Selenium status and supplementation in dromedary camels

The Arabian camel (Camelus dromedarius) is well suited to the desert environment due to its remarkable physiological and metabolic adaptation. Nutrients requirements of the camel are not well defined, particularly that of trace elements. Selenium supplementation is often recommended to treat conditions attributed to Se deficiency such as cardiomyopathy. This paper reports the results of four experiments carried out using pregnant, non-pregnant, young and adult female camels. The commercial source of Se (i.e. sodium selenite) was used to provide supplementary levels between 0 to 16 mg of Se/day. The concentration of Se in serum and the activity of erythrocytes glutathione peroxidase (GSH-Px) were measured. The Se concentration in serum of camels increased linearly with increased Se supplementation levels from 0 to 4 mg/day, then plateau when levels further increased to a maximum of 16 mg/day. The average Se concentration (expressed as ng/ml) ranged between 100 and 500. Similar trend was observed for the GSH-Px activity. The results suggest a maximum tolerable dose of 8 mg/day and the recommended dose between 2 and 4 mg/day. (Résumé d'auteur

Maternal transfer of selenium by blood and milk in camels

Ten pregnant female camels were divided into two groups. The control group received no supplement; the experimental (treated) group received a daily oral supplement of 2 mg Se as selenite for the last three months of pregnancy and the first month of lactation. The Se concentration in serum increased significantly in the supplemented group and was threefold higher (305.9 ± 103.3 ng/mL) than in the concentration control group (109.3 ± 33.1 ng/mL). Blood values in camel calves were similar to those of the dams. The selenium concentration increased in similar proportions in milk (167.1 ± 97.3 ng/mL vs 86.4 ± 39.1 ng/mL in the supplemented and control groups respectively). In the colostrum, Se concentration was higher in both groups, but with a similar difference: 108.2 ± 43.9 ng/mL vs 302 ± 94.60. Significant correlations were reported between dam serum Se, camel calf serum Se, milk Se and GSH-Px both in dams and calves. (Résumé d'auteur

Facteurs de variation de quelques éléments race (sélénium, cuivre, zinc) et d'enzymes témoins de la souffance musculaire dans le sérum du dromadaire (Camelus dromedarius) aux Emirats arabes unis

Les effets de l'âge, du sexe, de la race et du statut physiologique sur le sélénium, le cuivre, le zinc, la créatine-kinase (CPK), l'alanine aminotransférase (ALT) et I'aspartate aminotransférase ont été étudiés chez le dromadaire (Camelus dromedarius). Au total, 240 animaux, jugés en bonne santé, parmi lesquels 166 de race locale, 68 croisée et 6 soudanaise, ont été choisis aléatoirement au sein d'une population de dromadaires provenant d'un seul troupeau. Ces dromadaires ont été classés en trois groupes d'âge: 2-4 ans, 5-7 ans, et 8 ans et plus. Les animaux ont été alimentés de luzerne, d'un mélange homogénéisé de lentilles, de dates et de soja, et d'un concentré. L'étude n'a indiqué aucun effet de la race sur les paramètres mesurés. Les faibles concentrations en zinc mesurées semblaient être dues à sa faible teneur dans les aliments supplémentés. Des corrélations significatives ont été obtenues entre le sélénium et le cuivre (0,292; p < 0,01), et entre le sélénium et le zinc (- 0,283; p < 0,01). Le sexe a montré une influence remarquable à l'exception de I'ALT. Le statut physiologique a affecté toutes les variables mais pas le CPK. L'intégration de ces éléments et la définition de leurs rôles précis chez les dromadaires de course sont d'une importance cruciale. (Résumé d'auteur

Animals that produce dairy foods: Camel

Camels are known for their ability to produce milk, in comparison to other species of Camelidae. Milk production from camels is mainly practiced in pastoral migratory systems but the intensive camel dairy farming is increasing in many countries. Dairy camels can be classified into three groups, high, medium, and low, based on their milk production. Only the high and medium milk-producing camels can be considered as true dairy camel types. Lactation length varies from 6 to 18 months. Infection by bacterial or mycotic pathogens is the main cause of mastitis. Socioeconomic constraints, longer calving interval, and hand milking hinder progress in improving milk production. Camel milk production from intensive systems has started to become a reality, and has shown promising results. The peak of lactation in camels tends to decline more steeply than in dairy cows; nevertheless, camels are much better providers of high-quality protein than cows, sheep, and goats to the people living in the arid and semiarid areas. The gross composition of camel milk is similar to that of cattle and goat milk but high differences were described in the fine composition (fatty acids, vitamins, type of proteins). Camel milk is generally opaque white and low in carotene. It has a sweet and sharp taste, but sometimes can also be salty. Most of the camel milk is consumed as fresh milk. However, surplus milk is processed into naturally fermented products. (Résumé d'auteur

Meta-analysis of the interactions between selenium status and haematological, biochemical and mineral parameters in camel blood

From several experiments on selenium metabolism in order to measure the effect of selenium supplementation (0, 2, 4, 8, 12 and 16 mg daily under selenite form), haematological, biochemical and mineral parameters were studied and their interactions with selenium status and dietary selenium were analyzed. Considering the increasing level of supplementation, important changes in blood parameters were observed: significant decreasing of PVC, haemoglobin and iron concentration attesting the sign of anaemia from 8 mg level. An important decrease of blood albumin and a drastic fall of uraemia expressed the loss of appetite in intoxicated animals receiving at least 12 mg selenium daily. At reverse, the enzymes attesting cell damage increased significantly. The decreasing of zinc and the increasing of copper from 8 mg showed inflammation process in target organs. It was concluded that se selenium supplementation could not overpass 4-8 mg per day for adult animals or 0.5-1 ppm in the diet. (Résumé d'auteur

Maternal transfer of selenium by blood and milk in camel

Ten pregnant female camels divided into two groups received after a 2 weeks adaptation period, an oral selenium (Se) supplementation (0 and 2 mg respectively) under sodium selenite form for 6 months from the three last months of gestation up to the three first months of lactation. Feed intake was assessed daily. Blood samples and body weight were taken on a bi-weekly basis, both in dams and their camel calves after parturition. Milk was collected at birth (colostrum), then on a bi-weekly basis. The Se concentration in serum increased significantly in the supplemented group and was threefold higher than the concentration compared to the control group, respectively 305.9 ± 103.3 ng/mL and 109.3 ± 33.1 ng/mL. Blood values in camel calves were similar to those of the dams. In calves, Se values were 106.3 ± 26.5 and 273.2 ± 48.0 ng/mL in the control and treated groups respectively. The selenium concentration increased in similar proportion in milk (86.4 ± 39.1 ng/mL in the control group vs 167.1 ± 97.3 ng/mL in treated group). In the colostrum, Se concentration was higher in the both groups, but with similar difference: it was threefold higher in treated group with a mean value 302 ± 94.60 vs 108.2 ± 43.9 ng/mL. The gluthathione-peroxidase (GSH-Px) activity in dams varied between 18.1 ± 8.7 in control group and 47.5 ± 25.6 IU/g Hb in treated group but decreased after parturition in both groups. At parturition, the camel calves born from supplemented dams had GSH-Px values threefold higher than the control calves: 73.8 ± 2.9 vs 25.0 ± 3.2 IU/g Hb (P<0.001). Vitamin E did not change significantly and was on average 1.17 ± 0.72 ng/mL and 1.14 ± 0.89 ng/mL in the control and treated group respectively. The mean value for camel calves in the control group was 0.65 ± 0.49 vs 0.82 ± 1.08 ng/mL in the treated one. Significant correlations were reported between mother serum Se, camel calf serum Se, milk Se and GSH-Px both in dams and calves. The results confirm the sensitivity of camel to Se supplementation with an important increase of selenium in serum and milk, allowing protection of camel calf against Se deficiency, commonly observed in Emirates. (Texte intégral

Effect of selenium supplementation on blood status and milk, urine, and fecal excretion in pregnant and lactating camel

Ten pregnant female camels divided into two groups received, after a 2-week adaptation period, an oral selenium (Se) supplementation (0 and 2 mg, respectively) under sodium selenite form for 6 months from the three last months of gestation up to the three first months of lactation. Feed intake was assessed daily. Blood samples and body weight were taken on a biweekly basis, both in dams and their camel calves after parturition. Feces and urine samples were collected monthly and milk on a biweekly basis. The Se concentration in serum increased significantly in the supplemented group and was threefold higher than the concentration compared to the control group, respectively, 305.9±103.3 and 109.3±33.1 ng/mL. The selenium concentration increased in similar proportion in milk (86.4±39.1 ng/mL in the control group vs 167.1±97.3 ng/mL in treated group), in urine, and feces. The gluthathionc peroxidase (GSH-Px) activity varied between 18.1±8.7 IU/g hemoglobin (Hb) in control group and 47.5±25.6 IU/g Hb in treated group but decreased after parturition in both groups. Vitamin E did not change significantly and was, on average, 1.17±0.72 and 1.14±0.89 ng/mL in the control and treated groups, respectively. Significant correlations were reported between serum Se, milk Se, GSH-Px, and fecal and urinary excretion or concentration. Blood values in camel calves were similar to those of the dams. The results seemed to confirm the sensitivity of camel to Se supplementation with an important increase of selenium in scrum and milk. (Résumé d'auteur

Artificial Forest Ecosystems of the UAE Are Hot Spots for Plant Species

Abstract: Desert and artificial forest ecosystems are important components of the UAE Environment. Additionally, these ecosystems sustain a large number of livestock and wildlife populations. An artificial forest was selected to study some attributes of plant communities. The forest had an area grazed by Arabian Oryx, where the rest was protected from grazing. Soils data showed that soil samples from areas dominated by Acacia tortillis and Prosopis cineraria had the highest levels of Organic Matter (0.78 % and 0.75%, respectively) (not a suitable place to put soil analysis here). While soil samples from areas dominated by Ziziphus species recorded the lowest rate of Organic Matter (0.36%). In general terms, grazing resulted in a significant deterioration in species diversity. Shannon-Wiener index value in the protected area (0.67) was greater than in the grazed area (0.46) by 45%. For the chemical analyses and gas production data obtained from the three sampling periods, only four out of the total number of plants has showed high nutritive values. Key words: Biodiversity camel desert UA

Chronic selenosis in camels

Three groups of 4 female camels, 2 years-old receiving a basal diet of Rhodes grass and concentrate were supplemented for 90 days with 8, 12 and 16 mg non-organic selenium to each group, respectively. Blood, faeces and urine were collected for selenium, glutathione peroxidase and vitamin E determination. Two camels per group were sacrificed at day 45 and 90. Organs and hair samples were used for histopathological findings and selenium content estimation. The selenium concentration increased significantly in 3 groups with an average value of 321.23 ± 140.5 ng/ml, 443.18 ± 231.06 ng/ml and 298.04 ± 212.13 ng/ml, respectively. Glutathione peroxidase activity varied between 26.85 and 174.16 IU/g Hb. Significant correlations between serum selenium, GSH-Px activity, urine and faecal Se were reported. No significant variation occurred for vitamin E (mean: 0.68 ± 0.36 ng/ml). High selenium level was observed in liver followed by kidney, spleen, lung, heart, pancreas, brain and ovary. Selenium concentration rose significantly in hair. Several symptoms related to selenosis have been reported and histopathological findings showed remarkable lesions in all the organs