Camel Milk Samples Research Articles

Rapid detection and spectroscopic feature analysis of mineral content in camel milk using fourier-transform mid-infrared spectroscopy and traditional machine learning algorithms

Camel milk is rich in nutrients and bioactive factors, with mineral content generally higher than that of cow milk, but there is currently no internationally established, rapid, batch-testing method for the mineral content. This study collected samples of camel milk from 113 locations in Xinjiang, China. For the first time internationally, based on the true mineral values determined by ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy) and the extracted mid-infrared spectra data, a quantitative prediction model for 10 key minerals (Ca, Fe, K, Mg, Mn, Na, P, Sr, Zn, and Se) was established using Fourier-Transform Mid-Infrared Spectroscopy (FT-MIRS) and the traditional machine learning algorithm Partial Least Squares Regression. The Rt2 of the test set ranged from 0.61 to 0.91, RMSEt ranged from 2.21ug/kg(Se) to 197.08 mg/kg(K) and the RPDt from 1.59 to 3.28. In addition, the distribution, patterns, and correlations of mineral-related characteristic wavenumbers in camel milk were summarized. This study opens a new avenue for the rapid detection of minerals in camel milk and fills the research gap in in using FT-MIRS to detect mineral content in camel milk.

In vitro assessment of probiotic properties of lactic acid bacteria isolated from camel milk: enhancing sustainable foods

Probiotic properties of isolated lactic acid bacteria (LAB) from sustainable foods including camel milk are the potential research domains. For this purpose, camel milk samples (n = 20), from four different herds of Camelus dromedarius, were processed for the identification of LAB strains based on biochemical profiles followed by amplification and sequence analysis of the 16S rRNA gene. The probiotic characteristics, i.e., acids and bile salts tolerance, antimicrobial susceptibility profiles, hemolytic and antimicrobial activities, auto-aggregation assay, and adhesion to HT-29 epithelial cells were determined. Thirteen out of 20 milk samples were initially found positive for the growth of probiotics or LAB which were further confirmed as Lacticaseibacillus casei (5) and Pediococcus pentosaceus (3). The probiotics/LAB strains showed maximum survival (%) = 92.06 ± 1.82 and 81.35 ± 3.64 against acids and bile salts, respectively. The LAB strains were found sensitive to amoxicillin, ceftazidime, imipenem, linezolid, ofloxacin, tetracycline, tobramycin, and vancomycin. None of the LAB strains showed hemolytic activity. L. casei-04 strain showed a maximum zone of inhibition (15.33 ± 0.58) against multidrug-resistant E. coli AZ1 strain whereas, L. casei-05 showed a maximum zone of inhibition (16.33 ± 1.15) against methicillin-resistant S. aureus Saba-1 strain. L. casei-03 showed maximum percentage auto-aggregation (28.65 ± 1.96) at 4 h while L. casei-01 showed (41.10 ± 3.03) at 24 h of incubation. Maximum adhesion was shown by P. pentosaceus-01 (11.14%) followed by L. casei-02 (9.73%). Altogether, the current findings suggested that camel milk has significant potential of providing probiotics/LAB strains into human food chain and enabling camel milk as potential sustainable food.

Quantification of pesticide residues in milk by HPLC-UV analysis in Gilan province, Iran

ABSTRACT Eighty milk samples, comprising raw cow’s milk, pasteurised milk, ultra-high temperature milk, and camel milk, were collected randomly from supply centres from December 2022 to March 2023 in Gilan province, Iran. Aldrin, diazinon, and dichlorodiphenyltrichloroethane (DDT) were determined using high-performance liquid chromatography. Aldrin and diazinon were observed in all samples. Furthermore, 87.5% of the milk samples were contaminated with DDT. The raw milk sample showed the greatest concentration of aldrin, measuring 9.31 ± 0.80 µg L−1, and there was no significant difference with the camel milk. The samples of camel milk, raw milk, and ultra-high temperature milk demonstrated the greatest levels of DDT, whereas the lowest concentration was detected in pasteurised milk. In all samples, the maximum residue level (MRL) of Codex Alimentarius and the national Iran standard (20 µg L−1 for DDT) was only exceeded by 25.1% of the milk samples.

Camel Milk Resistome in Kuwait: Genotypic and Phenotypic Characterization.

Antimicrobial resistance (AMR) is one of the major global health and economic threats. There is growing concern about the emergence of AMR in food and the possibility of transmission of microorganisms possessing antibiotic resistance genes (ARGs) to the human gut microbiome. Shotgun sequencing and in vitro antimicrobial susceptibility testing were used in this study to provide a detailed characterization of the antibiotic resistance profile of bacteria and their ARGs in dromedary camel milk. Eight pooled camel milk samples, representative of multiple camels distributed in the Kuwait desert, were collected from retail stores and analyzed. The genotypic analysis showed the presence of ARGs that mediate resistance to 18 classes of antibiotics in camel milk, with the highest resistance to fluoroquinolones (12.48%) and disinfecting agents and antiseptics (9%). Furthermore, the results pointed out the possible transmission of the ARGs to other bacteria through mobile genetic elements. The in vitro antimicrobial susceptibility testing indicated that 80% of the isolates were resistant to different classes of antibiotics, with the highest resistance observed against three antibiotic classes: penicillin, tetracyclines, and carbapenems. Multidrug-resistant pathogens including Klebsiella pneumoniae, Escherichia coli, and Enterobacter hormaechei were also revealed. These findings emphasize the human health risks related to the handling and consumption of raw camel milk and highlight the necessity of improving the hygienic practices of farms and retail stores to control the prevalence of ARGs and their transmission.

Sinapic acid attenuates biofilm formation and virulence factor production in methicillin resistant Staphylococcus aureus (MRSA) isolated from raw camel milk: An in vitro and in silico approach

Camel milk is highly nutritious but contamination with biofilm forming methicillin resistant Staphylococcus aureus (MRSA) may pose a serious threat to human health and food safety. Therefore, sinapic acid (SA) was assessed for its in vitro antibiofilm and antivirulence potential against MRSA isolated from raw camel milk samples. SA reduced biofilm formation and production of key virulence functions (exopolysaccharide production, cell surface hydrophobicity and staphyloxanthin production) significantly. Pre-formed biofilms were also reduced by 38–55%. Enhanced reactive oxygen species (ROS) production in MRSA cells treated with SA could plausibly be responsible for cell death and reduced biofilm formation. In silico studies demonstrated that the overall binding energy for SA interaction with AgrA and SarA was −9.882 and −15.076 kcal mol−1, respectively. It is envisaged that SA could be exploited to mitigate biofilm formation in ensuring the safety and quality of food/dairy products and minimizing the risk of MRSA transmission through the food supply chain.

Toxic metal levels in raw camel milk sold in the northern Algerian Sahara

ABSTRACT The consumption of camel milk is gaining popularity in Algeria. This study aimed to determine the concentrations of Lead (Pb), Cadmium (Cd), Nickel (Ni) and Mercury (Hg) in camel milk sold in Southeast Algeria and assess the potential health risks associated with its consumption. 120 samples of camel milk were collected from 10 farms located near the roads in the south of Algeria. Metals were measured using an atomic absorption spectrophotometer with a graphite furnace and Target Hazard Quotients (THQs) were calculated. The mean concentrations were 0.026 ± 0.013 mg/kg, 0.001 ± 0.0002 mg/kg, 0.017 ± 0.002 mg/kg and 0.0005 ± 0.0002 mg/kg for Pb, Cd, Ni and Hg. The THQ was higher for children, suggesting health risks associated with consumption of camel milk for this age group (p < .001). The primary contribution of this study is the establishment of a database on toxic metal levels in camel milk, which can be valuable to manage possible risk associated with metals in milk.

Microbial diversity in camel milk from Xinjiang, China as revealed by metataxonomic analysis.

The quality of raw camel milk is affected by its bacterial composition and diversity. However, few studies have investigated the bacterial composition and diversity of raw camel milk. In this study, we obtained 20 samples of camel milk during spring and summer in Urumqi and Hami, Xinjiang, China. Single-molecule real-time sequencing technology was used to analyze the bacterial community composition. The results revealed that there were significant seasonal differences in the bacterial composition and diversity of camel milk. Overall, Epilithonimonas was the most abundant bacterial genus in our samples. Through the annotated genes inferred by PICRUSt2 were mapped against KEGG database. Non-parametric analysis of the bacterial community prediction function revealed a strong bacterial interdependence with metabolic pathways (81.83%). There were clear regional and seasonal differences in level 3 metabolic pathways such as fat, vitamins, and amino acids in camel milk. In addition, we identified lactic acid bacteria in camel milk with antibacterial and anti-tumor activities. Our findings revealed that camel milk from Xinjiang had serious risk of contamination by psychrophilic and pathogenic bacteria. Our research established a crucial theoretical foundation for ensuring the quality and safety of camel milk, thereby contributing significantly to the robust growth of China's camel milk industry.

Molecular characterization of antimicrobial resistance genes of Staphylococcus aureus isolated from mastitic camel milk in Egypt.

Staphylococcus aureus is one of the most common causes of mastitis worldwide. This study aimed to determine the prevalence and antimicrobial resistance (AMR) patterns of S. aureus in mastitic milk samples collected from camel farms in Matrouh Governorate, Egypt. A total of 200 mastitic camel milk samples were evaluated for S. aureus using both conventional culture-based and molecular-based methods. Antibiotic susceptibility testing of S. aureus isolates was conducted using disc diffusion and agar dilution methods, with antibiotic resistance genes identified through polymerase chain reaction with specific primers. Out of samples tested, 60 (30.00%) were positive for S. aureus. The isolates displayed the highest of resistance against piperacillin-tazobactam (55.00%) followed by trimethoprim- sulfamethoxazole (45.00%) and amoxicillin (40.00%). Half of the isolates were multidrug-resistant (MDR). The AMR genes included methicillin-resistant gene (mecA), β-lactamase gene (blaZ), tetracycline resistance gene (tetK), erythromycin resistance gene (ermB) and vancomycin resistant gene (vanA) were detected in 100%, 100%, 95.00%, 90.00% and 20.00% of the isolates, respectively. In conclusion, the presence of MDRS aureus as a cause of clinical camel mastitis is a significant veterinary and public health concern. These findings highlight the importance of proper antibiotic use in Egyptian camel farms and the need for molecular techniques to fully understand the genetic profile of antimicrobial-resistant S. aureus isolates.

Lipidomic and proteomic profiling identifies the milk fat globule membrane composition of milk from cows and camels

This study was designed to detect lipidomic and proteomic differences in the milk fat globule membrane (MFGM) fractions of cow and camel milk samples. In total, 353 lipid species were detected in these analyses, including 77 PEs, 30 PCs, 28 PIs, 59 SMs, 54 Cers, 13 LPCs, 14 LPEs, 20 PSs, and 4 PGs. These included 54 polar lipid species that differed significantly in abundance between cow and camel milk. Glycerophospholipid metabolism was identified as a core metabolic pathway associated with camel milk composition. Furthermore, 547 proteins exhibiting differential abundance were identified by a label-free proteomics methodology when comparing samples of MFGMfrom camels and cows. Of these proteins, those that differed most in expression between these groups were associated with metabolic pathways, including endoplasmic reticulum activity, endocytosis, and PI3K-Akt signaling. In conclusion, our findings provide a more thorough understanding of the composition of MFGM and its physiological significance, hence offering robust evidence for the potential utilization of camel milk as a nutritional resource in future developments.

Identification of Milk Adulteration in Camel Milk Using FT-Mid-Infrared Spectroscopy and Machine Learning Models.

Camel milk, esteemed for its high nutritional value, has long been a subject of interest. However, the adulteration of camel milk with cow milk poses a significant threat to food quality and safety. Fourier-transform infrared spectroscopy (FT-MIR) has emerged as a rapid method for the detection and quantification of cow milk adulteration. Nevertheless, its effectiveness in conveniently detecting adulteration in camel milk remains to be determined. Camel milk samples were collected from Alxa League, Inner Mongolia, China, and were supplemented with varying concentrations of cow milk samples. Spectra were acquired using the FOSS FT6000 spectrometer, and a diverse set of machine learning models was employed to detect cow milk adulteration in camel milk. Our results demonstrate that the Linear Discriminant Analysis (LDA) model effectively distinguishes pure camel milk from adulterated samples, maintaining a 100% detection rate even at cow milk addition levels of 10 g/100 g. The neural network quantitative model for cow milk adulteration in camel milk exhibited a detection limit of 3.27 g/100 g and a quantification limit of 10.90 g/100 g. The quantitative model demonstrated excellent precision and accuracy within the range of 10-90 g/100 g of adulteration. This study highlights the potential of FT-MIR spectroscopy in conjunction with machine learning techniques for ensuring the authenticity and quality of camel milk, thus addressing concerns related to food integrity and consumer safety.

Determination of aflatoxin M1 (AFM1) in dairy sheep, goats and camel milk in Hail Region, Kingdom of Saudi Arabia and evaluation of different methods reducing its concentrations in milk

ABSTRACT This study aimed to determine aflatoxin M1 (AFM1) in dairy sheep, goats, and camel milk in Hail, Saudi Arabia, and evaluate methods for reducing AFM1. A total of 67 milk samples were collected from Ghazala and Al-Shweimis villages, Hail. AFM1 in milk samples was analyzed using enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC) with fluorescence detection. Results revealed concentration of AFM1 in goat and camel milk samples from Ghazala was higher than that in goat and camel milk samples from Al-Shweimis with a significant difference (p<0.05) using both ELISA and HPLC methods. The mean AFM1 concentration using ELISA for goat milk was (12.96 ± 2.23 ng/l), while the AFM1 concentration for camel milk was (1.54 ± 0.29 ng/l). Microwave heating and boiling are effective methods to reduce the AFM1 in milk. ‏‎‏‎‏The highest AFM1 removal percent was 42.96% by microwave and 12.32 % by boiling milk samples.

Determination of the fatty and amino acid composition of camel milk, milk powder and shubat

Camel milk is considered an essential source of nutrition and an effective remedy with healing properties in treating several diseases. Shubat, a fermented drink made from camel milk, contains easily digestible proteins, determining its nutritional value. Meanwhile, few studies have analysed the fatty and amino acid composition of Bactrian camel milk, milk powder and shubat in Kazakhstan. In this paper, we used the gas chromatography-mass spectrometry method to determine milk the fatty and amino acid composition of Kazakhstan camel milk and camel milk powder and submit samples. As a result, significant differences in the fatty acid and amino acid compositions were observed among samples of raw milk, milk powder and shubat. differences were found in all amino acids. The most representative fatty acids in the three groups were С16:0, С18:0, С18:1n9c, С14:0 FAs. In camel milk samples, among indispensable amino acids, lysine (29.64%) was the highest in concentration, followed by methionine (25.68%). Some polyunsaturated fatty acids (PUFAs) such as С18:3n3c, С20:4n6, С18:3n3c, С20:3n3c 8,11,14 were found only in shubat samples. Furthermore, we revealed a significant decrease in both dispensable (DAA) and indispensable (IDAA) contents in camel milk powder. Meanwhile, an increase in the quantitative content of amino acids has been observed in shubat, especially in threonine (166.86%), aspargine (156.34%), alanine (114.48%), etc. The results provide a theoretical basis for additional studies of camel milk composition of Bactrian camel in Kazakhstan.

Detection of 11 carbamate pesticide residues in raw and pasteurized camel milk samples using liquid chromatography tandem mass spectrometry: Method development, method validation, and health risk assessment

This study aimed to use ultra-high-performance liquid chromatography coupled to a triple-quadrupole mass spectrometer to detect 11 carbamate pesticide residues in raw and pasteurized camel milk samples collected from the United Arab Emirates. A method was developed and validated by evaluating limits of detection, limits of quantitation, linearity, extraction recovery, repeatability, intermediate precision, and matrix effect. Due to the high protein and fat content in camel milk, a sample preparation step was necessary to avoid potential interference during analysis. For this purpose, 5 different liquid-liquid extraction techniques were evaluated to determine their efficiency in extracting carbamate pesticides from camel milk. The established method demonstrated high accuracy and precision. The matrix effect for all carbamate pesticides was observed to fall within the soft range, indicating its negligible effect. Remarkably, detection limits for all carbamates were as low as 0.01 μg/kg. Additionally, the coefficients of determination were >0.998, demonstrating excellent linearity. A total of 17 camel milk samples were analyzed, and only one sample was found to be free from any carbamate residues. The remaining 16 samples contained at least one carbamate residue, yet all detected concentrations were below the recommended maximum residue limits set by Codex Alimentarius and the European Union pesticide databases. Nonetheless, it is worth noting that the detected levels of ethiofencarb in 3 samples were close to the borderline of the maximum residue limit. To assess the health risk for consumers of camel milk, the hazard index values of carbofuran, carbaryl, and propoxur were calculated. The hazard index values for these 3 carbamate pesticides were all below 1, indicating that camel milk consumers are not at risk from these residues.

Prevalence of Camel Mastitis and Its Associated Risk Factors in and around Garowe District, Puntland, Somalia

Mastitis is one of the main issues that cause economic inefficiencies in dairy farms. It has numerous infectious and non-infectious origins and is divided into clinical and subclinical forms. A cross sectional study of camel mastitis was conducted on 88 lactating camels from Garowe District Puntland between May to August 2023 to estimate the prevalence and causes of mastitis, as well the risk factors involved on disease. Prevalence of mastitis was assessed by using California mastitis test (CMT) and bacterial cultured. The overall prevalence of mastitis at animal level was camels examined for mastitis was found a prevalence of 39.7% (35/88) in the current study. The overall quarter level prevalence was 47.7% (168/352). Among these 10(11.4%) and 25(28.4%) were found to be positive with clinical and sub-clinical mastitis respectively, based on clinical examination and mastitis indicator paper (Table 2). Regarding Result analysis showed that there was a statistically significant association (P&lt;0.05) among four the risk factors (tick infected, wound stage of lactation and poor hygienic). Tick infestation and udder lesions were significantly associated with camel mastitis (P &lt; 0.05). Bacteriological examination of CMT along with bacteriological culture methods were used. The study cultured a positive camel milk samples revealed that Staphylococcus spp was the major causative agents for both clinical and sub clinical camel mastitis (45.7%) followed by Streptococcus agalactiae (25.7%), E. coli (14.3%), Klebsiella spp. (8.6%) and Micrococcus (5.7%) respectively. The study demonstrated that camel mastitis is a problem which warrants appropriate control measures in order to improve the health of camels and quality of camel milk production in the study area. The isolation of genera of pathogenic bacteria from the camel milk samples suggests the need for strict hygienic measures during the production and handling of camel milk to reduce public health hazards. Furthermore, public education should be given to improve their awareness about the importance of proper herd health management and hygienic milking practices. In order to minimize the adverse effect of mastitis on the yield, quality of milk and zoonotic impact of the pathogen. The prevalence of camel mastitis in the study area was found to be significantly high. Therefore, implementation of integrated approaches has great importance in the study sites for the prevention and control of mastitis hence minimizing economic loss and prevents significant public health risks.

Does total caloric count of camel milk differ by species, country, season and year of publication: A systematic review, meta‐analysis and meta‐regression

Camel milk is becoming more popular worldwide, and this review aims to estimate the calorie count of camel milk and establish whether calorie value differs in camel milk among different species, countries, seasons and years of publication. The DerSimonian–Laird estimator was utilised to create fix and random‐effects meta‐analysis. This systematic review and meta‐analysis included 7236 camel milk samples, which were extracted from 75 studies. The random effects of camel milk calorie are 61 Kcal/100 mL, and our findings revealed that camel milk calorie values are varied by species, country and season; this variation is mainly related to discrepancies in energy‐containing macronutrients.

Seasonal Variations of Chemical Composition and Microbiological Quality of Camels Milk in Transhumance Nomadic Production System in Shandi Area, Northern Sudan

Transhumance production system is characterized by seasonal movement of the herders to make use of free-range pasture. In this study camel milk samples were collected during different seasons from different she camels’ rearing in transhumance system. The camel milk samples (n= 150) were collected from Western and Eastern Shandi, River Nile State, Sudan. The chemical composition (protein, lactose, total solids and density) and microbiological loads (total bacterial, coliform and yeast and mould) of camel milk were determined. The results showed that overall means for the total solids, protein and lactose content and density of camel milk samples collected from Eastern and Western Shandi during different seasons revealed 12.98±12.84%, 3.58±3.43% and 4.77±4.69% and 1.035±1.030 gm/cm3, respectively. The age and parity number of the she camel revealed highly significant (P&lt;0.01) correlations when compared with total solids, protein, lactose and density. The milk yield was higher in camel reared in Eastern Shandi during winter and Western Shandi during autumn. Also, there were significant (P&lt;0.05) differences in total bacterial, coliform and yeast and mould counts in camel milk collected from Western and Eastern Shandi during the different seasons. However non-significant (P&gt;0.05) differences were found between the two locations in the microbial quality of camel milk. This study concluded that parity number, age of camel, seasons and pasture content are important factors contributing to the variations in camel milk chemical composition. Moreover, the transhumance production system of camel sustains uniform chemical composition of milk, while variations in the microbiological quality are observed.

Effect of microwave heating on physicochemical properties, protein composition and structure, and micromorphology of camel and bovine milk samples

This study aimed to investigate the effect of microwave heating (0, 100, 300, 500, and 700 W; 2 min) on the physicochemical properties, protein composition, and structure and micromorphology of camel and bovine milk samples. Results showed that the physicochemical properties, including pH, protein content, ash content, and soluble solids of both milk samples, decreased after 300 W microwave processing (P < 0.05). The serum albumin and immunoglobulin levels of bovine milk decreased after 300 W processing (P < 0.05), and camel milk whey proteins were more heat resistant than bovine milk proteins. The decreased relative content of κ-casein and the absence of β-lactoglobulin were also found in camel milk during 300 to 700 W processing (P < 0.05). Besides, microwave heating after 300 W induced a conformational transformation and reduced the protein stability of both milk samples. The particle size and scanning electron microscopy images confirmed that the protein structure was changed after 300 W processing. These results indicated that microwave heating at 300 W for 2 min was beneficial to the retention of nutrients (proteins and soluble solids) and the maintenance of protein stability in both milk samples.

Inhibitory activity of Limosilactobacillus reuteri isolated from camel milk against Helicobacter pylori effects in human gastric epithelial cells.

This study aimed to evaluate anti-Helicobacter pylori effects of Limosilactobacillus reuteri 2892 (L. reuteri 2892) isolated from camel milk in GC cell lines (AGS and MKN). From 15 camel milk samples, 132 microbial strains were isolated. Based on microbial and biochemical analysis, 11 potential probiotic candidates were selected. The potential probiotic candidates were assayed for anti-H. pylori activity, and the strain with the highest anti-H. pylori activity was identified genotypically. Based on 16S rDNA sequencing, the selected strain with the best activity against H. pylori (inhibition zone=15.5±0.8) belonged to the Lactobacillus reuteri strain 2892. Cell treatment with H. pylori HC-113 inhibits gene expression of Claudin-4, ZO-1, MUC5AC, and MUC2 in gastric cells, which are attenuated by L. reuteri 2892. The simulative effects of H. pylori HC-113 on the cell migration and invasion of gastric cells were lost when cells were cotreated with L. reuteri 2892. Cell treatment with H. pylori HC-113 promoted cell death, whereas cotreatment with L. reuteri 2892 markedly decreased necrotic and late apoptotic cells. The present study demonstrates that L. reuteri 2892 has potent anti-H. pylori effects and thus can be considered as an alternative protective agent against inflammatory effects of H. pylori in gastric cells.

Bacillus subtilis PM5 from Camel Milk Boosts Chicken Immunity and Abrogates Salmonella entertitidis Infections.

With the practice of a successful livestock industry using antibiotics, which has continued for more than five decades, researchers have long been interested in finding alternatives to antibiotics for poultry production. Probiotics can potentially reduce enteric diseases in livestock and enhance their productivity. The aim of this study was to isolate putative probiotics from camel milk and test them against Salmonella infection as well as host immune development. Thirteen different isolates were obtained from six different camel milk samples from dairy farms in Saudi Arabia. Three of the six isolates (PM1, PM2, PM3, PM4, PM5, and PM6) that showed Gram-positive characters reacted negatively to catalase and hemolytic assays. PM1, PM5, and PM6 showed significant nonpolar surface properties (>51% hydrophobic) and potent antimicrobial activities against avian pathogens, namely S. enterica, S. typhi, S. aureus, and E. coli. PM5 exhibited substantial probiotic traits; therefore, further focus was given to it. PM5 was identified as Bacillus subtilis OQ913924 by the 16S rRNA sequencing method and showed similarity matrix > 99%. An in vivo chicken model was used to access the health benefits of probiotics. After salmonella infection, the mucosal immune response was significantly increased (p < 0.01), and none of the challenge protocols caused mortality or clinical symptoms after infection in intestinal contents. S. enterica organ infiltration in the spleen, thymus, and small intestine was significantly reduced in the B. subtilis PM5-fed chickens. The S. enterica load in chicken feces was reduced from CFU 7.2 to 5.2 in oral-fed B. subtilis PM5-fed chickens. Probiotic-fed chickens showed buffered intestinal content and positively regulated the level of butyric acid (p < 0.05), and intestinal interleukin 1 beta (IL1-β), C-reactive protein (CRP), and interferon gamma (IFN-γ) levels were reduced (p < 0.05). In addition, B. subtilis PM5 showed significant binding to peritoneal macrophages cells and inhibited S. enterica surface adhesion, indicating co-aggregation of B. subtilis PM5 in macrophage cells. It could be concluded that supplementation with probiotics can improve the growth performance of broilers and the quality of broiler chickens against enteric pathogens. The introduction of this probiotic into the commercial poultry feed market in the near future may assist in narrowing the gap that now exists between chicken breeding and consumer demand.

Some Variation Factors of Freezing Point in Camel Milk.

The freezing point degree of milk (FPD) is a classical indicator of cow milk quality. In camel milk, few references are available in the literature regarding the main factors of variation. In the present paper, two methods of FPD determination were used: the Reference method (RM) (using Cryostar) and the Express method (EM), using a milk analyzer (Milkoscan-FT1). The RM was used to determine FPD in 680 bulk raw or pasteurized camel milk samples. Regarding EM, 736 individual milk samples, 1323 bulk samples, 635 samples of pasteurized milk and 812 samples of raw milk used for cheese making were available. The variability of FPD was investigated according to month, lactation stage, milk composition, milk production and microbiological status. Correlations between methods were explored. FPD was highly correlated with most of the milk components and tended to decrease in cases of high contamination by coliforms or high total flora count. However, the weak significant correlations between the two methods indicated the necessity to specifically calibrate an automatic milk analyzer for camel milk.