Heavy Metals Levels in Soil, Water and Feed and Relation to Slaughtered Camels' Tissues (Camelus dromedarius) from Five Districts in Saudi Arabia during Spring.

Soil, water, and forage contaminated with toxic heavy metals such as Pb, Cd, and Co can affect the meat and liver quality of camels raised in this area which affect human health. This study aimed to determine the concentrations of Pb, Cd and Co in soil, water, feed and young camels' carcass tissues (meat, liver, whole blood, rumen fluid and rumen tissue) from five districts in Saudi Arabia during the spring. All samples were wet-digested and analyzed by ICP-OES for heavy metals. In the liver, a significantly higher (p < 0.05) concentration of Pb and Co was observed in camels reared in the central and southern districts, while Cd was found significantly higher in the western and northern districts. The concentration of Pb, Cd and Co in meat of camels in the northern district was significantly higher (p < 0.05), and the meat of camels in the west had a higher (p < 0.05) concentration of Co. In addition, the Cd and Co concentrations in rumen fluid samples from camels in the eastern district were significantly higher than in the central district. A negative correlation between the concentration of Pb and Cd in rumen fluid and rumen tissue was reported. The accumulation of Cd, Pb, and Co in meat and liver was below the recommended maximum limit. Therefore, the harmful risk of human consumption of camel meat and liver is not possible.

Growth Rates, Carcass Traits, Meat Yield, and Fatty Acid Composition in Growing Lambs under Different Feeding Regimes.

A total of 75 male Awassi (mean BW 23.5 ± 2.0 kg; 3 months old) were used in an 84-day trial to investigate the effects of different feeding regimes on productive performance, carcass characteristics, and meat quality, and the fatty acid profile of growing lambs. Animals were randomly allocated into 3 groups of 25 lambs each. The dietary treatments were as follows: (1) whole barley grain (60%) plus alfalfa hay (40%; GB-AH; the basal diet); (2) a concentrate pelleted diet plus alfalfa hay (CP-AH); and (3) a complete pelleted diet (CPD). Feed intake was measured weekly, and all lambs were weighed every two weeks for an evaluation of the productive parameters. Blood samples were collected from all lambs for the measurement of biochemical and enzymatic variables. At the end of the experiment, 13 lambs from each treatment were slaughtered to evaluate the carcass characteristics, meat quality, and fatty acid composition. The final body weight, body weight gain, average daily gain, and feed efficiency of lambs were lowest (p < 0.05) in lambs on the grain and alfalfa diet compared with the other groups. Feeding lambs either the CP-AH or CPD diets resulted (p < 0.05) in increases in slaughter weight, carcass weights (hot and cold), the percentage of liver and shoulder, carcass length, back fat thickness, and the area of longissimus thoracis muscle compared with those lambs on the GB-AF diet. The proportion of saturated fatty acids in meat was greater (p = 0.04) in lambs fed on the GA-AH diet than in those of lambs fed on the pelleted diets. Lambs on the CP-AH diet had (p < 0.05) the highest ratios of PUFA to SFA and omega 6 to omega 3, and the proportion of omega 6. The atherogenic and thrombogenic indexes were lower (p < 0.05) in the CP-AH group compared with the GB-AH group. In conclusion, the results indicate that feeding growing lambs on concentrate pellets instead of whole barley grain improves the growth rate, traits, meat quality, and fatty acid profile, which have important implications for productivity, efficiency, and profitability in the livestock industry.

Regional and Seasonal Variability of Mineral Patterns in Some Organs of Slaughtered One-Humped Camels [Camelus dromedarius] from Saudi Arabia.

Camel products are receiving great interest worldwide because of their high functional properties and nutritive values. Therefore, this study was focused on the variation of copper [Cu], zinc [Zn], manganese [Mn], selenium [Se], iron [Fe], iodine [I], and some heavy metals, cobalt [Co], lead [Pb], and cadmium [Cd], in the blood and tissues of slaughtered camels from five regions in Saudi Arabia [SA] during the summer and winter seasons, because environmental factors vary from region to region. Whole blood, meat, liver, rumen fluid, and rumen tissues were collected from the slaughterhouse in each region during the two seasons. Moreover, samples were prepared and analyzed for trace mineral and heavy metal concentrations using ICP-MS. The data were statistically analyzed as part of a complete randomized design and correlation analysis for season and location using SAS. The findings revealed a pattern in the minerals, with Ca being the only mineral that was unrelated to other minerals in the liver. For lead and cadmium, our mean value in liver [0.40 µg/g] was below the limit of the EU standard for cadmium [0.50 µg/g], while in meat and liver, lead contents [1.62 µg/g and 2.57 µg/g, respectively] were above the limit of the EU standard [0.10 and 0.20 µg/g, respectively]. For meat, the significantly highest positive correlations were observed between P and Mg [R2 = 0.928], Fe and Mn [R2 = 0.860], and Co and Mn [R2 = 0.821]. For rumen tissues, P and Mg were highly correlated [R2 = 0.958] as well as Zn and Mg [R2 = 0.857], Zn and P [R2 = 0.836], and Fe and Ca [R2 = 0.802]. As a result, a region and season reflect variations in mineral concentrations in SA during the summer and winter seasons. Further intensive research is needed to investigate the minerals' biological mechanisms in camels under different environmental conditions.

Blood Trace Element Status in Camels: A Review.

Trace minerals play an important role in animal health and productivity. They are involved also in many physiological activities, and their deficiency causes a variety of pathological problems and metabolic defects, reducing consequently the animal productivity. The demand for animal products in semi-arid areas is rapidly increasing, and the supply is still below the required level, partially due to low animal productivity. Camels (Camelus dromedarius and Camelus bactrianus) are considered one of the main sources of healthy, high-quality meat and milk for human consumption within most of the countries in the semi-arid regions. Despite their efficient adaptation to their environment, camels can suffer from the growth retardation of newborns, low feed efficiency, anemia, poor fertility, poor reproduction and many other metabolic disorders. It is well known that trace mineral deficiencies and trace mineral toxicities can influence camels' production and reproductive efficiency, as well as many aspects of their growth and metabolism. Evaluating the trace minerals status of camels and their variability is an obvious step toward improving camels' productivity and health. Thus, the present article reviews the data regarding the status of trace minerals (copper, zinc, iron, selenium, manganese, cobalt, iodine, fluorine, molybdenum, sulfur, bromide and nickel) in camel blood and their physiological variability, with a focus on their deficiency and toxicity effects.

Effects of the Inclusion of Different Levels of Dietary Sunflower Hulls on the Colostrum Compositions of Ewes.

This study investigated the effects of supplementing different levels of sunflower hulls (SFH) to the complete feed of late-gestation pregnant ewes on the nutritive and fatty acids profile of colostrum at three and 48 h postpartum. In this study, 24 primiparous lactating Naemi ewes were randomly selected at parturition from four dietary groups as follows: (1) C (control), total mixed ration (TMR; 0% SFH), (2) S12, TMR1 with 12% SFH (level 1), (3) S20, TMR2 with 20% SFH (level 2), and (4) S28, TMR3 with 28% SFH (level 3). The body condition scores were estimated 30 days prepartum. Colostrum samples were collected at three and 48 h postpartum to measure the nutritive values and fatty acids profiles. Data were analyzed as a complete randomized design with repeated measures and via Pearson's correlation and regression analyses. The results indicated a numerical correlation (R2 = 0.42; p < 0.09) between the body condition score and both colostrum fat and total solids. SFH increased the colostrum fat % (p < 0.05), especially for S12 and S20, following a cubic trend. Additionally, the colostrum from S12 and S20 ewes had a higher proportion of unsaturated fatty acids (USFAs), omega3 and lower levels of saturated fatty acids (SFAs), other than margaric acid (C17) and stearic acid (C18), SFA/USFA, and omega 6/omega 3. Furthermore, the regression analysis of the fatty acid classes and indices indicated a quadratic relationship between the parameters and SFH levels. The results confirm that the inclusion of SFH at levels greater than 20% may have a negative effect on some fatty acid parameters as a result of the high lignin intake. In conclusion, up to 20% SFH can be used in a complete feed for pregnant ewes without negative effects on the colostrum fat content and fatty acids profiles.

Anti-Coccidial Effect of Rumex Nervosus Leaf Powder on Broiler Chickens Infected with Eimeria Tenella Oocyst.

Coccidiosis a huge economic burden in poultry farms where the pathogen Eimeria harms animal well-being and survival. Besides synthetic anti-coccidial drugs, natural herbs appear to be an alternative way to prevent avian coccidiosis. Rumex nervosus (RN), a phytogenic shrub, has received considerable attention in recent years due to its significant anti-microbial effects; however, limited knowledge exists about its potential anti-coccidial functions. This study was conducted to evaluate the prophylactic and therapeutic activities of RN leaf powder in broilers infected with Eimeria tenella. Infected chickens received a commercial diet containing 1, 3, or 5 g RN powder/kg diet compared to infected broilers that treated with Sacox (PC) or compared to uninfected broilers that received a commercial diet alone (NC). Results showed that RN powder significantly (p < 0.05) reduced the lesion scores and suppressed the output of oocysts per gram (OPG) in chickens' feces. Although RN was unable to minimize the weight gain loss due to emeriosis, RN at level 1 g improved the feed conversion ratio. Therefore, RN powder, at 5 g, possesses moderate anti-coccidial effects and hence could be used to treat avian coccidiosis in field conditions; however, further studies are required to investigate, in vitro or in vivo, the anti-coccidial potential of active ingredients.

Growth Performance, Serum Biochemical Indices, Duodenal Histomorphology, and Cecal Microbiota of Broiler Chickens Fed on Diets Supplemented with Cinnamon Bark Powder at Prestarter and Starter Phases.

Ross 308 broiler chicks (n = 240) aged 1 day were assigned to five groups for eight replicates (six chicks for each) (3♂ and 3♀). Basal dietary groups were supplemented by 2000, 4000, and 6000 mg/kg cinnamon (CN) for 21 days. Basal diet alone was used as a negative control, and basal antibiotic diet (Colimox) was used as a positive control. At 10, 14, and 21 days of age, chicks that received 2000 mg CN and Colimox had a higher body weight, resulting in an increase in body weight gain. CN also resulted in the maximum improvement in the feed conversion ratio and feed efficiency over 1-21 days at the level of 2000 mg/kg. At days 10, the maximum relative breast weight was 2000 mg/kg of CN. Mean serum albumin concentrations, duodenal villus height, and goblet cell density increased (p < 0.05) by 2000 mg/kg of CN, and mean serum globulin and total protein concentrations and crypt depth increased (p < 0.05) by 6000 mg/kg of CN compared with control. Increased cecal Escherichia coli number was CN dose-dependent. In conclusion, dietary inclusion of 2000 mg/kg CN can be applied as an alternative to in-feed antibiotics for broiler starter diet.

Effects of Roughage Quality and Particle Size on Rumen Parameters and Fatty Acid Profiles of Longissimus Dorsi Fat of Lambs Fed Complete Feed.

The fatty acid composition for the longissimus dorsi (LD) fat of carcass sheep is a crucial factor impacting meat quality. We performed a 90-day feeding trial of 25 Naemi lambs to investigate the effects of roughage sources (alfalfa or wheat straw) of two sizes (regular and 1 cm chopped) when fed with pelleted total mixed ration (TMR) on the growth performance, fermentation patterns, and fatty acid (FA) composition of longissimus dorsi (LD) fat. Lambs were randomly assigned to individual pens with five treatment diets, as follows: C, control group with TMR; T1, TMR and regular alfalfa hay; T2, TMR and alfalfa hay chopped to 1 cm; T3, TMR and regular wheat straw; and T4, TMR and wheat straw chopped to 1 cm. Four lambs were randomly selected from each treatment (20 total) and sacrificed. LD fat of the carcass was extracted and analyzed for FA using a gas chromatography-mass spectrometry. Significantly increased feed intake was found in T1 and T2. The FA composition of LD fat in T2 had higher unsaturated fatty acid (UFA), omega-6 (n6), and omega-3 (n3) FA content. Conjugated linoleic acid (CLA) and α-linoleic acid were highest in lambs fed T1 and T2. Feeding different types of roughage, especially alfalfa hay, either regular or chopped, with total pelleted mixed ration is crucial to improving feed intake and body weight gain, as it positively enhances the rumen microbial fermentation process by controlling rumen pH. The FA profiles of meat from lambs fed TMR with regular or 1 cm particle size alfalfa hay (T1 and T2) are recommended for human consumption as a source of healthy FAs.

Influence of sanguinarine-based phytobiotic supplementation on post necrotic enteritis challenge recovery.

In the animal production industry, plant-derived antimicrobial phytobiotics are used as an alternative to antibiotics. Here we investigated the role sanguinarine-based phytobiotic in broiler recovery from Necrotic Enteritis (NE) infection. A total of 100 one-day-old broiler chicks (Ross 308) were randomly allocated to four treatments: negative control CTR (no challenge, no phytobiotic supplementation); positive control NE (NE challenged); phytobiotic SG (sanguinarine phytobiotic, 0.12 g/kg); and SG + NE, (sanguinarine phytobiotic, 0.12 g/kg and NE challenge). Sanguinarine-based phytobiotic supplementation caused significant changes between the groups in performance, livability and histological measurements, however, these changes were not significantly different between SG + NE and NE groups. Significant improvement was detected in NE lesion score of the duodenum and ileum of SG + NE birds compared to NE challenged birds at the end of the production cycle at 40 days old, indicating improved post-NE recovery with the addition of phytobiotic. Sanguinarine-based phytobiotic supplementation in NE challenged birds significantly compensated for a NE associated reduction of Firmicutes and an increase in Bacteroidetes. Functional profile of sanguinarine-based phytobiotic supplemented birds microbiota was distinct from CTR functional profile. NE challenge was associated with a significant increase in cecal propionic acid, while sanguinarine-based phytobiotic supplementation resulted in an increase in cecal acetic acid.

Bacillus subtilis PB6 based probiotic supplementation plays a role in the recovery after the necrotic enteritis challenge.

In poultry production, birds are raised under intensive conditions, which can enable rapid spread of infections, with Clostridium perfringens-caused necrotic enteritis (NE) being one of the most devastating for the industry. The current investigation was conducted to evaluate the effectiveness of Bacillus subtilis PB6 probiotic supplementation on bird's post NE recovery, based on chicken performance, cecal microbiota composition, ileum histomorphometric measurements, and short-chain fatty acid production in the cecum of the birds that were challenged with NE mid-production. Birds were split into four groups, including a negative control, positive control challenged with C. perfringens, group supplemented with B. subtilis probiotic, and NE challenged birds supplemented with B. subtilis probiotic. Following NE challenge birds were allowed to reach the end of production time at 40 days, and samples were collected to estimate if probiotic supplementation resulted in better post-NE recovery. Intestinal lesion score across the duodenum, jejunum, and ileum indicated that at the end of production timeline NE challenged birds supplemented with B. subtilis probiotic had lower intestinal lesion scores compared to NE challenged birds without probiotic supplementation implying improved recovery. Probiotic supplementation improved performance of NE challenged birds only in the post-NE recovery stage. NE challenged birds had a significant increase in cecal propionic acid, which was not observed in NE challenged birds supplemented with B.subtilus. Both B. subtilis supplemented groups (challenged and unchanged) were characterized by a significant rise in cecal acetic and butyric acid. Our results demonstrate that B. subtilis supplementation can assist the birds in dealing with NE outbreak and long term recovery.

Effects of Short-Term Inhibition of Rho Kinase on Dromedary Camel Oocyte In Vitro Maturation.

This is the first report on a biphasic in vitro maturation (IVM) approach with a meiotic inhibitor to improve dromedary camel IVM. Spontaneous meiotic resumption poses a major setback for in vitro matured oocytes. The overall objective of this study was to improve in vitro maturation of dromedary camel oocytes using ROCK inhibitor (Y-27632) in a biphasic IVM to prevent spontaneous meiotic resumption. In the first experiment, we cultured immature cumulus-oocyte complexes (COCs, n = 375) in a prematuration medium supplemented with ROCK inhibitor (RI) for 2 h, 4 h, 6 h, and 24 h before submission to normal in vitro maturation to complete 28 h. The control was cultured for 28 h in the absence of RI. In the first phase of experiment two, we cultured COCs (n = 480) in the presence or absence (control) of RI for 2 h, 4 h, 6 h, and 24 h, and conducted real-time relative quantitative PCR (qPCR) on selected mRNA transcripts. The same was done in the second phase, but qPCR was done after completion of normal IVM. Assessment of nuclear maturation showed that pre-IVM for 4 h yielded an increase in MII oocyte (54.67% vs. 26.6% of control; p < 0.05). As expected, the same group showed the highest degree (2) of cumulus expansion. In experiment 2, qPCR results showed significantly higher expression of ACTB and BCL2 in the RI group treated for 4 h when compared with the other groups. However, their relative quantification after biphasic IVM did not reveal any significant difference, except for the positive response of BCL2 and BAX/BCL2 ratio after 4 and 6 h biphasic IVM. In conclusion, RI prevents premature oocyte maturation and gave a significantly positive outcome during the 4 h treatment. This finding is a paradigm for future investigation on dromedary camel biphasic IVM and for improving the outcome of IVM in this species.

The maternal origin of indigenous domestic chicken from the Middle East, the north and the horn of Africa.

BACKGROUND: Indigenous domestic chicken represents a major source of protein for agricultural communities around the world. In the Middle East and Africa, they are adapted to hot dry and semi-dry areas, in contrast to their wild ancestor, the Red junglefowl, which lives in humid and sub-humid tropical areas. Indigenous populations are declining following increased demand for poultry meat and eggs, favouring the more productive exotic commercial breeds. In this paper, using the D-loop of mitochondrial DNA as a maternally inherited genetic marker, we address the question of the origin and dispersal routes of domestic chicken of the Middle East (Iraq and Saudi Arabia), the northern part of the African continent (Algeria and Libya) and the Horn of Africa (Ethiopia). RESULTS: The analysis of the mtDNA D-loop of 706 chicken samples from Iraq (n = 107), Saudi Arabia (n = 185), Algeria (n = 88), Libya (n = 23), Ethiopia (n = 211) and Pakistan (n = 92) show the presence of five haplogroups (A, B, C, D and E), suggesting more than one maternal origin for the studied populations. Haplogroup E, which occurred in 625 samples, was the most frequent in all countries. This haplogroup most likely originates from the Indian subcontinent and probably migrated following a terrestrial route to these different countries. Haplotypes belonging to haplogroup D were present in all countries except Algeria and Libya, it is likely a legacy of the Indian Ocean maritime trading network. Haplogroup A was present in all countries and may be of commercial origin. Haplogroup B was found only in Ethiopia. Haplogroup C was only detected in the South-Western region of Saudi Arabia and in Ethiopia. CONCLUSION: The results support a major influence of the Indian subcontinent on the maternal diversity of the today's chicken populations examined here. Most of the diversity occurs within rather than between populations. This lack of phylogeographic signal agrees with both ancient and more recent trading networks having shaped the modern-day diversity of indigenous chicken across populations and countries.

Rocking the Boat: The Decisive Roles of Rho Kinases During Oocyte, Blastocyst, and Stem Cell Development.

The rho-associated coiled-coil-containing proteins (ROCKs or rho kinase) are effectors of the small rho-GTPase rhoA, which acts as a signaling molecule to regulate a variety of cellular processes, including cell proliferation, adhesion, polarity, cytokinesis, and survival. Owing to the multifunctionality of these kinases, an increasing number of studies focus on understanding the pleiotropic effects of the ROCK signaling pathway in the coordination and control of growth (proliferation, initiation, and progression), development (morphology and differentiation), and survival in many cell types. There is growing evidence that ROCKs actively phosphorylate several actin-binding proteins and intermediate filament proteins during oocyte cytokinesis, the preimplantation embryos as well as the stem cell development and differentiation. In this review, we focus on the participation of ROCK proteins in oocyte maturation, blastocyst formation, and stem cell development with a special focus on the selective targeting of ROCK isoforms, ROCK1, and ROCK2. The selective switching of cell fate through ROCK inhibition would provide a novel paradigm for in vitro oocyte maturation, experimental embryology, and clinical applications.

Effect of Palm Kernel Meal and Malic Acid on Rumen Characteristics of Growing Naemi Lambs Fed Total Mixed Ration.

This study was conducted to investigate the effect of malic acid and 20% palm kernel meal (PKM) on ruminal characteristics. A total of 32 growing lambs were randomly distributed into control (barley and alfalfa ha), total mixed ration (T1), TMR + 20% PKM (T2), TMR + PKC 20% + 4 mL/day malic acids (T3). Lambs were fed these diets ad libitum for 84 days. The results showed that propionic acid in the rumen fluid increased significantly (p < 0.05) in T1 and T3. Lactic acid concentration of rumen fluid increased significantly (p < 0.05) in T2 while the pH increased significantly. The coloration of rumen and reticulum was improved in T3. In addition, most of the histomorphological features were higher in T3 and T2. We concluded that the addition of malic acid supplementation to lambs fed PKC caused a significant improvement in the rumen pH and decreased lactic acid concentration in growing Naemi lambs.

Microsatellite-Based Genetic Structure and Diversity of Local Arabian Sheep Breeds.

The genetic diversity of the sheep breeds in the Arab countries might be considered to be a mirror of the ecology of the region. In this study, the genetic structure and diversity of sheep breeds from Saudi Arabia (Harri, Najdi, Naemi, Arb, and Rufidi) and Awassi sheep from Jordan as an out-group were investigated using 19 microsatellites. All the breeds had high intra-population genetic diversity expressed as allelic number (7.33) and richness (2.9) and, expected heterozygosity (0.77). Structure analysis revealed three main gene pools underlying the ancestral genetic diversity of the study populations. The first pool had Harri, Najdi, and Rufidi breeds; the second had Naemi and Awassi breeds, and the third had the Arb breed which was significantly differentiated from the other breeds. Factorial correspondence analysis lent further support to the presence of the three gene pools. Although the outgroup Awassi sheep was more clearly differentiated, it still genetically close to Naemi sheep. The differentiation of the Arb breed could have been resulted from geographic and reproductive isolation. On the other hand, the genetic structure of the other two gene pools could be the result of the past and recent gene flow between individuals reared in the region known to be the center for animal husbandry and trading until the current time.

Whole-Genome Resequencing of Red Junglefowl and Indigenous Village Chicken Reveal New Insights on the Genome Dynamics of the Species.

The red junglefowl Gallus gallus is the main progenitor of domestic chicken, the commonest livestock species, outnumbering humans by an approximate ratio of six to one. The genetic control for production traits have been well studied in commercial chicken, but the selection pressures underlying unique adaptation and production to local environments remain largely unknown in indigenous village chicken. Likewise, the genome regions under positive selection in the wild red junglefowl remain untapped. Here, using the pool heterozygosity approach, we analyzed indigenous village chicken populations from Ethiopia, Saudi Arabia, and Sri Lanka, alongside six red junglefowl, for signatures of positive selection across the autosomes. Two red junglefowl candidate selected regions were shared with all domestic chicken populations. Four candidates sweep regions, unique to and shared among all indigenous domestic chicken, were detected. Only one region includes annotated genes (TSHR and GTF2A1). Candidate regions that were unique to each domestic chicken population with functions relating to adaptation to temperature gradient, production, reproduction and immunity were identified. Our results provide new insights on the consequence of the selection pressures that followed domestication on the genome landscape of the domestic village chicken.

Effects of prepartum sustained-release trace elements ruminal bolus on performance, colustrum composition and blood metabolites in Najdi ewes.

The aim of this study was to determine the effect of the supplementation of slow release bolus of selenium (Se), copper (Cu), zinc (Zn), cobalt (Co), phosphorous (P), manganese (Mn), and iodine (I) at late gestation (60 day prepartum) on performance of Najdi ewes and their newborn. Twenty Najdi ewes at late gestation were randomly selected from a herd raised under an intensive system and equally divided into two groups (control and treated). Blood samples were collected from ewes and newborns at parturition. Body weights of newborns were taken at birth, 30 and 60 days. A significant (P < 0.05) increase in Cu and Co in blood of dams treated with boluses with an increase (P < 0.05) in blood P, Zn, Cu, Co, and Se of their newborn lambs were observed. Creatinine and triglyceride were significantly (P < 0.05) low in treated newborn while urea was significantly (P < 0.05) high in the same group. In dams, significantly (P < 0.05) low concentration of triglyceride was observed. Body weight of lambs from treated group at 30 days was significantly (P < 0.05) higher when compared with the control. In conclusion, bolus of trace minerals at late gestation improved some mineral status of ewes and the newborns with higher body weight.

Feasibility of utilising an infrared-thermographic technique for early detection of subclinical mastitis in dairy camels (Camelus dromedarius).

Despite the proven ability of infrared thermography (IRT) technology for early detection of subclinical mastitis in dairy cows/sheep/goats, studies on its diagnostic feasibility in dairy camels are lacking. Sixty-five lactating camels in mid lactation, machine milked twice-daily and managed under intensive conditions were screened to evaluate the feasibility of utilising IRT compared with other routine indicators in detecting subclinical mastitis. Immediately before the morning milking, a portable infrared camera was used to obtain thermograms in duplicate for the front and rear left quarters to determine the udder surface temperature (UST). Thereafter, milk samples from quarters were collected, and processed for California mastitis test (CMT) score and somatic cell count (SCC). In the present study, CMT score was used to define subclinical mastitis and the feasibility of IRT to detect subclinical mastitis was compared with CMT and SCC. According to CMT score, subclinical mastitic udders had an average UST of 1·42 °C greater (P<0·0001) than healthy udders. The relationship between UST and CMT was found to be highly correlated (r=0·77; P<0·001), and UST was linearly increased as the CMT increased [UST (°C)=34·86+0·66×CMT score; R 2=0·65; P<0·001]. Additionally, high correlations were obtained between UST and SCC score (r=0·75; P<0·001) and the relationship between UST and SCC was fitted best to a logarithmic equation [UST, °C=33·39+0·88×Log (SCC, ×103 cells/ml), R 2=0·61, P<0·001]. The cut-off value, sensitivity, specificity and area under the receiver operating characteristics (ROC) curve for UST were 35·15 °C, 0·90, 0·98, and 0·95, respectively, when subclinical mastitis was defined according to CMT score, and were 35·70 °C, 0·89, 0·96 and 0·94, respectively, when categorised according to the obtained SCC threshold (SCC=432 000 cells/ml). In conclusion, IRT, as an indirect non-invasive screening method, was highly feasible for distinguishing subclinical mastitic udders in dairy camels, which is crucial to treat mastitis early and efficiently.

Factors influencing the prevalence of subclinical mastitis in lactating dromedary camels in Riyadh Region, Saudi Arabia.

The purpose of this study was to determine the prevalence of subclinical mastitis in camels in Riyadh, Saudi Arabia and the factors influencing its incidence. A total of 740 quarter milk samples were collected from 47 camel herds belonging to Majahim, Maghatir, Shu'l, and Sufer breeds. California mastitis test (CMT) was used as a screening test for subclinical mastitis. Samples giving negative or trace CMT scores (0) were assigned to healthy quarters, while those giving positive scores of 1+ to 3+ were assigned to subclinically affected quarters. Logistic regression was used to assess the association of breed, parity, and stage of lactation with the prevalence of subclinical mastitis. Milk fat, protein, lactose, solid nonfat percentages and Na, Ca, and K concentrations were compared in CMT-positive versus healthy quarters. One third (33%) of tested quarters had subclinical mastitis based on CMT. The estimated probability of subclinical mastitis with the combined effects of breed, parity, and stage of lactation ranged from 15.8% to 54.6%. The risk of subclinical mastitis increased significantly with parity and with the early stage of lactation. The Shu'l breed had significantly higher prevalence of subclinical mastitis than other breeds. Significant decreases in protein, lactose, and solid nonfat, Ca and K concentrations and increase in Na concentrations were associated with subclinical mastitis. In conclusion, subclinical mastitis is prevalent in Saudi camels, and its incidence is influenced by breed, parity, and stage of lactation.