Ruminant Milk Research Articles

Modification of the existing maximum residue levels for triclopyr in animal commodities.

In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant Corteva Agriscience International Sàrl submitted a request to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for the active substance triclopyr in animal commodities. The data submitted in support the request were found to be sufficient to derive MRL proposals for swine and ruminant edible commodities and for ruminant milks considering residue levels expected for the intended uses on grassland. Adequate analytical methods for enforcement are available to control the residues of triclopyr on the commodities under consideration at the validated limit of analytical quantification (LOQ) of 0.01 mg/kg. Based on the risk assessment results, EFSA concluded that the short-term and long-term intake of residues resulting from the uses of triclopyr according to the reported agricultural practices and the derived MRLs in products of animal origin is unlikely to present a risk to consumer health. The consumer risk assessment is indicative pending the submission of the confirmatory data requested under the MRL review.

Prospective nutritional, therapeutic, and dietary benefits of camel milk making it a viable option for human consumption: Current state of scientific knowledge

For over five thousand years, people in Asia and Africa have known about the health benefits of camel milk. Thus, it is used not only as a food source but also as a medicine. The similarities between camel milk and human milk have been scientifically proven. Camel milk is unique among ruminant milk because it is high in vitamins C and E and low in sugar and cholesterol. Still, it contains a wide variety of beneficial minerals (including sodium, potassium, iron, copper, zinc, and magnesium), besides being rich in several nutrients, including monounsaturated and polyunsaturated fatty acids, serum albumin, lactoferrin, immunoglobulins, lysozyme and the hormone insulin. Because of these components, many medical professionals now recommend camel milk as a treatment for various human ailments. It has been demonstrated to be effective in treating gastrointestinal issues, Type 1 diabetes, and food allergies. As a bonus, camel milk has been utilized to cure autism, lower cholesterol, prevent psoriasis, heal inflammation, aid tuberculosis patients, boost the body's natural defences, and impede the spread of cancer cells. Those who have problems digesting lactose may still be able to tolerate it. Conversely, camel milk can also help reduce an excessively high bilirubin, globulin, and granulocyte count. Drinking camel milk does not affect the erythrocyte sedimentation rate, hemoglobin concentration, and leukocyte count. The proteins in camel milk have an adequate ratio of critical amino acids. Immunoglobulins, which fight disease, are contained inside, and their small size allows antigens to penetrate and boosts the immune system's efficacy. This article highlights the health benefits and medicinal uses of camel milk.

Effects of raw and fermented rapeseed cake on ruminal fermentation, methane emission, and milk production in lactating dairy cows

The objective of this study was to evaluate the effects of replacing raw rapeseed cake (RC) with fermented rapeseed cake (FRC) in the diet of dairy cows on methane (CH4) production, ruminal fermentation, and milk production, composition, and fatty acid composition. The Hohenheim gas test (exp. 1) was initially used to evaluate RC and FRC as substrates. Following batch fermentation, an in vitro study (exp. 2) was performed to assess the effects of replacing RC with FRC at 28.75, 57.5, 86.25, and 115 g/kg (FRC25, FRC50, FRC75, and FRC100) in the total mixed rations (TMR). Based on the in vitro results, the control TMR (115 g/kg dry matter (DM) of RC; CONRC) and experimental TMR (115 g/kg DM of FRC; FRC100) were chosen for an in vivo assessment. In exp. 3, four ruminally cannulated cows were used in a replicated 2 (group) × 2 (period) crossover design and fed the TMR ad libitum. In exp. 4, twenty multiparous Polish Holstein-Friesian cows in their mid-lactation (148 ± 26 d in milk) were used in a completely randomized design. The cows were fed a partial mixed ration without the RC and FRC, and the RC and FRC were supplied in a concentrate feeder at 2.65 kg/d/cow. The FRC100 markedly decreased CH4 production by 12% and archaeal population without adversely affecting nutrient digestibility. The molar proportion of propionate was increased, and the molar proportion of acetate and butyrate and acetate to propionate ratio were decreased by FRC100. No significant effects on milk production or composition, except an increase in milk urea concentration, were observed in cows fed FRC100. Milk C18:2 cis-9, trans-11 concentration was greater, and n-6 to n-3 fatty acid ratio was lower for FRC100 than CONRC. In-situ ruminal degradation of RC and FRC were explored using in-sacco techniques (exp. 5). The potential degradation and effective degradability of the DM, organic matter, and crude protein were significantly higher for FRC than RC. These results suggested that FRC could mitigate enteric CH4 production by decreasing archaeal abundances without adversely affecting milk production and ruminal fermentation in lactating cows.

Effect of low dietary concentrations of Acacia mearnsii tannin extract on chewing, ruminal fermentation, digestibility, nitrogen partition, and performance of dairy cows

The supplementation of dairy cows with tannins can reduce the ruminal degradation of dietary protein and urine N excretion, but high concentration in the diet can impair ruminal function, diet digestibility, feed intake, and milk yield. This study evaluated the effect of low concentrations (0, 0.14, 0.29, or 0.43% of diet in DM basis) of a tannin extract from the bark of Acacia mearnsii (TA) on milking performance, dry matter intake (DMI), digestibility, chewing behavior, ruminal fermentation, and N partition of dairy cows. Twenty Holstein cows (34.7 ± 4.8 kg/d, 590 ± 89 kg, and 78 ± 33 d in lactation) were individually fed a sequence of 4 treatments in 5, 4 × 4 Latin squares (with 21-d treatment periods, each with a 14-d adaptation period). The TA replaced citrus pulp in the total mixed ration and other feed ingredients were kept constant. Diets had 17.1% crude protein, mostly from soybean meal and alfalfa haylage. The TA had no detected effect on DMI (22.1 kg/d), milk yield (33.5 kg/d), and milk components. The proportions in milk fat of mixed origin fatty acids (16C and 17C) and the daily secretion of unsaturated fatty acids were linearly reduced and the proportion of de novo fatty acids was increased by TA. Cows fed TA had linear increase in the molar proportion of butyrate and linear reduction in propionate in ruminal fluid, whereas acetate did not differ. There was a tendency for the ratio of acetate to propionate to be linearly increased by TA. Cows fed TA had a linear reduction in the relative ruminal microbial yield, estimated by the concentrations of allantoin and creatinine in urine and body weight. The total-tract apparent digestibility of neutral detergent fiber, starch, and crude protein also did not differ. The TA induced a linear increase in meal size and duration of the first daily meal and reduced meal frequency. Rumination behavior did not differ with treatment. Cows fed 0.43% TA selected against feed particles >19 mm in the morning. There were tendencies for linear decreases in milk urea N (16.1-17.3 mg/dL), urine N (153-168 g/d and 25.5-28.7% of N intake), and plasma urea N at 6, 18, and 21 h postmorning feeding, and plasma urea N 12 h postfeeding was reduced by TA. The proportion of N intake in milk (27.1%) and feces (21.4%) did not differ with treatment. Reductions in urine N excretion and milk and plasma urea N suggest that TA reduced ruminal AA deamination, whereas lactation performance did not differ. Overall, TA up to 0.43% of DM did not affect DMI and lactation performance, while there was a tendency to reduce urine N excretion.

Characteristics of Red Deer (Cervus elaphus) Milk: Lactational Changes in Composition and Processing Impacts on Structural and Gelation Properties.

In an increasingly diversified global market, milk of minor dairy species has gained interest as a novel and premium source of nutrition. Relative to the major dairy species, much is lacking in our understanding of red deer (Cervus elaphus) milk. In this study, we characterized the compositions (macronutrients, minerals, fatty acids, and proteins) of red deer milk and their variations throughout lactation. We also investigated the structures, physical properties, and gelation (acid- and rennet-induced) properties of deer milk and how they are impacted by typical processing treatments (e.g., homogenization and pasteurization). We identified unique features in the composition of deer milk, including being richer in protein, fat, calcium, zinc, iodine, branched-chain fatty acids, and α-linolenic acid than other ruminant milks. Different deer milk components displayed diverse variation patterns over the lactation cycle, many of which were different from those demonstrated in other ruminant species. Other physicochemical features of deer milk were identified, such as its markedly larger fat globules. Processing treatments were demonstrated to alter the structural and gelation properties of deer milk. Most of the gelation properties of deer milk resembled that of bovine milk more than ovine and caprine milks. This study furthers our understanding of red deer milk and will aid in its processing and applications in novel products.

Permafrost preservation reveals proteomic evidence for yak milk consumption in the 13th century

Domesticated yaks endure as iconic symbols of high-altitude frozen landscapes, where herding communities depend on their high-fat milk, transport, dung, and natural fibers. While there is established proteomic evidence for ancient consumption of ruminant and horse milk in the mountains and steppes of northern Eurasia, yak dairy products have yet to be detected. Yak domestication and the species’ dispersal from Tibet into the mountainous zones to the north are also poorly resolved due to a paucity of zooarchaeological data. To examine the potential of paleoproteomics to shed light on domesticated yak in Mongolia, we analyzed human dental calculus from Mongol era elite individuals recovered from permafrost burials in Khovsgol province, where people continue to herd yak to this day. We report the first evidence for yak dairy consumption, linked to local resource control. In addition, we confirm a large diversity of recovered whey, curd, tissue, and blood proteins, likely reflecting the excellent preservation conditions found at permafrost sites.

Global contributions of milk to nutrient supplies and greenhouse gas emissions

Globally, ruminant production systems used to synthesize meat and milk differ tremendously in terms of their efficiency, productivity, and environmental impacts. Regardless of this variability, milk has been repeatedly identified as an essential source of nutrients for humans. The objective of this work was to characterize global contributions of fluid milk to human food and nutrient supplies, greenhouse gas emissions, and water withdrawal. Data were leveraged from the United Nations Food and Agriculture Organization to estimate global supplies of agricultural products. Trade of agricultural products and waste of those products, along with use of human food for livestock feed were accounted for before estimating human nutrient supplies. The contributions of milk to human-edible nutrient supplies were then enumerated in terms of their proportion of total nutrients supplied by the agricultural system and in terms of the human population's requirement for that nutrient. We identified that fluid milk provides over 10% of consumable supplies of vitamin B12, vitamin A, riboflavin, and calcium available for humans globally. In terms of human nutrient requirements, milk provides sufficient vitamin B12 to meet the needs of over 60% of the global population, riboflavin to satisfy 50% of the population, and calcium and phosphorus for over 35% of the population. Compared with other foods, milk ranked among the highest in terms of nutrient-to-calorie ratio for numerous amino acids, phosphorus, calcium, and riboflavin. Conditional dependencies were identified between greenhouse gas emissions and ruminant milk and meat, but not between water withdrawal and milk production. When evaluating the trade-offs in nutrient use versus nutrient provision for producing milk or producing all ruminant products, the production of ruminants worldwide was associated with both net increases and net decreases of several key nutrients. Continued work focusing on strategies to reduce the environmental impact of milk production will improve the utility of milk for feeding the growing global population.

Effect of incremental amounts of Asparagopsis taxiformis on ruminal fermentation and methane production in continuous culture with orchardgrass herbage

Enteric methane (CH4) emissions from ruminants are a significant contributor to total greenhouse gas emissions from the livestock sector. Previous research has demonstrated that the red seaweed Asparagopsis taxiformis strongly inhibits ruminal methanogenesis, but its effects on CH4 production, nutrient digestibility, and ruminal fermentation when added to a cool-season herbage diet have not been assessed. A 4-unit, single-flow continuous culture fermentor system fed orchardgrass (Dactylis glomerata L.) herbage was used to assess the effects of incremental addition of dietary A. taxiformis (0, 5, 10, or 15 g/kg DM) on nutrient digestibility, volatile fatty acid (VFA) concentration, pH, CH4 production, and N metabolism. Treatments were randomly assigned to fermentors in a randomized block design with 7 d of treatment adaptation and 3 d of sample collection. Fermentors were fed a total of 76 g of DM per day, split equally into 4 feedings (07:30, 10:30, 14:00, and 19:00 h). In the last 3 d of each experimental period, daily samples of total effluent were taken for analyses of ammonia N and VFA. One liter of effluent was collected daily (3 L total) for a composite sample that was blended and lyophilized for analysis of DM, ash, neutral and acid detergent fiber, crude protein, and total purines. Headspace CH4 concentration in each fermentor was measured every 15 min (192 readings/d) using a Fourier transform infrared gas analyzer, and pH was recorded every 2 min. Data were analyzed using the GLM procedure of SAS with orthogonal polynomial contrasts. Methane production in fermentors receiving all 3 levels of A. taxiformis was reduced by 99.9% within the first 24 h of each experimental period and remained predominantly below the limit of detection for the remaining 9 d. Apparent digestibility of neutral and acid detergent fiber, as well as apparent and true DM digestibilities, linearly decreased with A. taxiformis inclusion. Total VFA concentration decreased quadratically, and molar proportion of acetate decreased in a cubic manner. Overall, A. taxiformis acutely inhibited CH4 production in continuous cultures fed orchardgrass herbage, but also negatively affected fiber digestibility and total VFA concentration, especially at higher feeding rates. In vitro results indicated that A. taxiformis could be effective in reducing enteric CH4 production in grazing ruminants, but in vivo research is needed to determine how A. taxiformis may impact ruminal fermentation and milk production or average daily gain in grazing systems.

The effects of fermented cassava pulp with yeast waste and different roughage-to-concentrate ratios on ruminal fermentation, nutrient digestibility, and milk production in lactating cows

The study's goal was to evaluate the impact of concentrate diets containing fermented cassava pulp with yeast waste (CSYW) with various roughage to concentrate ratios (R:C) on ruminal fermentation, nutritional digestibility, milk production, and milk composition in lactating cows. Four mid-lactation Thai crossbred dairy cows were randomly assigned a 2 × 2 factorial arrangement in a 4 × 4 Latin square design, weighing 440 ± 60.0 kg (75% Holstein Friesian and 25% Thai native breed), and having 90 days-in-milk (DIM). The different dietary treatments consisted of the following: factor A: soybean meal (SBM) and replacing SBM with CSYW at 100% dry matter (DM) in the concentrate diet, whereas factor B consisted of varying the R:C ratio from 60:40 to 50:50. An interaction effect between protein source and R:C ratio on intake was not observed (P > 0.05). The CSYW-diet did not affect the intake of concentrate and rice straw. However, when the R:C ratio was changed to 50:50, there was a significant increase in the apparent digestibility of neutral detergent fiber and acid detergent fiber (P < 0.05). There was no evidence of an interaction effect between CSYW and the R:C ratio on the parameters of the rumen, the microorganisms in the rumen, or blood urea-nitrogen. The concentration of ammonia-nitrogen in the rumen, however, significantly increased (P < 0.05) when animals were given a concentrated diet containing CSYW. Total VFA, C2:C3 ratios, acetic acid (C2), propionic acid (C3), butyric acid (C4), and methane levels were unaffected by the replacement of SBM with CSYW in concentrate diets or the R:C ratio given to lactating cows (P > 0.05). There was no evidence of an interaction between CSYW and the R:C ratio across any and all milk-related parameters (P > 0.05). The R:C ratio had no effect on milk production or composition (P > 0.05). With the exception of milk protein (P < 0.05), milk yield and milk composition were not affected by replacing SBM with CSYW in concentrate diets (P > 0.05). The concentration of protein in milk produced by animals fed a CSYW-diet increased from 3.05 to 3.25%. On the basis of this research, it is recommended that CSYW be used as a protein source in a concentrate diet in place of SBM with a R:C ratio of 60:40 or 50:50.

Characterization of Cow, Goat, and Water Buffalo Milk Fat Globule Lipids by High-Performance Thin Layer Chromatography

Ruminant milk is an essential part of the human diet and is widely accepted as a major nutrient source in developing countries. However, the polar and neutral lipid content variation in milk fat globules (MFG)among cow, goat, and water buffalo is poorly understood. This study used high-performance thin layer chromatography to identify and quantify five major polar (PL) and three neutral lipids (NL) from the MFG of cow, goat, and water buffalo. Optimal separation was achieved for PLs using chloroform: methanol: water (65:25:4), and hexane: diethyl ether: acetic acid (70:30:1) for NLs. The lower detectable (0.12 to 1.53 μg/mL) and quantification (0.12 to 1.53 μg/mL) limits indicated the high sensitivity of the method. Quantification at 540 nm showed the highest abundance of phosphatidylethanolamine and triglycerides. Fat globules were further characterized for size and microstructural properties, which revealed smaller globules in goats (0.99 ± 0.04 μm) than cows (1.85 ± 0.03 μm) and water buffaloes (2.91 ± 0.08 μm), indicating a negative correlation with PL but a positive correlation with NL. The variation in lipid quantity among different animal species suggests more research to support their selection as a suitable source for developing functional food to impact human health positively.

PreCowKetosis: A Shiny web application for predicting the risk of ketosis in dairy cows using prenatal indicators

Ketosis is considered to be the most important metabolic disease affecting dairy herds, surpassing ruminal acidosis and milk fever. On dairy farms, assessment and monitoring of ketosis risk are necessary for the health management of dairy cows. Changes in the content of hematological and serum biochemical parameters are commonly used to monitor ketosis in dairy cows. However, the collection and detection of these indicators are complex and may lead to stress reactions in cows. This study attempted to predict the risk of ketosis in dairy cows using machine learning models based on noninvasive prenatal indicators of parity, body condition score, dystocia score, daily rumination time, daily activity, and season of calving. Results showed the extreme gradient boosting (XGBoost) model had the highest prediction ability and the most accuracy, compared to random forest (RF), support vector machine (SVM), artificial neural network (ANN), and K-nearest neighbor (KNN). In the XGBoost model, daily rumination time (60.15%) and daily activity (16.73%) were identified with the highest percentage contribution to the model, followed by parity (10.41%), body condition score (6.42%), season of calving (4.23%), and dystocia score (2.06%). The probability of ketosis increased with decreasing daily rumination time and daily activity. Moreover, parity 3+ and summer may also increase the probability of ketosis. Finally, an open Shiny web application for predicting the risk of ketosis in dairy cows based on the XGBoost model was developed (https://2xzl2o-neaop.shinyapps.io/PreCowKetosis/). The application PreCowKetosis can provide decision support for researchers and farmers to prevent ketosis in dairy cows.

Polyunsaturated fatty acids and rumen undegradable protein alter ruminal fermentation and milk fatty acid profiles in dairy cows

ABSTRACT The present study evaluated the effects of incorporating polyunsaturated fatty acid (PUFA)- and rumen undegradable protein (RUP)-enriched feeds on ruminal fermentation, methane production, milk yield and milk FA profiles in dairy cows. Experiment 1 was carried out on 12 multiparous HF dairy cows in mid-lactation (106 ± 18.6 days in milk, 13.1 ± 1.67 kg/d of milk). Environmental conditions throughout the experiment were 34.5 ± 1.9 8°C, 58.0 ± 2.65% relative humidity and 85.7 ± 2.71 temperature–humidity index. Cows (n = 6/group) were randomly allocated to a control diet (Ctrl) consisting of corn silage and concentrate (F:C 60:40) containing 27.2% RUP in the crude protein (CP) or a treatment diet (Trt) consisting of 58.3% corn silage, 29.6% concentrate, 3.24% roasted soybean meal, 5.82% corn dried distiller grains with solubles and 3% added oil, which contained linseed, sunflower and tuna crude oil (1:1:1, wt/wt). The Trt diet contained 35.0% RUP in the CP. Experiment 2 was conducted in vitro using ruminal fluid collected from three Holstein Friesian dairy cows. The experimental design and diets were the same as in Exp. 1. Dry matter intake (DMI) tended to be lower (P = 0.06) in the Trt group. No difference in milk yield was detected, but the lower (P < 0.01) milk fat was measured in the Trt group (2.82% vs. 3.81%). Feed efficiency (milk/DMI) tended to be greater (P = 0.06) in the Trt cows (1.08 vs. 0.88). Lower 18:0 (5.73% vs. 8.29%), but greater concentrations of c9,t11 CLA (1.88% vs. 0.34%), c9,c12 18:2 (1.55% and 0.69%) 18:3n-3 (0.30% vs. 0.12%) and 22:6n-3 (0.17% vs. 0%) were detected in milk fat of cows fed Trt (P < 0.01). Atherogenicity and thrombogenic indices were lower (P < 0.01) with Trt. Concentrations of ruminal total volatile fatty acids and methane, which was assessed by production of volatile fatty acids, were 10.2% and 11.7% lower P < 0.01) in the Trt group. In conclusion, incorporating PUFA- and RUP-high feeds in lactating cow diets in the tropics causes a reduction in concentrations of ruminal VFA, methane production and milk fat while improving aspects of milk quality without affecting milk production.

RAPID METHOD FOR SIMULTANEOUS DETERMINATION OF CIS-9, TRANS-11 AND TRANS-10, CIS-12 CONJUGATED LINOLEIC ACID ISOMERS IN MILK BY GC-FID

Ruminant milk is the lead source of conjugated linoleic acid (CLA) in the human diet, with cis-9, trans-11 CLA being the major among all. Small amounts of trans-10, cis-12 CLA are also found in synthetic supplements. Since both isomers are biologically active with potential health benefits, there is great interest in quantifying them for quality control routines. An alternative method for the analysis of the aforementioned CLAs by fast gas chromatography (GC) is discussed in the present study. The fatty acid methyl ester mixture obtained by alkaline catalysis was injected into a GC equipped with a flame ionization detector (FID) and fitted with an ionic liquid SLB-IL111 chromatographic column (15 m × 0.10 mm × 0.08 µm). Separation was achieved in less than 5 min using a 168 °C isotherm run. Both CLA isomers were quantified by using of single point standard addition statistical approach. Results were contested to those obtained using the recommended 100 m long CP-Sil88 capillary column and none evidence of significant differences was found within 95% confidence interval. Therefore, the proposed method could be valuable to focused regulatory routines of large numbers of samples with greater analytical frequency.

Survival of lactic acid bacteria when using the developed yogurt from the milk of small cattle under in-vitro conditions

Functional nutrition is the use in everyday life of products of natural or artificial origin, which have a regulatory effect on the physiological functions, biochemical reactions of a person through the normalization of his microecological status. Cow remains a common raw material for yoghurts. In this article, the milk of small ruminants is considered as a raw material. The functionality of yogurt, shelf life, survival of bacteria in in vitro conditions are being studied. The purpose of the article is to identify the number of live microorganisms in terms of storage from - days, and in vitro conditions. Therefore, we chose the second method in order to study the viability of probiotics in the developed yogurts from sheep and goat milk, by modeling the gastrointestinal tract in vitro in comparison with the information available in the scientific literature. The studies were carried out in two stages: the stage of activation and preparation of strains, the second stage of modeling the gastrointestinal tract and checking at each stage of digestion. In this study, there were 8 samples, all samples showed a constant number of viable cells during 14 days of storage, even at 21 days there were viable bacteria. The number of viable cells was maintained at 107 and 106 CFU/mL until the 21st day of storage at 4 °C. The difference between BB counts may be related to its sensitivity to oxygen. Based on the experimental data obtained, it can be concluded that the samples showed a good initial concentration of probiotics - above 1010 CFU/g, after activation, as well as after simulating passage through the gastrointestinal tract with an average decrease of 106 and 107 CFU/g, which proves the therapeutic ability yoghurts from sheep's milk obtained according to the claimed method.

Genetic diversity of Brucella melitensis isolates from sheep and goat milk in Iran.

The genetic diversity of Brucella strains has not been fully understood. To investigate this, the genetic characteristics of 64 isolates of Brucella melitensis from sheep and goats' milk were studied using random fragment length polymorphism (RFLP) and multiple locus variable-number tandem repeat analysis (MLVA-16) methods developed in Orsay, France (MLVA-16Orsay). The RFLP analysis revealed that all 64 isolates were of biovar one. The MLVA-typing showed that one sample was simultaneously infected with two strains of B. melitensis and the genotype of 65 isolate was analyzed. Four genotypes (47, 42, 43, and 63) were identified using MLVA-8 (panel 1), whereas six genotypes (138, 125, 116, 108, and two unknown genotypes) were identified using MLVA11 (panels 1 and 2A). From the review of MLVA-16 (panels 1, 2A, and 2B), panel 2B showed a very high discriminatory power. Two loci of Bruc04 and Bruc30 from this panel had diversity index values higher than 0.71 and the average diversity index was 0.619. So MLVA-16Orsay 34 showed the genotype indicating a low genetic homogeneity among the isolates. The findings of MLVA genotyping of the isolates suggest that strains of B. melitensis isolated from the milk of small ruminants in Iran are most closely related to the isolates from neighboring countries of the Eastern Mediterranean group. To the best of our knowledge, this is the first study to indicate the potential use of MLVA genotyping for simultaneous detection of specimen contamination using two different B. melitensis biovars.

Effect of vegetable coagulant and lamb rennet on physicochemical composition, fatty acid profile and lipid quality indices of a traditional fresh cheese (Jben)

Jben is a popular traditional cheese in Algeria and North Africa, usually made from raw ruminant's milk, especially cow. Artisanal production methods are still used in many regions, especially during the abundant milk production season. This study aimed to evaluate and compare the effect of various coagulants (of animal and plant origin) on physicochemical parameters, fatty acids (FAs) profile and lipid quality indices in the traditional fresh cheese "Jben". These parameters were analyzed in Jben samples made with vegetable rennet (CVR) from Cynara cardunculus, which were compared with Jben cheeses made using lamb rennet (CLR). The physicochemical characterization showed that pH, titratable acidity, dry matter, fat, and protein contents were 6.19, 92.5 °D, 43.7 g/100 g, 23.4 g/100 g and 15.2 g/100 g cheese, respectively for CVR; and 5.21, 80.3 °D, 50.1 g/100 g, 20.6 g/100 g and 13.8 g/100 g cheese, respectively for CLR. The FAs composition was determined using gas chromatography-mass spectrometry (GC-MS) method. For CLR, FAs comprised 0.09–28.8% saturated fatty acids (SFAs), 0.85–27.68% monounsaturated fatty acids (MUFAs), and 3.22% of polyunsaturated fatty acids (PUFAs); whereas FAs of CVR included 0.22–27.81% SFAs, 1.10–28.16% MUFAs, and 3.07% PUFAs. The predominant FAs identified in all cheeses were C16:0, C18:0 and C18:1(9), with 28.80%, 13.37%, and 27.68% of total FAs, respectively for CLR, and 27.81%, 13.07%, and 28.16%, respectively for CVR. The lowest level of SFAs was observed in CVR, which had the most beneficial health indices with atherogenicity index (2.19), thrombogenicity index (2.91), desirable fatty acid ratio (49.40%) and high hypocholesterolemic/hypercholesterolemic fatty acid ratio (0.72).

Comparison of Milk Odd- and Branched-Chain Fatty Acids among Human, Dairy Species and Artificial Substitutes.

The aim of the study was to compare odd and branched-chain fatty acids (OBCFA) of milk from sheep, goat, cow, buffalo, donkey, human, and formula milk. Ruminant, monogastric, and human milks have different concentrations of these fatty acids (FA). To highlight the differences on OBCFA, a total of 282 individual milk samples were analyzed by gas chromatography. The OBCFA were found higher in ruminant than non-ruminant milks (p &lt; 0.05). Among ruminants, sheep milk had the highest OBCFA (4.5 g/100 g of total FAME), whereases the lowest values were found in formula milk (0.18 g/100 g of total FAME). Regarding individual linear odd-chain FA (linear-OCFA), C11:0 was found higher in donkey milk than others, while sheep and buffalo milks had the greatest concentration of C15:0. Among BCFA, the iso-BCFA were higher than anteiso-BCFA in all considered milks. The isoC17:0 showed the highest concentration in all milks except for donkey and buffalo, which showed higher concentration of isoC16:0 than others. In conclusion, ruminant milks are different in terms of these FA compared to human milk and its substitutes. However, the greatest differences were found with formula milk, suggesting that this product needs the implementation of these FA to be more similar to human milk composition.

Elucidating genes and gene networks linked to individual susceptibility to milk fat depression in dairy goats.

Dietary supplementation with marine lipids modulates ruminant milk composition toward a healthier fatty acid profile for consumers, but it also causes milk fat depression (MFD). Because the dairy goat industry is mainly oriented toward cheese manufacturing, MFD can elicit economic losses. There is large individual variation in animal susceptibility with goats more (RESPO+) or less (RESPO-) responsive to diet-induced MFD. Thus, we used RNA-Seq to examine gene expression profiles in mammary cells to elucidate mechanisms underlying MFD in goats and individual variation in the extent of diet-induced MFD. Differentially expression analyses (DEA) and weighted gene co-expression network analysis (WGCNA) of RNA-Seq data were used to study milk somatic cell transcriptome changes in goats consuming a diet supplemented with marine lipids. There were 45 differentially expressed genes (DEGs) between control (no-MFD, before diet-induced MFD) and MFD, and 18 between RESPO+ and RESPO-. Biological processes and pathways such as "RNA transcription" and "Chromatin modifying enzymes" were downregulated in MFD compared with controls. Regarding susceptibility to diet-induced MFD, we identified the "Triglyceride Biosynthesis" pathway upregulated in RESPO- goats. The WGCNA approach identified 9 significant functional modules related to milk fat production and one module to the fat yield decrease in diet-induced MFD. The onset of MFD in dairy goats is influenced by the downregulation of SREBF1, other transcription factors and chromatin-modifying enzymes. A list of DEGs between RESPO+ and RESPO- goats (e.g., DBI and GPD1), and a co-related gene network linked to the decrease in milk fat (ABCD3, FABP3, and PLIN2) was uncovered. Results suggest that alterations in fatty acid transport may play an important role in determining individual variation. These candidate genes should be further investigated.

Microbiota-host crosstalk in the newborn and adult rumen at single-cell resolution

BackgroundThe rumen is the hallmark organ of ruminants, playing a vital role in their nutrition and providing products for humans. In newborn suckling ruminants milk bypasses the rumen, while in adults this first chamber of the forestomach has developed to become the principal site of microbial fermentation of plant fibers. With the advent of single-cell transcriptomics, it is now possible to study the underlying cell composition of rumen tissues and investigate how this relates the development of mutualistic symbiosis between the rumen and its epithelium-attached microbes.ResultsWe constructed a comprehensive cell landscape of the rumen epithelium, based on single-cell RNA sequencing of 49,689 high-quality single cells from newborn and adult rumen tissues. Our single-cell analysis identified six immune cell subtypes and seventeen non-immune cell subtypes of the rumen. On performing cross-species analysis of orthologous genes expressed in epithelial cells of cattle rumen and the human stomach and skin, we observed that the species difference overrides any cross-species cell-type similarity. Comparing adult with newborn cattle samples, we found fewer epithelial cell subtypes and more abundant immune cells, dominated by T helper type 17 cells in the rumen tissue of adult cattle. In newborns, there were more fibroblasts and myofibroblasts, an IGFBP3+ epithelial cell subtype not seen in adults, while dendritic cells were the most prevalent immune cell subtype. Metabolism-related functions and the oxidation-reduction process were significantly upregulated in adult rumen epithelial cells. Using 16S rDNA sequencing, fluorescence in situ hybridization, and absolute quantitative real-time PCR, we found that epithelial Desulfovibrio was significantly enriched in the adult cattle. Integrating the microbiome and metabolome analysis of rumen tissues revealed a high co-occurrence probability of Desulfovibrio with pyridoxal in the adult cattle compared with newborn ones while the scRNA-seq data indicated a stronger ability of pyroxidal binding in the adult rumen epithelial cell subtypes. These findings indicate that Desulfovibrio and pyridoxal likely play important roles in maintaining redox balance in the adult rumen.ConclusionsOur integrated multi-omics analysis provides novel insights into rumen development and function and may facilitate the future precision improvement of rumen function and milk/meat production in cattle.

First Evidence of the Presence of the Causative Agent of Caseous Lymphadenitis-Corynebacterium pseudotuberculosis in Dairy Products Produced from the Milk of Small Ruminants.

This study focused on the detection and quantification of selected bacteria and on the presence of enterotoxin genes in milk and dairy products from sheep and goat farms in the Czech Republic using quantitative real-time PCR (qPCR) and multiplex PCR (PCR). The presence of Corynebacterium pseudotuberculosis (CP), Mycobacterium avium subsp. paratuberculosis (MAP), Listeria monocytogenes, Staphylococcus aureus, S. aureus enterotoxin genes and methicillin-resistant Staphylococcus aureus (MRSA) was determined in 18 milk samples, 28 fresh cheeses, 20 ripened cheeses and 14 yoghurts. The serological status of the herds in relation to CP and MAP was taken into account. The most frequently detected bacterium was S. aureus (48.8%), and subsequent PCR revealed 11 MRSA positive samples. The S. aureus enterotoxin genes seg, sei and sec were detected in two goat cheeses. Cheese samples showed a statistically higher risk of SA and MRSA occurrence. CP (8.8%) and MAP (13.8%) were detected by qPCR on two different seropositive farms. Cultivation of qPCR positive CP samples on agar plates supplemented with potassium tellurite showed the presence of viable bacterium. The results obtained confirmed the necessity of monitoring the infectious status of dairy animals and rapid diagnosis of bacterial pathogens in milk and dairy products.