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Afin d’évaluer la diversité phénotypique caméline en Mauritanie, des mensurations corporelles ont été réalisées sur 131 chamelles adultes amenées à l’abattoir de Nouakchott, animaux en provenance de l’ensemble du territoire mauritanien. En moyenne les mensurations corporelles ont été (en cm) de 51,5 ± 2,0 (longueur de la tête), 21,5 ± 1,5 (largeur de la tête), 108,4 ± 6,6 (longueur du cou), 65,6 ± 4,9 (tour du cou), 184,7 ± 8,1 (hauteur au garrot), 197,8 ± 8,2 (tour de poitrine), 147,1 ± 9,3 (longueur du corps) et 76,8 ± 5,2 (tour de cuisse). Par classification automatique, il a été possible d’identifier cinq phénotypes allant des animaux de petite taille, au petit gabarit et au cou fin et court, à des animaux longilignes de grande taille en passant par des gabarits de taille moyenne se distinguant par la grosseur de la tête ou des membres. Comparés aux données de la littérature, ces phénotypes apparaissent très proches des races décrites dans les pays du Maghreb et plus globalement des races africaines, et s’opposent aux races asiatiques, plus grandes et plus productives. La variabilité des phénotypes mauritaniens s’est avérée de faible ampleur, ce qui peut s’expliquer par la position de la Mauritanie, à l’extrémité occidentale de l’aire de répartition du dromadaire en Afrique, zone de brassage génétique important avec de faibles divergences rendues possibles par la topographie du pays.

International audience; On parle beaucoup des camélidés actuellement dans les médias. Tout d'abord car le dromadaire est à la source de l'épidémie de MERS-CoV de 2012 mais aussi en raison d'une particularité de leurs anticorps, qui ouvre des perspectives fascinantes pour la prise en charge de multiples pathologies, y compris la Covid-19.

The milk productivity improvement of she-camels requires a good feeding program that should indicate appropriate foods, required quantities, and how and when to distribute them. The aim of this study was to explore the interactions between milk productivity and body variations of dairy camels in response to experimental dietary treatments. The camels received a new diet every 15 days approximately, with higher rate of concentrates and high energy concentration. Results showed that diets with high energy or protein density, UFL (forage unit for milk production), and nutrient waste stimulated the development of body weight at the expense of milk production (p

International audience; Surra, caused by Trypanosoma evansi, is a re-emerging animal trypanosomosis, which is of special concern for camel-rearing regions of Africa and Asia. Surra decreases milk yield, lessens animal body condition score and reduces market value of exported animals resulting in substantial economic losses. A cross-sectional seroprevalence study of dromedary camels was conducted in Algeria, and major risk factors associated with infection were identified by collecting data on animal characteristics and herd management practices. The seroprevalence of T. evansi infection was determined in sera of 865 camels from 82 herds located in eastern Algeria using an antibody test (card agglutination test for Trypanosomiasis - CATT/T. evansi). Individual and herd seroprevalence were 49.5% and 73.2%, respectively, indicating substantial exposure of camels to T. evansi in the four districts studied. Five significant risk factors for T. evansi hemoparasite infection were identified: geographical area, herd size, husbandry system, accessibility to natural water sources and type of watering. There was no association between breed, sex or age with T. evansi infection. Results of this study provide baseline information that will be useful for launching control programmes in the region and potentially elsewhere.

Domestication begins with the selection of animals showing less fear of humans. In most domesticates, selection signals for tameness have been superimposed by intensive breeding for economical or other desirable traits. Old World camels, conversely, have maintained high genetic variation and lack secondary bottlenecks associated with breed development. By re-sequencing multiple genomes from dromedaries, Bactrian camels, and their endangered wild relatives, here we show that positive selection for candidate genes underlying traits collectively referred to as ‘domestication syndrome’ is consistent with neural crest deficiencies and altered thyroid hormone-based signaling. Comparing our results with other domestic species, we postulate that the core set of domestication genes is considerably smaller than the pan-domestication set – and overlapping genes are likely a result of chance and redundancy. These results, along with the extensive genomic resources provided, are an important contribution to understanding the evolutionary history of camels and the genomic features of their domestication., Robert R. Fitak et al. investigate the genetic basis for domestication in camels. They found that the positive selection of candidate domestication genes is consistent with neural crest deficiencies and altered thyroid hormone-based signaling. Their work provides insights to the evolutionary history of camels and genetics of domestication.

At world level, the current official number of large camelids cannot be determined exactly (it is estimated to be more than 35 million heads), and the role of camels in the livestock economy is highly variable. The only reliable statistics are provided by FAO since 1961. According to these data, five different patterns of demographic changes have been observed. In countries marked by a regular or drastic decline of their camelid population, a tendency to re-increase has been in force since the beginning of the century, except in India. Generally, countries marked by a sharp recent increase in their large camelid population have implemented a census and readjusted their data. Many inconsistencies occur in available data, most notably cases arising from changes occurring in state status (for example secession of Eritrea, Soviet Union collapse). Moreover, large camelid stocks in Australia, in countries of new camel establishment (Western countries) and those related to the expansion of camel farming, notably in Africa, are not recorded in the international database. In addition, there is no distinction between dromedary and Bactrian data. The present large camelid population in the world is probably more than 40 million and could reach 60 million after 25 years from now if the current demographic trend is maintained.

International audience; Chlamydiosis is caused by an obligate intracellular gram-negative bacterium of the genus Chlamydophila which is a zoonotic pathogen. The objectives of the study were to identify the seroprevalence of antibodies against Chlamydophila abortus in dromedary camel herds from four districts in eastern Algeria, as well as to estimate the association between seroprevalence and certain factors present at the animal and herd levels. Blood samples were collected from a random sample of animals within each of 82 camel herds. Serum samples were subjected to a C. abortus ELISA test, and association between the presence of antibodies and potential risk factors was estimated. Animal and herd seroprevalence were 2.5 % and 15.8 %, respectively, indicating substantial exposure of camels to C. abortus in the four districts studied. Age, breed, and sex did not influence seroprevalence in tested animals. Based on the univariate analysis, contact with sheep and goats, contact with other camel herds, and histories of abortion were major risk factors for infection. By using multivariate analysis, contact of camels with sheep and goats and with others camel herds, through shared grazing or watering points, were important factors for transmission of chlamydiosis with an odds ratio of 3.3 and 9.4, respectively. At the herd level the introduction of purchased animals was the major risk factor. This baseline information will be highly useful for launching C. abortus control programs in the region and potentially elsewhere.

The Camelidae family comprises the Bactrian camel (Camelus bactrianus), the dromedary camel (Camelus dromedarius), and four species of South American camelids: llama (Lama glama), alpaca (Lama pacos) guanaco (Lama guanicoe), and vicuña (Vicugna vicugna). The main characteristic of these species is their ability to cope with either hard climatic conditions like those found in arid regions (Bactrian and dromedary camels) or high-altitude landscapes like those found in South America (South American camelids). Because of such interesting physiological and adaptive traits, the interest for these animals as livestock species has increased considerably over the last years. In general, the main animal products obtained from these animals are meat, milk, and hair fiber, although they are also used for races and work among other activities. In the near future, climate change will likely decrease agricultural areas for animal production worldwide, particularly in the tropics and subtropics where competition with crops for human consumption is a major problem already. In such conditions, extensive animal production could be limited in some extent to semi-arid rangelands, subjected to periodical draughts and erratic patterns of rainfall, severely affecting conventional livestock production, namely cattle and sheep. In the tropics and subtropics, camelids may become an important protein source for humans. This article aims to review some of the recent literature about the meat, milk, and hair fiber production in the six existing camelid species highlighting their benefits and drawbacks, overall contributing to the development of camelid production in the framework of food security info:eu-repo/semantics/acceptedVersion

Genetic recombination is often demonstrated in coronaviruses and can result in host range expansion or alteration in tissue tropism. Here, we showed interspecies events of recombination of an endemic dromedary camel coronavirus, HKU23, with other clade A betacoronaviruses. Our results supported the possibility that the zoonotic pathogen MERS-CoV, which also cocirculates in the same camel species, may have undergone similar recombination events facilitating its emergence or may do so in its future evolution., Genetic recombination has frequently been observed in coronaviruses. Here, we sequenced multiple complete genomes of dromedary camel coronavirus HKU23 (DcCoV-HKU23) from Nigeria, Morocco, and Ethiopia and identified several genomic positions indicative of cross-species virus recombination events among other betacoronaviruses of the subgenus Embecovirus (clade A beta-CoVs). Recombinant fragments of a rabbit coronavirus (RbCoV-HKU14) were identified at the hemagglutinin esterase gene position. Homolog fragments of a rodent CoV were also observed at 8.9-kDa open reading frame 4a at the 3′ end of the spike gene. The patterns of recombination differed geographically across the African region, highlighting a mosaic structure of DcCoV-HKU23 genomes circulating in dromedaries. Our results highlighted active recombination of coronaviruses circulating in dromedaries and are also relevant to the emergence and evolution of other betacoronaviruses, including Middle East respiratory syndrome coronavirus (MERS-CoV). IMPORTANCE Genetic recombination is often demonstrated in coronaviruses and can result in host range expansion or alteration in tissue tropism. Here, we showed interspecies events of recombination of an endemic dromedary camel coronavirus, HKU23, with other clade A betacoronaviruses. Our results supported the possibility that the zoonotic pathogen MERS-CoV, which also cocirculates in the same camel species, may have undergone similar recombination events facilitating its emergence or may do so in its future evolution.

Slaughter stress responses were evaluated in the dromedary camel by analyzing hematocrit (Hct), neutrophil/lymphocyte ratio (NLR), hemolysis (H%), catalase activity (CATa) and plasma levels of cortisol (COR), triiodothyronine (T3), thyroxine (T4), glucose and malondialdehyde (MDA). Blood was collected during three different steps: at the arrival of the animals at the slaughterhouse just after unloading (step 1), at the end of a rest period of 16 to 20 hours (step 2) and finally during bleeding (step 3) after exposure to traditional slaughter stress. NLR, H%, MDA, glucose, COR, T3 and T4 measured at step 2 were significantly (P

Dromedaries are capable of digesting plant cell wall with high content of lignocellulose of poor digestibility. Consequently, their intestinal microbiota can be a source of novel carbohydrate-active enzymes (CAZymes). To the best of our knowledge, no data are available describing the biochemical analysis of enzymes in dromedary intestinal microbiota. To investigate new hydrolytic enzymes from the dromedary gut, a fosmid library was constructed using metagenomic DNA from feces of non-domestic adult dromedary camels living in the Tunisian desert. High-throughput functional screening of 13756 clones resulted in 47 hit clones active on a panel of various chromogenic and non-chromogenic glycan substrates. Two of them, harboring multiple activities, were retained for further analysis. Clone 26H3 displayed activity on AZO-CM-cellulose, AZCL Carob galactomannan and Tween 20, while clone 36A23 was active on AZCL carob galactomannan and AZCL barley β-glucan. The functional annotation of their sequences highlighted original metagenomic loci originating from bacteria of the Bacteroidetes/Chlorobi group, involved in the metabolization of mannosides and β-glucans thanks to a complete battery of endo- and exo-acting glycoside hydrolases, esterases, phosphorylases and transporters.

Significance Middle East respiratory syndrome (MERS) is a zoonotic disease of global health concern, and dromedary camels are the source of human infection. Although Africa has the largest number of dromedary camels, and MERS-coronavirus (MERS-CoV) is endemic in these camels, locally acquired zoonotic MERS is not reported from Africa. However, little is known of the genetic or phenotypic characterization of MERS-CoV from Africa. In this study we characterize MERS-CoV from Burkina Faso, Nigeria, Morocco, and Ethiopia. We demonstrate viral genetic and phenotypic differences in viruses from West Africa, which may be relevant to differences in zoonotic potential, highlighting the need for studies of MERS-CoV at the animal–human interface., Middle East respiratory syndrome coronavirus (MERS-CoV) causes a zoonotic respiratory disease of global public health concern, and dromedary camels are the only proven source of zoonotic infection. Although MERS-CoV infection is ubiquitous in dromedaries across Africa as well as in the Arabian Peninsula, zoonotic disease appears confined to the Arabian Peninsula. MERS-CoVs from Africa have hitherto been poorly studied. We genetically and phenotypically characterized MERS-CoV from dromedaries sampled in Morocco, Burkina Faso, Nigeria, and Ethiopia. Viruses from Africa (clade C) are phylogenetically distinct from contemporary viruses from the Arabian Peninsula (clades A and B) but remain antigenically similar in microneutralization tests. Viruses from West (Nigeria, Burkina Faso) and North (Morocco) Africa form a subclade, C1, that shares clade-defining genetic signatures including deletions in the accessory gene ORF4b. Compared with human and camel MERS-CoV from Saudi Arabia, virus isolates from Burkina Faso (BF785) and Nigeria (Nig1657) had lower virus replication competence in Calu-3 cells and in ex vivo cultures of human bronchus and lung. BF785 replicated to lower titer in lungs of human DPP4-transduced mice. A reverse genetics-derived recombinant MERS-CoV (EMC) lacking ORF4b elicited higher type I and III IFN responses than the isogenic EMC virus in Calu-3 cells. However, ORF4b deletions may not be the major determinant of the reduced replication competence of BF785 and Nig1657. Genetic and phenotypic differences in West African viruses may be relevant to zoonotic potential. There is an urgent need for studies of MERS-CoV at the animal–human interface.

The intensity of stress depends on several external factors, such as distance and conditions of transport, climate change, the nature of the journey and the vehicle used, etc... Our research aims to study the effect of loading density on certain physiological, hematological, biochemical and hormonal parameters in camels. Sixteen male animals belonging to the municipal slaughterhouse of Casablanca (west of Morocco) were divided into two groups of 8 camels to study the effect of 2 loading densities: 1camel/2-3.6m2 (Group I) and 1camel/1.44-1.80m2 (Group II). Hct, NLR, H% and biochemical parameters were analyzed in our laboratory (LPGM) at the Ben M'Sik Faculty of Sciences in Casablanca, while the hormones were analyzed by radioimmunology at the National Center of Energy, Sciences and Nuclear Techniques of Maâmoura, Morocco. In Groups I and II, rectal temperature, heart and respiratory rates, hemolysis, neutrophil/lymphocyte ratio and plasma levels of Glu, COR, T3 and T4 showed a significant increase (P

International audience; The effect of vacuum level and pulsation rate on machine milking efficiency in lactating dromedary camels were studied in 2 separate experiments. In the first experiment, a total of 14 multiparous camels in early (n=7) and late (n=7) lactation were used to study the effects of vacuum level (45 and 50 kPa) and pulsation rate (52 and 60 pulsations/min) on milk fractionation and flows traits. At the morning milking, volumes of machine milk (MM), machine stripping milk (MSM) and residual milk (RM) were recorded at two different days. For the second experiment, another 10 multiparous dromedary camels at mid stage of lactation were used to evaluate teat condition and udder health during 10 weeks. Milk samples were collected weekly at each milking and analysed for major milk constitutes and udder health. The 50 kPa vacuum level and 60 pulsations/min decreased (P

Middle East respiratory syndrome coronavirus (MERS-CoV) is an existential threat to global public health. The virus has been repeatedly detected in dromedary camels (Camelus dromedarius). Adult animals in many countries in the Middle East as well as in North and East Africa showed high (>90%) seroprevalence to the virus. Middle East respiratory syndrome coronavirus isolated from dromedaries is genetically and phenotypically similar to viruses from humans. We summarize current understanding of the ecology of MERS-CoV in animals and transmission at the animal–human interface. We review aspects of husbandry, animal movements and trade and the use and consumption of camel dairy and meat products in the Middle East that may be relevant to the epidemiology of MERS. We also highlight the gaps in understanding the transmission of this virus in animals and from animals to humans.

Dromedary (Camelus dromedarius) and Bactrian (Camelus bactrianus) camels are close species and their hybrids fertile, but until now no comparative data on the nutrient composition of their meat has been available. Six muscle samples were collected from nine Bactrians and 10 dromedaries from Kazakhstan and the Sultanate of Oman, respectively. They were used for amino-acid pattern determination. The essential amino-acid index was higher for all muscles in the dromedary meat than in Bactrian meat with a mean value of 216.9 and 191.6, respectively, which is high compared to other red meats. The between-muscle variability was higher in dromedary than in Bactrian meat and was more important than the between-species variability. However, the two species were well discriminated on the second factor of the linear factorial discriminant analysis with 93.14% well-classed meat based on 7 discriminant amino-acid including 4 essential ones. The Bactrian camel meat was richer in proline and leucine and the dromedary camel meat in serine, tyrosine, histidine, threonine and arginine. In spite of these differences, both meats were characterized by their richness in methionine and leucine. Consequently, the dromedary and Bactrian meats could provide an excellent source of high-quality proteins for human consumers.

Body weight, testes development and serum testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels were determined and compared in two groups of peri-pubertal male dromedaries. Daily maximum and minimum ambient temperatures and dry and wet-bulb temperatures were recorded. Temperature-humidity index was calculated. The camels were divided into two equal groups of nine camels each, of comparable body weight: Group (A) received a diet of 13% crude protein and 2.9 MCal metabolizable energy (ME) with added premix, while Group (B) received a non-pelleted diet of alfa-alfa and wheat straw at the ratio of 1:3 giving 12.4% CP and 2.7 MCal ME. Individual feed intake was calculated after 14 days of adaptation. Feed offered and orts were recorded daily throughout the experimental period (24 months). Animals were fed diets containing 1:3 alfa alfa:wheat straw. Blood samples were collected from 5 camels in each group at 15-day intervals during the experimental period. None significant difference in total body weight was found between groups A and B throughout the entire experimental period (p >0.05). Group averages of daily feed intake for the entire period were 5.82 kg in group A and 7.08 kg in group B, respectively (p

To the Editor: Middle East respiratory syndrome coronavirus (MERS-CoV) acquired from animals causes severe pneumonia in humans, with some chains of human-to-human transmission, leading to large outbreaks. MERS-CoV is a cause of concern for global public health. The only natural host of MERS-CoV identified so far is the dromedary camel (Camel dromedarius) (1,2), and transmission from camels to humans has been documented (3). The geographic distribution of MERS-CoV in dromedaries extends beyond the Arabian Peninsula (where human cases have been reported) to North and East Africa (where human cases have not been reported) (2,4). However, MERS-CoV from a camel in Egypt and MERS-CoV from a human were phenotypically similar in tropism and replication competence in ex vivo cultures of the human respiratory tract (5). Our previous study demonstrated no evidence of MERS-CoV infection in Bactrian camels in Mongolia (6). The question whether MERS-CoV is endemic in camelids in Central Asia remains unanswered. MERS-CoV RNA was detected in swab samples from camels in Iran, which had been imported from Pakistan; however, where the infection was acquired is unclear (7). In Asia, Kazakhstan is of particular interest because large populations of 2 major camelid species overlap: 90% Bactrian (Kazakh breed including 3 ecotypes) and ≈10% dromedary (Arvana breed from Turkmenistan) and their hybrids (8). To determine whether MERS-CoV is present in camelids in Kazakhstan, we conducted a seroepidemiologic survey. During February–March 2015, blood was collected from 550 female camels (455 dromedary, 95 Bactrian) (Figure) in 2 regions, Almaty and Shymkent, which differ in camelid density (0.034 and 0.20 camels/km2, respectively; http://www.stat.gov.kz). Dromedaries were sampled in the cities/villages of Kyzylorda (105 animals from 2 herds), Zanakorgan (35 animals from 1 herd), Sholakkorgan (110 animals from 2 herds), and Akshiy (205 animals from 4 herds). Bactrian camels were sampled in Sholakkorgan (40 animals from 1 herd) and Kanshengel (55 animals from 1 herd) (Figure). For dromedary camels, mean age was 6.1 years (SD 3–7 years) and mean herd size was 53.6 animals (SD 31–70); for Bactrian camels, mean age was 6.5 years (SD 5–8 years) and mean herd size was 48.6 animals (SD 40–55). Serum samples were tested for MERS-CoV antibodies at a screening dilution of 1:20 by using a validated MERS-CoV (strain EMC) spike pseudoparticle neutralization test (9). Positive and negative controls were included in each run. Absence of positivity for any sample indicated a lack of recent or past MERS-CoV infection. Figure Density of camelids in Kazakhstan (extracted from the Ministry of National Economy of the Republic of Kazakhstan Committee on Statistics, Department of Statistics; http://www.stat.gov.kz) and specimen collection for detection of Middle East respiratory ... Two randomly selected samples each from dromedaries from Kyzlorda, Zanakorgan, and Akshiy and Bactrians from Sholakkorgan and Kanshenegel were tested for neutralizing antibody to bovine coronavirus (9). All 10 samples were seropositive, as has been reported for Bactrian camels in Mongolia and the Middle East (6,9). Given the uniformly high seroprevalence of MERS-CoV infection among dromedaries in Africa and the Arabian Peninsula, the lack of infection in dromedaries in southern Kazakhstan was surprising. Because genetically diverse MERS-CoV from Africa remains antigenically conserved with viruses from the Arabian Peninsula, the lack of antibodies is probably not explained by antigenically divergent strains (9). Feral dromedaries in Australia, which originated from animals imported from Afghanistan or Pakistan during 1840–1907, are also seronegative for MERS-CoV (10). In contrast, bovine-like coronavirus seems to be present in dromedaries everywhere (including Kazakhstan and Australia). Our study was limited by sample size and by geographic coverage. Of the ≈180,000 camels in Kazakhstan, we studied camelids from only 2 of the 13 provinces. No samples were collected from the western part of the country near Turkmenistan, where dromedaries are also common. Dromedaries are clearly a natural host of MERS-CoV. However, the finding that MERS-CoV is not endemic in dromedaries in all geographic regions suggests the possibility that dromedaries may not be the ultimate natural reservoir (i.e., the long-term host of a pathogen of an infectious disease). Topography (i.e., mountain chains) may limit camel movements from the Middle East or Africa to Central Asia, although such interchange certainly occurred centuries ago as a consequence of the silk-trade routes through southern Kazakhstan. The only known recent imports to Kazakhstan are dromedaries (Arvana breed), brought from Turkmenistan for cross-breeding with Bactrians to improve milk production (8). The findings that MERS-CoV is not universally endemic in dromedaries raises the hypothesis that certain species of bats or some other animal, the environment, or both, may constitute a maintenance community and be the true natural reservoir of MERS-CoV and that the virus spills over to camels and is maintained within camels for varying periods of time. Further studies on the epidemiology of MERS-CoV infection among camelids from central Asia are warranted.

Summary Middle East respiratory syndrome coronavirus (MERS‐CoV) cases without documented contact with another human MERS‐CoV case make up 61% (517/853) of all reported cases. These primary cases are of particular interest for understanding the source(s) and route(s) of transmission and for designing long‐term disease control measures. Dromedary camels are the only animal species for which there is convincing evidence that it is a host species for MERS‐CoV and hence a potential source of human infections. However, only a small proportion of the primary cases have reported contact with camels. Other possible sources and vehicles of infection include food‐borne transmission through consumption of unpasteurized camel milk and raw meat, medicinal use of camel urine and zoonotic transmission from other species. There are critical knowledge gaps around this new disease which can only be closed through traditional field epidemiological investigations and studies designed to test hypothesis regarding sources of infection and risk factors for disease. Since the 1960s, there has been a radical change in dromedary camel farming practices in the Arabian Peninsula with an intensification of the production and a concentration of the production around cities. It is possible that the recent intensification of camel herding in the Arabian Peninsula has increased the virus' reproductive number and attack rate in camel herds while the ‘urbanization’ of camel herding increased the frequency of zoonotic ‘spillover’ infections from camels to humans. It is reasonable to assume, although difficult to measure, that the sensitivity of public health surveillance to detect previously unknown diseases is lower in East Africa than in Saudi Arabia and that sporadic human cases may have gone undetected there.

Résumé En 2012, une nouvelle maladie virale émergente est apparue au Moyen-Orient, le MERS, abréviation en anglais pour « Syndrome respiratoire du Moyen-Orient ». Au 9 janvier 2014, elle avait déjà touché 178 personnes dans le monde, dont 75 étaient décédées dans un tableau d’insuffisance respiratoire et de diarrhée. La nouvelle maladie ressemblait cliniquement au SRAS (2002–2003), de sinistre mémoire, et comme le SRAS, était provoquée par un Betacoronavirus nouveau. On a donc pensé que des chiroptères pouvaient être à l’origine du MERS. D’ailleurs, de nouvelles études ont montré qu’en Arabie Saoudite un exemplaire de la chauve-souris Taphozous perforatus hébergeait un segment de quelques nucléotides identique au segment homologue de la souche isolée du cas-index de l’épidémie. De plus, de nombreuses souches de Betacoronavirus, plus ou moins proches génétiquement de celles responsables du MERS chez l’Homme, ont été isolées de chauves-souris en Afrique, en Asie et en Europe. Mais, une autre hypothèse a été proposée simultanément incriminant le dromadaire (Camelus dromedarius L) comme acteur très vraisemblable dans la transmission de la maladie. Elle est basée sur des observations épidémiologiques et les résultats de plusieurs enquêtes sérologiques. Un bilan des autres zoonoses virales dans lesquelles le dromadaire est plus ou moins impliqué renforce cette hypothèse: le MERS-CoV, l’agent étiologique du nouveau syndrome, pourrait bien être véhiculé par cet animal.

Relationship between serum levels of cortisol at slaughter and changes of some parameters of meat was investigated in 50 male camels, during ageing for 10 days at 4±1°C. Blood was sampled at slaughter to determine serum levels of cortisol and oblique abdominal external muscle was collected after slaughter to analyze pH, electrical conductivity (EC), drip loss (DL), cooked loss (CL), moisture, solids, ashes, protein total, calcium (Ca), phosphorus (Pi), magnesium (Mg), sodium (Na), potassium (K), catalase activiry (CATa), malondialdehyde (MDA), shrinkage, R-value and total haem pigment (THP) at days 0 (four hours postmortem), 5 and 10 of refrigerated storage. The camels were divided into 3 groups (Gr) with different serum levels of cortisol at slaughter (low, high and very high levels): Gr1 (13.07-67.9 ng/mL, n= 24), Gr2 (80.29-107.21 ng/mL, n= 7) and Gr3 (133.7-198.04 ng/mL, n= 19). Compared to Gr1, Gr2 and Gr3 had a significant (P

The objectives of the present study were to monitor the microbiological quality and somatic cell count (SCC) of bulk tank milk at the world's first large-scale camel dairy farm for a 2-yr period, to compare the results of 2 methods for the enumeration of SCC, to evaluate correlation among milk quality indicators, and to determine the effect of specific factors (year, season, stage of lactation, and level of production) on milk quality indicators. The study was conducted from January 2008 to January 2010. Total viable count (TVC), coliform count (CC), California Mastitis Test (CMT) score, and SCC were determined from daily bulk milk samples. Somatic cell count was measured by using a direct microscopic method and with an automatic cell counter. In addition, production parameters [total daily milk production (TDM, kg), number of milking camels (NMC), average milk per camel (AMC, kg)] and stage of lactation (average postpartum days, PPD) were recorded for each test day. A strong correlation (r = 0.33) was found between the 2 methods for SCC enumeration; however, values derived using the microscopic method were higher. The geometric means of SCC and TVC were 394 × 103 cells/mL and 5,157 cfu/mL during the observation period, respectively. Somatic cell count was >500 × 103 cells/mL on 14.6% (106/725) and TVC was >10 × 103 cfu/mL on 4.0% (30/742) of the test days. Both milk quality indicators had a distinct seasonal pattern. For log SCC, the mean was lowest in summer and highest in autumn. The seasonal pattern of log TVC was slightly different, with the lowest values being recorded during the spring. The monthly mean TVC pattern showed a clear difference between years. Coliform count was

International audience; Modeling the lactation curve is an important step for assessing the true milk potential of dairy animals. The present study aims to investigate the use of four different mathematical models (Wood, Cobby and Le Du,Cappio-Borlinoand and Dhanoa) to describe camel milk lactation curves, to estimate the potential of dairy she-camels and to identify different factors that could influence produced milk quantity and quality of Maghrebi she-camel. A total of 813 records from one experimental farm were used. Data collections were daily made with three milking per day. The complete milking was performed on two quarters (one posterior and one anterior). The other two were reserved for the calf and the volume collected was doubled. Among the four used mathematical models, the Wood model appeared the most appropriate according to mean square prediction error (MSPE), coefficient of determination (R2 = 83.56). The differences in estimated total milk yields between the models were not statistically significant. All models were adequate in describing total milk yield, although total milk yield estimated using the Wood model was very close to total milk yield. The quantities of daily produced milk differed among individuals. Milk production peaked approximately at 3rd months postpartum and then decreased. Daily production was 6.72 +/- 2.46 L. Milk yield decreased with lactation. Daily milking order as well as stage of lactation affects milk yield and its composition. These constituents became concentrated as lactation proceeded, and protein was substituted by fat. Calving date had a similar concentrating effect on fat whereas it decreased protein. This study showed that among the population of camels in Tunisia, improving environment and management of camel can be a way to improve milk production.

This study determined the prevalence of fetal wastage due to slaughter of pregnant camels, and the relationship between fetal wastage and factors such as breed, season, abattoir location, and age. Pregnancy characteristics of indigenous camels were also investigated. Reproductive tracts were collected from 912 female camels at two abattoirs in southeast Algeria over 2.5 years. Before slaughter, data regarding reasons for culling were obtained. Pregnancy was detected in 21.7% of camels and was higher (P

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. (Resume d'auteur)

The present study aimed ta investigate the effect of nutrition on body weight gain, avaries development, blood components (total protein, alblllllen, globulin, cholesterol and glucose) and hormone level (estradiol and progesterone) in pre-pubertal she-camels. Fourteen dromedary she-camels (Camelus dromedarius) were divided in two groups CA and B) similar body weight and age ai the siart of the experiment (200 kg and 12 month, respectively). Group A received diet with 13% Crude Protein (CP) and 2.9 Meal Metabolisable Energy (ME). Group B received the traditional diet of the fann. Both diets contained 25:75 forage:concentrate. Individual feed intake was calculated after 14 days of adaptation period. Feed offered and arts was recorded daily during the whole experimental period of 12 months. Blood samples were taken from each group every 15 days throughout the experimental period. Estradiol, progesterone concentrations were measured using ELISA kits. Body weight and average daily gain for the Ist 6 months did not show significant differences between treatments. On the contrary for the last 6 months, treatment A significantly increased body weight and daily weight gain when compared to B (70.07±8.17 kg and 0.389±0.05 kg day-' vs. 37.86±8.17 kg and 0.210±O.05 kg day-l, respectively. Group A was more efficient converting feed to body weight comparing with group B. Feed Conversion Ratio (FCR) for the whole period was 11.25 and 13.74 for Group A and B, respectively. Group B had greater ovary size than Group A but the difference was not significant. Size of right ovary was smaller than the left one and season had positive effects on both right and left ovary sizes. Greater ovary sizes were observed in Winter and Spring comparing with Swnmer and Autumn. Group A had higher blood estradiollevel comparing with Group B while there was no difference between groups in progesterone levels. Il was concluded that feeding regirne did not affect body weight, daily body weight gain and blood progesterone levels but improved feed conversion ratio and blood estrogen levels. (Resume d'auteur)

Cryptosporidium is a ubiquitous enteropathogen protozoan infection affecting livestock worldwide. The present study was carried out to determine the prevalence of Cryptosporidium infection in different age groups of dromedary camels in northwestern Iran from November 2009 to July 2010. A total number of 170 fecal samples were collected and examined using modified Ziehl-Neelsen (MZN) staining under light microscope. Examination of stained fecal smears revealed that 17 camels (10%) were positive for Cryptosporidium-like. The prevalence of Cryptosporidium-like was significantly higher in camel calves (< 1 years old) (20%) than other age groups, in which the diarrhoeic calves had the prevalence of 16%. In adult camels the prevalence was 6.5%. There was no significant difference in the prevalence of Cryptosporidium-like between male and female camels. It is concluded that Cryptosporidium infection is a problem in camel husbandry and could be of public health concern in the region.

Au Kazakhstan, la cohabitation du chameau de Bactriane, du dromadaire et de leurs hybrides est un fait courant au sein même des fermes. La composition physico-chimique de 147 échantillons de lait provenant de 57 chameaux de Bactriane, 70 dromadaires et 20 hybrides a été déterminée. Les échantillons ont été prélevés dans 4 fermes provenant de 4 régions différentes aux 4 saisons au cours d'une année. Comparé à celui de dromadaire, le lait de chamelle de Bactriane apparaît plus riche en matière grasse (6,67 vs. 5,94 %), vitamine C (177 vs. 152 mgL-1), calcium (1,30 vs. 1,16 gL-1), et phosphore (1,07 vs. 0,91 gL-1). L'indice d'iode est significativement plus élevé dans le lait de dromadaire (16,69) que dans le lait de chamelle de Bactriane (14,99). Afin de distinguer les deux types de lait, une analyse discriminante a été mise en oeuvre après avoir éliminé les effets liés à la variabilité saisonnière et régionale. Les paramètres discriminants sont le phosphore (coefficient linéaire discriminant=–1,00), le pH(–0,408), la vitamine C (–0,377) et la matière grasse (–0,226), en concentrations plus élevées dans le lait de Bactriane que dans celui de dromadaire. L'indice d'iode (0,287) était plus élevé dans le lait de dromadaire. Après une analyse discriminante quadratique, on peut prédire d'après la composition du lait, l'origine spécifique avec un pourcentage de bien classés de 75,4 %. La composition chimique du lait des hybrides s'est avérée intermédiaire mais avec un faible pouvoir discriminant.

International audience; The welfare conditions of domestic animals during transport to the slaughterhouse are largely known able to influence the level of their stress, physiology and meat quality. Furthermore, the reaction of animals to stressors depends on the duration and intensity of these stressors. The objective of the study was to investigate the effect of transport distance on some blood physiological indicators of stress and biomarkers of oxidant stress in camels. Transport distances were categorized as short (72-80km), medium (160-170km) and long (350-360km) distance. Haematocrit, haemolysis, cortisol, glucose, lactate, malondialdehyde and catalase increased gradually and significantly (P

Myostatin (MSTN), a negative regulator of skeletal muscle development in mammals, represents a key target for genetic investigations in meat-producing animals, with mutations responsible for increased skeletal-muscle mass currently described in several livestock species. Dromedary camels play a major economic role as suppliers of meat for human consumption across several countries. Notwithstanding, a comprehensive characterization of the sequence variability at the Camelus dromedarius MSTN locus was still lacking. Here we present the first extensive sequence and polymorphism analysis of the MSTN gene in the Camelus dromedarius species. Out of more than 3.6 kb of nucleotide sequence screened on 22 animals from 3 different Northern African regions, only 3 variant sites in the first intron were detected. The low observed diversity may reflect the evolutionary history of the species, likely developed as domesticates from a low variable wild ancestor population. Sequence identity among Camelus dromedarius and other Cetartiodactyla highlighted a tree topology consistent with previous reports of a closer relationship between Tylopoda and Suiformes. A close similarity between C. ferus and Camelus dromedarius was observed within Tylopoda. A markedly higher sequence identity between Camelus dromedarius and the other vertebrate species was observed at the MSTN locus compared to other genes, thus confirming it as a highly conserved target across mammals.

Consumption of fermented camel milk, named shubat, is very popular in Central Asia and especially in Kazakhstan where it is known for its medicinal and dietary properties. To identify lactic acid bacteria (LAB) camel milk and shubat were sampled from 4 regions of Kazakhstan with important camel's population. In total, 26 dairy samples from 13 selected farms representing the variability of the farming system in the country were collected. Isolated strains were identified by genotypic approach including PCR using three different pairs of primers (338f/518r; W001/23S1; Lac1/Lac2/Lac3) and 16S rDNA gene sequencing. Three genus were in majority: Lactococcus, Lactobacillus and Enterococcus. The following microorganisms were identified: Enterococcus durans ; Enterococcus faecalis; Enterococcus faecium; Lactobacillus casei; Lactobacillus casei subsp. casei; Lactobacillus curvatus; Lactobacillus kefiri; Lactobacillus paracasei; Lactobacillus sakei; Lactococcus lactis subsp. lactis; Leuconostoc mesenteroides. Identification of camel milk and shubat microflora provides a theoretical foundation for developing starter cultures by using local LAB strains for industrial production of traditional fermented milk products. (Resume d'auteur)

In order to compare cholesterol contents in cow and camel milk in similar farming conditions, milk and blood of seven cows and seven camels maintained at normal diet at the middle of lactation were sampled at morning and evening, then after two weeks of keeping them at low protein diet. The cholesterol content in camel milk (5.64 ± 3.18 mg/100 g, SD) was not significantly lower than in cow milk (8.51 ± 9.07 mg/100 g, SD). Fat contents in cow milk were higher. Cholesterol/fat ratios were similar in the two species (camel: 225 ± 125 mg/100 g fat; cow: 211 ± 142 mg/100 g fat). The serum cholesterol concentration was significantly higher in cow (227.8 ± 60.5 mg/100 ml) than in camel (106.4 ± 28.9 mg/100 ml). There was a significant difference between morning and evening milking in milk fat compositions and concentrations in cholesterol. Fat levels increased in cow after two-week low energy-protein diet.

International audience; Hybrid camels, intentional crosses between dromedaries and bactrian camels, are prized for their robustness and endurance. They were the prime vehicles of short and long distance caravan trade in a large area between Greece and Mongolia until the whole-scale introduction of motorized transport. This paper proposes a model for the zooarchaeological study of camel hybridization as a culture-historical phenomenon based on ethnographic and ethnohistoric observations of camel wrestling. Camel wrestling spectacles involve large audiences who gather in large arenas to watch first generation male hybrid camels wrestle during the mating season. While Anatolia was chosen as a case region for testing the model, it can be applied to all regions where hybrids are expected to occur in the archaeological record.; Les chameaux hybrides, issus du croisement intentionnel du chameau de Bactriane et du dromadaire, sont prisés pour leur robustesse et leur endurance. Jusqu’à l’introduction des véhicules à moteur pour le transport de marchandises, les chameaux hybrides étaient les meilleurs moyens de transport pour les caravanes qui permettaient de commercer à courte et longue distance dans une vaste région allant de la Grèce à la Mongolie. Basé sur des observations ethnographiques et ethno-historiques des combats de chameaux, cet article propose un modèle pour l’étude archéozoologique de l’hybridation des chameaux en tant que phénomène culturel et historique. De nombreux spectateurs se rassemblent dans de grandes arènes pour assister aux combats de chameaux mâles hybrides de première génération pendant la période de rut. Le modèle proposé a été testé en Anatolie mais peut être appliqué à toutes les régions où des restes de chameaux hybrides figurent parmi le matériel archéologique.

International audience; The aims of the present study were to investigate the prevalence of ovarian hydrobursitis, and its pathologic and histopathologic characteristics in slaughtered female camels. The reproductive tracts of 740 female camels were collected and examined from January 2011 to February 2013, in two abattoirs from southeast Algeria. Ovarian hydrobursitis was observed in 32 reproductive tracts (4.32%); unilaterally (n=17) or bilaterally (n=15). The frequency of right side and left side ovarian hydrobursitis was not significantly different. It was associated with pen-uterine adhesion, pyometra, and paraovarian cysts. The affection was observed in some pregnant cases. Microscopic examination revealed diffuse edema, capillary congestion, infiltration, and heavy infiltration of mononuclear cellular, cystic dilatation of multi-acinal structures, desquamation and hyperplasia of the epithelial lining, tiny hemorrhages, and a large number of hemosiderin-laden macrophages. In conclusion, this study has identified the prevalence and the main anatomical and histopathological features the ovarian hydrobursitis. This. syndrome is a serious problem affecting the fertility in dromedary camel in Algeria.

Une enquête sur des dromadaires élevés en liberté dans les régions de Butana, Kassala et Blue Nile au Soudan a été effectuée entre 1992 et 1994 pour évaluer l'incidence de l'ecthyma contagieux du dromadaire (ECD). Trente-huit troupeaux étaient atteints de la maladie. D'un point de vue clinique, des lésions sont d'abord apparues sur les lèvres des animaux atteints sous forme de croûtes ou de croûtes fissurées. Tous les cas d'ECD concernaient les jeunes dromadaires jusqu'à 3 ans d'âge et, pour 97,8 % d'entre eux, ceux de moins d'un an. Les taux de morbidité et de mortalité moyens chez des jeunes de moins d'un an étaient respectivement de 60,2 et 8,8 % alors que la létalité moyenne était de 13 %. Cette maladie variait selon la saison, étant associée à la saison des pluies et à la consommation d'acacias épineux causant l'abrasion de la peau.

Une enquete sur l'epidemiologie de la trypanosomose cameline a T. evansi en Mauritanie a ete conduite sur 2 078 dromadaires de tous âges dans quatre regions (Trarza, Gorgol, Adrar, Hodh El Chargui) a caracteristiques climatiques et ecologiques differentes. La prevalence de l'infection a ete determinee par l'examen de frottis sanguins et par trois tests serologiques, le card agglutination test for trypanosomosis (CATT), l'immunofluorescence indirecte (IFI) pour la detection d'anticorps et l'enzyme-linked immunosorbent assay (ELISA) pour la detection d'antigenes. La prevalence globale de l'infection etait de 1,4 p. 100 a l'examen parasitologique. La seroprevalence etait de 16,5 p. 100 au CATT, de 24,3 p. 100 a l'IFI et de 14, 1 p. 100 a l'ELISA-Ag. La prevalence variait selon la region, la strategie de conduite d'elevage pratiquee par les eleveurs, les troupeaux et l'âge des animaux. Cette enquete a montre que la trypanosomose cameline etait presente en Mauritanie, surtout dans les zones boisees, pres des cours d'eau frequentes par les animaux. (Resume d'auteur)

Antioxidant vitamins may affect an organism’s capacity for defense against damage caused by reactive oxygen species (ROS), and biological markers of the dietary exposure to these compounds is of importance.The present study was designed to evaluatethe protective effect of vitamin E and vitamin C against the hemolysis induced by hydrogen peroxide (H2O2) in camel’s red blood cellsin vitro,and forassessing the vulnerability of camel erythrocytes to oxidative stress (OS). Vitamin E and vitamin C were able to protect thered blood cellsagainst theH2O2-induced hemolysis and thiobarbituric acid reactive species (TBARS) formation. The antioxidative property of these vitamins in reducing oxidative injury showed in this work, may suggest that these molecules may be very helpful to fight the ROS during OS induced by transportation, heat, deshydratation, aging, and parasite, infectious and metabolic diseases in dromedary camels.

A total of 22 dairy dromedary camels under intensive conditions in late lactation (275 ± 24 days) were used to study the relationship between external and internal udder morphology and machine milking performances. Measurements of udder and teat morphology were obtained immediately before milking and in duplicate. Individual milk yield, lag time and total milking time were recorded during milking, and milk samples were collected and analyzed for milk composition thereafter. Cisternal and alveolar milk volumes and composition were evaluated at 9 h milking interval. Results revealed that dairy camels had well developed udders and milk veins, with medium sized teats. On average, milk yield as well as milk fat and protein contents were 4.80 ± 0.50 L d-1, 2.61 ± 0.16% and 3.08 ± 0.05%, respectively. The low fat values observed indicated incomplete milk letdown during machine milking. Lag time, and total milking time were 3.0 ± 0.3, and 120.0 ± 8.9s, on average, respectively. Positive correlations (p < 0.05) were observed between milk yield and udder depth (r = 0.37), distance between teats (r = 0.57) and milk vein diameter (r = 0.28), while a negative correlation was found with udder height (r = -0.25, p < 0.05). Cisternal milk accounted for 11% of the total udder milk. Positive correlations were observed between total milk yield and volume of alveolar milk (r = 0.98; p < 0.001) as well as with volume of cisternal milk (r = 0.63, p < 0.05). Despite the low udder milk storage capacity observed in dairy camels, our study concluded that the evaluated dromedary sample had adequate udder morphology for machine milking. Finally, positive relationships were detected between milk yield and udder morphology traits of dairy camels.

Weekly milk records of 47 she-camels in a multibreed dairy camel herd were collected for over a period of 5 years. A total of 72 lactation curves were defined, and relationships with parity, calving season, lactation length, milk production level, following lactations, and dam weight were analyzed. Overall mean values were milk yield up to 12 months, 1,970 ± 790 l; lactation length, 12.5 months; persistency, 94.7 %; weekly peak yield, 50.7 l; monthly peak yield, 220 ± 90 l; and the number of weeks to reach peak yield, 28. The highest productivity was recorded in summer with a weekly mean of 48.2 ± 19.4 l, compared with 34.1 ± 16.3 l in winter. The highest average yield recorded was for camels at sixth parity, whereas the highest weekly peak was at eighth parity, and highest persistency at fifth parity. Camels that calved during the cold months (November to February) were most productives, with the highest persistency, peak yield, and longest lactation length. Four types of curves were identified corresponding to different parities and milk yield levels. Based on these data, specific models for camels are proposed.

The involvement of plasma leptin in the adaptation of dromedary camels to harsh conditions such as food or water shortages was studied through 2 experiments. In experiment 1, fourteen female camels were either fed at 68% of maintenance energy requirements (MER) during 112 d ( n = 4) or overfed at 134% of MER during the first 56 d and then underfed at 17% of MER the next 56 d (OV-UN, n = 5), or underfed and then overfed for the same durations and energy intake levels (UN-OV, n = 5). Weekly plasma samples showed that leptin, glucose and non-esterified fatty acid (NEFA) concentrations were significantly modulated by energy intake level. NEFA increased sharply but transiently in underfed camels of the UN-OV or OV-UN groups, whereas glucose and leptin concentrations decreased with underfeeding and increased with overfeeding with more significant effects in camels that were previously overfed or underfed, respectively. In experiment 2 twelve female camels were either normally watered ( n = 6) or dehydrated ( n = 6) during 23 d and then rehydrated during 4 d. Dehydration specifically increased blood hematocrit, plasma NEFA and glucose whereas leptin decreased slightly. For both experiments, leptinemia was positively related to hump adipocyte volume. Taken together these results provide new data for a better understanding of lipid and energy metabolism in camels.

Weekly milk samples from ten lactating she camels (Camelus dromedarius) were analyzed regularly for 11 months after parturition. The main values for all samples were 2.54 ± 0.72g/100g fat matter, 3.07 ± 0.30g/100g protein, 4.21 ± 0.37g/100g lactose and 0.76 ± 0.10g/100g ash. Fat content decreased from 3.41% at the first week to 2.29% at 36th week post-partum with rising at the end to 2.95% while protein decreased from 3.44% at week 1 to 2.79% at the end of lactation, and lactose from 4.48% to 3.90%. Ash increased from 0.72% to 0.82% then decreased down to 0.71%. Regarding seasonal variation, maximum level of fat was observed in January (3.46%) and minimum at summer time (2.29% in July). Protein content was maximum in February (3.32%) and minimum in October (2.76%). For lactose, the maximum mean value was 4.38% in February and the minimum in September (3.83%). The ash content was quite variable in January then stable all over the year. All components were highly positively correlated, except between fat and ash content which was not significant. No significant effect of parity, gestation length, calf body weight at birth or adult weight on all milk content. The average total milk production was 1207 L for 11 months range between 875 and 1616 L. The correlation between milk production and milk components are significantly negative.

Trois essais réalisés dans des contextes climatiques et alimentaires différents (Guelmim, Laôyoune, Tadla) et concernant au total 125 dromadaires ont été mis en oeuvre en vue de préciser le statut nutritionnel en cuivre et zinc des camelins au Maroc. Les valeurs moyennes régionales ont varié de 65 à 102 µg/100 ml pour la cuprémie, et de 38 à 59 µg/1où ml pour la zincémie. Exception faite de l'effet de l'âge sur la zincémie, plus élevée chez les jeunes, il n'y a aucune variation significative de la cuprémie et de la zincémie en fonction des facteurs physiologiques (âge, sexe). Les résultats sont discutés en fonction des variations des apports alimentaires dans les différents essais.

International audience; Thirty fattened one humped desert camels were used to examine the effect of season on contractile and metabolic properties of Longissimus thoracis (LT) muscle. Ten camels were slaughtered according to seasons of the year (winter, summer and autumn). Season significantly influenced muscle chemical composition, ultimate pH (pHu) and color. Activities of metabolic enzymes were higher during autumn season compared to summer and winter for phosphofructokinase (+64% compared to both seasons) and for isocitrate dehydrogenase (+35% and +145% in autumn vs. summer and winter, respectively). Quantification of muscle myosin heavy chain isoforms by SDS-PAGE electrophoresis showed only presence of type I and type IIa MyHC in camel muscle and indicated high proportion in winter for type I and in autumn for type IIa with respect to other seasons. Several correlations between different MyHC proportions and enzyme activities were reported. These findings indicated that muscle characteristics in camels are influenced by season.

In order to determine the effect of some factors, as different levels of energy and protein, milking interval, lactation stage, and lactation rank on she-camel performance after weaning of camel-calves, 20 lactating shecamels were divided into four groups, 5 animals each, according to age and weight at last parturition. Groups had randomly allocated to one of four treatments diets. Group A received diet with 13% Crude Protein (CP) and 2.4 MCal Metabolisable Energy (ME). Group B received diet with 13% CP and 3.0 MCal ME. Group C and D received diet with 15% CP and 2.4, 3.0 MCal ME respectively. Diets contain 35/65 (roughage/concentrate, respectively). After 14 days of adaptation period, individual feed offered and orts had been recorded, daily and continued up to entire experimental period of 10 months. Milk yield was recorded two milking time from three consecutive days. The results show that diet (B) gave higher milk yield (MY), Fat Corrected Milk (FCM), Energy Corrected Milk (ECM) and Feed Conversion Ratio (FCR) 8.32, 11.77, 7.47, and 1.38 respectively. Diet (A) has higher fat % content when comparing with the other diets. Treatment did not affect milk composition except on fat and ash percentage. Milk secretion rate for 10 hours milking interval "evening milking" was higher comparing with 14 hours milking interval "morning milking" 397, 353 g/h respectively. Maximum MY, FCM and ECM were at mid lactation. In late lactation MY, FCM, ECM decreased. Higher milk productivity was at 3rd and 6th season of lactation. (Resume d'auteur)

Here, two recent outbreaks of Trypanosoma evansi infection in mainland France and Spain associated with the importation of dromedary camels from the Canary Islands, are reported. The disease is well-known on the Archipelago since 1997 and many efforts have been made towards control and eventual eradication, but some areas still remain affected. Both mainland outbreaks were controlled by means of massive treatments and monthly serological, parasitological and molecular (PCR) evaluations carried out by Valencian Regional Animal Health laboratory and by CIRAD, Montpellier, respectively. Possible causes for the persistence of the parasite in a small area of the Canaries are discussed. T. evansi must be included among the animal health conditions for international trade within the European Union as well as many other countries. Moreover, procedures including diagnosis, curative or preventive treatment and quarantine should be established to insure the status of the animals moving from a country to another.

An abattoir survey on gastrointestinal parasites of the dromedary (Camelus dromedarius) was carried out in March/April 1987 in northern Mali. Parasitological examination of the digestive tract content of 11 dromedaries revealed that Haemonchus longistipes was the predominant parasite with a prevalence as high as 85.7%. The genera Impalaia, Trichostrongylus, Cooperia, and Oesophagostomum were also recovered, but with a lower level of infection and frequency. The larval stage of the canine cestode Echinococcus granulosus was recorded in a single instance.

Hundred and twenty-two camel serum samples (82 from a University farm, 40 from 23 farmers’ stocks) were screened for the serum levels of zinc, copper and iron. Animals were distributed all over the region of the Thar desert of Western Rajasthan (India). The overall mean serum levels in zinc, copper and iron were 85.4 ± 2.5 µg/100 ml (33.3-100.0), 94.3 ± 3.2 µg/100 ml (39.9-160.0) and 107.4 ± 3.0 µg/100 ml (40.0-182.0), respectively. Simultaneously, trace element levels from locally grown common camel feeds (plants and shrubs) consumed by these animals were also analysed. The desert plants concentrations were quite adequate in zinc, iron and manganese, but the value for copper seemed too low. However, if a sufficient quantity of roughage is available the animals can meet requirements. Trace element values from the University farm camels were always higher than those of the farmers’ stocks. The statistical analysis showed significant values in the case of iron, but non-significant ones for zinc and copper. Furthermore, young males showed a slightly lower level in comparison to adults. Generally, the status of zinc, copper and iron in Indian camels were lower than the normal values reported elsewhere. Similarly they were lower in comparison to ruminants (cattle and sheep) from the same region. Some animals showed sub-clinical deficiency levels.

The change in the composition of camel milk in four dromedaries was studied by including the common measured parameters: protein, total fat, lactose, main minerals (calcium, phosphorus, and iron), and vitamin C. The fat matter varied from 4.34% to 7.81% with a slight decrease all along the lactation and a minimal value at the 14th week corresponding to the lactation peak. Those variations were less important for protein content (from 2.58% to 3.64%), but the minimal value was observed at the 14th week also. The lactose varied slightly around its mean of 3.46%. The vitamin C concentration varied from 48 to 256 mg/l with a tendency of increasing all along the lactation. Calcium and phosphorus concentrations were quite parallel and their ratio Ca/P was constant. The minimal values (1.43 g/l for calcium and 1.16 g/l for phosphorus) were observed at the beginning of the lactation. The iron concentrations varied around the mean of 1.73 mg/l.

International audience; The variable domain of heavy-chain camelid antibodies (VHH), exclusively present in the homodimer IgGs (HC IgG), provides valuable ligands for diagnosis, imaging and therapy. These VHHs are efficiently produced from lymphocytes of immunized animals through phage display and recombination biotechnology. For VHH development it is desirable to identify animals with high affinity HC IgG response by monitoring antigen-binding in the course of immunization. The aim of this study was to propose a direct approach on whole plasma samples to distinguish between homodimer IgG and heterotetramer (IgG(1)) responses, and quantify them, using western ligand blotting (WLB). WLB consists here in electrophoretic separation of the target IgG subclasses on the basis of molecular size and binding of (125)I labeled antigen. First, we established the WLB parameters for titration of antigen-binding homodimers in relation to antigen-binding total IgGs in ovalbumin-immunized dromedary plasma samples and demonstrated that the WLB is an alternative to ELISA for IgG subclass titration. As purification of IgG subclasses or availability of IgG subclass-specific antibodies is not necessary, WLB is more direct and practical for screening a large number of samples. Second, WLB was applied to study the pattern of homodimer and heterotetramer responses during the time-course of immunizations against three different types of immunogens. As these patterns can differ between animals and immunogens, the method may be useful for identifying animals displaying the desired antigen-specific homodimer IgG response. Lastly, WLB was also described in its variant form of dot ligand blotting for identifying antigen-binding phages at the final step of a phage display experiment. (C) 2008 Elsevier B.V. All rights reserved.