T4, cortisol and IGF-1 were similar in the serum of camels with different sized follicles. Interestingly, mean concentrations of P4 and IGF-1 in follicular fluids were higher than their corresponding values in sera of camels with different sized follicles and the mean concentrations of glucose, cholesterol, ALP and cortisol in sera were higher than their corresponding values in follicular fluids of the examined camels. With the exception of E2, there were no significant differences in biochemical and hormonal constituents between follicular fluids from different sized follicles.

Molecular detection of bovine leukemia virus in peripheral blood of Iranian cattle, camel and sheep.

Bovine leukemia virus (BLV) is a deltaretrovirus which infects and induces proliferation of B-lymphocytes in the peripheral blood circulation and in lymphoid organs primarily of cattle, leading to leukemia/lymphoma. This study was carried out to investigate the presence of BLV in cattle, sheep and camels from the Chaharmahal va Bakhtiary and Isfahan provinces in Iran. A total of 874 blood samples collected from cattle, sheep and camels were used in this study to detect BLV using a nested-PCR. The results from this study indicated that 17.2% (n=874) of all blood samples collected were positive for BLV. The percentages of blood samples positive for BLV from cattle, sheep and camels were 22.1 (n=657), 5.3 (n=95) and 0 (n=122) respectively. The results from this study showed that BLV infected cattle and sheep. Camels seemed to be resistant to BLV infection. This study contributes to the nationwide effort to obtain baseline information on the prevalence of BLV, which will assist in planning the control strategy for the disease in Iran.

Effect of pregnancy and embryonic mortality on milk production in dromedary camels (Camelus dromedarius).

The main objective of the present study was to compare milk production in pregnant versus nonpregnant dromedary camels. In addition, we described the effect of embryonic mortality on lactation and measured serum progesterone levels until d 60 to 90 of gestation. Twenty-five multiparous camels were selected in midlactation for 2 studies in consecutive years. Camels were mated naturally when the size of the dominant follicle reached 1.2 to 1.5cm. Pregnancy was diagnosed by ultrasonography and progesterone determination. In the first experiment (Exp 1), 8 of 11 animals conceived at 284±21.5d postpartum. Three pregnant dromedaries were given PGF2α to induce luteolysis and pregnancy loss on d 62 and spontaneous embryonic loss was detected in 2 camels (on d 27 and 60). Animals were allotted to 3 groups retrospectively: nonpregnant camels (group 1, n=4), pregnant camels (group 2; n=3), and camels with embryonic loss after d 55 (group 3; n=4). In the second study (Exp 2), 14 dromedaries were mated during midlactation. Seven of them failed to conceive (group 1) and 7 became pregnant (group 2). No embryonic loss was detected in Exp 2. Turning points in milk production were identified by change point analysis. In nonpregnant dromedaries (group 1), milk decreased slowly over time without significant change point. In pregnant camels (group 2), a gradual decline until 4 wk after mating was followed by a sudden drop, and the change point model resulted in one breakpoint at d 28±7 and 35±3 of gestation in Exp 1 and Exp 2, respectively. In camels with embryonic mortality (group 3, Exp 1), milk yield started to decline similarly as in pregnant animals, but milk production increased gradually after embryonic loss and reached similar levels as in their nonpregnant herdmates. Change point analysis for group 3 resulted in 2 turning points at 30±4 and 48±4d after conception. Mean length of lactation was shorter by 230 (34.2%) and by 249d (37.6%) and mean total lactation production was decreased by 1,532 (31.6%) and 2,151 kg (44.3%) in pregnant compared with nonpregnant camels in Exp 1 and Exp 2, respectively. We concluded that the calving interval can be shortened by mating during midlactation. However, pregnancy has a strong negative effect on milk production as dromedaries stop lactating by the fourth month of gestation. Following embryonic mortality within 3mo of conception, milk production is restored.

Effects of dehydration and blockade of angiotensin II AT1 receptor on stress hormones and anti-oxidants in the one-humped camel.

BACKGROUND: The objective of this study was to provide for the first time data on plasma catecholamines, cortisol, glutathione and malondialdehyde after long term dehydration (20 days) in the presence and absence of angiotensin II (Ang II) AT1 receptor blocker (losartan) versus levels in time-matched, non-dehydrated control camels and to record the responses of glutathione and malondialdehyde activity in liver and kidney homogenates in control, dehydrated-losartan treated and dehydrated camels. Eighteen male camels were studied, six hydrated (control group), six dehydrated and treated with losartan (treated group) and six dehydrated not treated (dehydrated). RESULTS: Plasma levels of norepinephrine and dopamine were significantly increased (P < 0.01) in both treated and dehydrated groups compared to time matched control, whereas Plasma epinephrine level showed significant decrease (P < 0.05) in both treated and dehydrated groups compared to control. Plasma cortisol also showed significant increase (P < 0.01) in both treated and dehydrated groups compared to control. Glutathione levels in plasma, liver and kidney homogenates for both treated and dehydrated groups reveled significant increase (P < 0.05) Likewise, malondialdehyde levels in plasma, liver and kidney homogenates were substantially and significantly increased in both treated and dehydrated groups. CONCLUSION: In conclusion, the results of this study demonstrated that dehydration substantially increased the circulating levels of norepinephrine, dopamine and cortisol but decreased plasma epinephrine. Similarly, losartan showed similar effects to that of dehydration. In addition, this investigation showed dehydration alone or in combination with losartan induced significant increments in glutathione and malondialdehyde activities in plasma, liver and kidney homogenates, presumably in order to counteract the potentially damaging effects of free radicals. Blockade of angiotensin II AT1 receptors did not alter significantly the response of dehydration in any of these indices.

Immunization against GnRH in the male camel (Camelus dromedarius): effects on sexual behavior, testicular volume, semen characteristics and serum testosterone concentrations.

The effect of immunization against gonadotrophin releasing hormone (GnRH) on sexual behavior, total scrotal size, semen characteristics and serum concentrations of testosterone, was evaluated for 24 wks in sexually mature camels (Camelus dromedarius). Eight bull camels were randomly divided into a treatment and control group. Four male camels were immunized using 2 mg GnRH - tandem-dimer conjugated to ovalbumin, (Pepscan Systems, the Netherlands) administered subcutaneously, 4 wks apart. Control male camels received the same amount of saline solution. Significant decline in serum testosterone level was observed in three immunized camels out of four, whereas one camel showed no effect. The testosterone levels reached to <1.0 ng/mL serum by week 4 after booster injection and remained suppressed through the course of the study. The total testicular volume was not affected until the end of the experiment. In treated animals, the sexual behavior negatively affected after the booster injection. Anti-GnRH vaccine had a seriously detrimental effect on the acrosin amidase activity and normal acrosome percentages in treated male camels. It is concluded that the vaccine was effective in reducing serum testosterone levels and libido, and it had a serious harmful effect on the acrosin amidase activity and percentages of spermatozoa with normal acrosome. The immunogen did not affect the total testicular volume.

Embryo transfer in the dromedary camel (Camelus dromedarius) using non-ovulated and ovulated, asynchronous progesterone-treated recipients.

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.

Circulating oxidative stress status in dromedary camels infested with sarcoptic mange.

Oxidative stress is an imbalance between radical-generating and radical-scavenging activity, resulting in oxidation products and tissue damage. This study was aimed to evaluate the status of oxidative stress indices in blood of camels naturally infested with S. scabiei. Forty-seven male camels (Camelus dromedaries) were divided according to the extent of the infested area with Sarcoptes scabiei into four groups, mild (MID, n = 12), moderate (MOD, n = 10), severely infested (SEV, n = 10) and healthy control group (n = 15). Blood was used for determination of red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV), serum nitric oxide (NO(•), a free radical), ascorbate and albumin concentrations, and erythrocytic values of malondialdehyde (MDA, a marker of lipid peroxidation), protein carbonyls (PC, an indicator of protein oxidation), glutathione (GSH) superoxide dismutase (SOD) and catalase (CAT). Decreased levels (P < 0.05) of RBC, Hb, PCV, albumin and ascorbate were noticed in MOD and SEV compared to controls with the lowest values (P < 0.05) in SEV except for ascorbate, where MOD did not differ from SEV. Compared to controls, NO(•) gradually increased (P < 0.05) in MID followed by MOD and SEV, whereas MDA and PC were higher (P < 0.05) in MOD and SEV. PC was higher (P < 0.05) in MOD than SEV. In addition, the antioxidants GSH, SOD and CAT were higher (P < 0.05) in MID and lower (P < 0.05) in MOD and SEV compared to controls. GSH was lower (P < 0.05) in SEV compared to MOD. Besides, Hb was negatively correlated with NO(•) (r = -0.68, P < 0.001), MDA (r = -0.53, P < 0.001) and PC (r = -0.73, P < 0.001). In conclusion, dromedary sarcoptosis is accompanied by a state of oxidative stress process, which increased by increasing the area of infestation, and may contribute to the pathogenesis of the disease.

Hormonal, biochemical, and hematological profiles in female camels (Camelus dromedarius) affected with reproductive disorders.

The aim of this study was to assess the blood profiles in female camels affected with common reproductive disorders. Estradiol-17beta (E(2)), progesterone (P(4)), thyroxin (T(4)), zinc (Zn), copper (Cu), calcium (Ca), phosphorus (P), magnesium (Mg), cholesterol, glucose, triglycerides, total protein, albumin, globulin, hematocrite, and total and differential white blood cell counts (WBC) were determined in blood of female camels affected with endometritis (n=15), vaginal adhesions (n=15), and ovarian cysts (n=15). Normal cyclic animals were used as controls (n=15). Diagnosis of reproductive disorders was based on transrectal palpation, ultrasonographic examination, and exploration of the vagina. Increased WBC counts (P=0.03) and a tendency for neutrophelia (P=0.05) were noted in female camels with vaginal adhesions. These animals were also characterized by having higher concentration of serum P(4) (P=0.0001), T(4) (P=0.001) and total protein (P=0.007), in comparison with female camels with endometritis, ovarian cysts, or controls. Animals having ovarian cysts with thin walls and homogenous hypoechogenic contents had greater serum E(2) (P=0.001) and P(4) (P=0.0001) than those having ovarian cysts with thick walls and non-homogenous echogenic contents. Animals with endometritis, vaginal adhesions, and ovarian cysts revealed lower serum Zn concentration than that of control group (P=0.003). Other blood parameters did not differ significantly compared to controls. In conclusion, this is the first report characterizing blood constituents in female camels with various reproductive disorders. These profiles may be valuable in clarifying the etio-pathogenesis of these disorders.

The concentrations of LH, FSH, oestradiol-17beta and progesterone in the blood plasma of the female Bactrian camel (Camelus bactrianus) before and after intramuscular injection of seminal plasma.

The concentrations of LH, FSH, oestradiol-17beta and progesterone in the blood plasma of the female Bactrian camel (Camelus bactrianus) before and after intramuscular injection of seminal plasma.

Phospholipid- and fatty acid-composition in the erythrocyte membrane of the one-humped camel [Camelus dromedarius] and its influence on vesicle properties prepared from these lipids.

The lipid composition of the membrane of erythrocytes from the one-humped camel (Camelus dromedarius) concerning the different lipid classes and the fatty acids was investigated for the first time. The most frequently occurring lipids are sphingomyelin (28.8% of total lipids), phosphatidylcholine and phosphatidylserine (each about 12%). The cholesterol/lipid ratio was calculated to be 0.30 (w/w). The fatty acids consist of shorter and/or more unsaturated chains, which resulted in a more fluid membrane compared to human RBC membranes. Liposomes prepared from erythrocyte lipid extracts were used to investigate the membrane properties resulting from this special lipid mixture. These vesicles were sufficient stable in buffer and significantly more stable than vesicles prepared from human erythrocyte lipid extracts in serum at 37 degrees C. Lipoplexes prepared from cationic erythrocyte lipid liposomes and a reporter gene showed in vitro an improved transfection on two colon carcinoma cells with an enhancement of up to 400% in beta-galactosidase activity in comparison to Lipofectin.

Serum progesterone and 17 beta-estradiol concentrations during pregnancy of Bactrian camel (Camelus bactrianus).

Serum progesterone and 17 beta-estradiol during pregnancy in the Bactrian camel were measured by radioimmunoassay. Serum progesterone concentrations increased by 15 d after artificial insemination (AI) and remained elevated throughout most of gestation, the mean concentrations (3.06 +/- 0.49 to 8.51 +/- 4.80 ng/mL) were similar to those reported for many species during the same stage of pregnancy. Serum 17 beta-estradiol increased significantly from 11 m.o. of pregnancy with peak mean concentrations of 617.47 +/- 32.56 pg/mL at the 11.5 m.o.

Preliminary comparative studies on complement fixation, dot enzyme immunoassay, and western blotting for the detection of antibodies to Mycoplasma mycoides subspecies mycoides SC in Nigerian camel (Camelus dromedarius).

The serological prevalence of antibodies to Mycoplasma mycoides subsp. mycoides SC, the aetiological agent of contagious bovine pleuropneumonia (CBPP), was investigated in Nigerian camels. Fifty-eight serum samples were collected from slaughtered camels and examined by complement fixation (CFT), dot enzyme immunoassay and Western blots. Fourteen of the slaughtered camels examined had pneumonic lesions. All sera examined were negative by CFT but 7 (12.1%) and 4 (6.8%) were positive by dot enzyme immunoassay and Western blots, respectively. The serological evidence of M. mycoides subsp. mycoides SC in camels and its likely implication in the epidemiology of CBPP are discussed.

The ovarian follicular wave pattern and induction of ovulation in the mated and non-mated one-humped camel (Camelus dromedarius).

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.

Patterns of hormone secretion throughout pregnancy in the one-humped camel (Camelus dromedarius).

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.