Milk quality of Italian Mediterranean Buffalo as affected by Temperature-Humidity Index during late spring and summer

Eighteen Italian Mediterranean buffalo cows were subjected to fortnightly milk sampling from May to July 2022. Air temperature and relative humidity were monitored throughout the trial; temperature-humidity index (THI) was calculated and ranged from 69 to 79 so that 3 classes were set to study the effect of different THI on milk quality: THI less than 72 - THI < 72; THI ranging from 72 to 76 THI72-76, and THI over 76 - THI > 76. Individual milk samples from buffalo cows were analyzed for milk composition and coagulation traits, fatty acid and amino-acid composition, enzymatic and mineral profile. The THI > 76 class registered the highest lactose content and poorer milk clot characteristics in comparison with THI < 72. Exposure to THI over 76 resulted in increased contents of saturated and short- chain fatty acids in milk as well as in the highest values of atherogenic and thrombogenic indexes and the lowest essential amino-acid content. Moreover, the lowest value of Calcium, Copper and Selenium contents were found in the milk of buffalo cows exposed to THI over 72. Results confirm that Italian Mediterranean buffalo expresses a good level of thermo-tolerance, even though exposure to daily THI over 76 has a deleterious effect on some nutritional and technological properties of milk.

Effects of extended transition milk feeding on blood metabolites of female Holstein dairy calves at 3 weeks of age: a liquid chromatography with tandem mass spectrometry-based metabolomics approach

Transition milk (TRM) is a rich source of bioactive components that promotes intestinal development and growth, and reduces the susceptibility to diarrhoea in calves. The objective of this study was to characterise the effects of replacing pasteurised waste milk (none-saleable milk containing antibiotic and/or drug residues) with pasteurised TRM for 3 wk on blood metabolites of dairy calves at 21 d of age. A total of 84 healthy newborn female Holstein calves was blocked by birth order and assigned randomly to four treatment groups with partial replacement of pasteurised waste milk by TRM (second milking after parturition) at 0 (0 L/day TRM + 6 L/day milk), 0.5 (0.5 L/day TRM + 5.5 L/day milk), 1 (1 L/day TRM + 5 L/day milk), or 2 L (2 L/day TRM + 4 L/day milk) for a 21-day period. Serum metabolome was determined by liquid chromatography with tandem mass spectrometry-based metabolomics analysis on a subset of 26 randomly selected individuals from calves fed pasteurised waste milk (CON, 6 L/d milk; n = 13) or TRM (2 L/d TRM + 4 L/d milk; n = 13) at 21 d of age. The identified metabolites (194 out of 265) were categorised according to chemical class and the number of metabolites per class in the serum, amongst which glycerophospholipids 16% (n = 43), fatty acyls 7% (n = 19), organic acids 7% (n = 18), organic heterocyclic compounds 5% (n = 13), benzenoids 5% (n = 12), sphingolipids 5% (n = 12), organic oxygen compounds 4% (n = 11), and nucleic acids 3% (n = 9), were the predominant types. Significant differences in metabolites were determined by the volcano plot. Applying the volcano plot, only two metabolites (ceramide and phosphatidylserine) were significantly different between CON and TRM. Overall, our results suggested that prolonged TRM feeding for 3 wk had little effect on the serum metabolome of the dairy calves. We speculate that the potential effects of feeding TRM for 3 wk compared with waste milk were spatially limited to affect the composition of the local gut microbial community and the growth or function of the intestinal epithelium, not allowing detection of the likely effects in the serum through a metabolomic approach.

Feeding tannins to dairy cows in different seasons improves the oxidative status of blood plasma and the antioxidant capacity of cheese

The aim of the present study was to assess the dietary supplementation of tannins to grazing dairy cows in 2 seasons characterized by a good quality pasture (spring) or a poor-quality pasture (summer). The effects of dietary tannins were assessed on plasma antioxidant status and cytokines profile and on the antioxidant properties of cheese and cheese in vitro digestates. Fourteen lactating dairy cows were divided into 2 homogeneous groups (n = 7): a control group (CON), and an experimental group (TAN) receiving 150 g/head per day of tannins supplementation. The experiment was performed twice, in spring and in summer. The animals were free to graze on spontaneous pasture (spring) or on dry stubble (summer). Blood was sampled at the beginning (d 0), at the midpoint (d 11), and at the end (d 22) of the trial. Individual cheese was produced before the beginning (d -1) and at the end (d 22) of the trial from the milk collected from each cow. On blood plasma, the reactive oxygen metabolites (ROM), biological antioxidant potential (BAP), nonesterified fatty acids quantification, and cytokines profile in terms of IL-10, IL-8, IL-1β, and IFN-γ were determined. Data on ROM demonstrated that tannins supplementation lowered oxidative stress both in spring and in summer. Accordingly, TAN diet increased BAP levels compared with the CON during summer trial. Thus, feeding tannins resulted in lower ratio between ROM and BAP (oxidative stress index) in both spring and summer. Cytokines' profile showed lower IL-1β values in TAN group at d 22 during spring season, with a concomitant higher IL-10 level, during summer season. Moreover, TAN group had a lower level of IFN-γ in plasma than CON group, both in spring and in summer. On cheese samples, the in vitro digestion was performed and on cheese and cheese digestates (gastric and intestinal digestate) the free radical scavenging antioxidant activity was evaluated. The intestinal digestate fraction registered the highest antioxidant activity compared with cheese and gastric digestate, in both spring and summer seasons. Furthermore, an improvement of the antioxidant property of cheese and cheese digestates was found. Present data demonstrated that tannins supplementation contributed to reduce the oxidative stress of lactating dairy cows and showed an increase of anti-inflammatory cytokines ratio.

Green extraction of bioactive compounds from wine lees and their bio-responses on immune modulation using in vitro sheep model

The objective of this study was to apply microwave-assisted extraction using green solvents starting from 3 different wine (white, rosé, and red) lees and to test their bio-response on sheep peripheral blood mononuclear cells proliferation, Bax/Bcl-2 ratio, and cytokines secretion. Wine lees (WL) of local organic farming from white wine, produced with Trebbiano cultivar, rosé and red wine, made with Nero di Troia cultivar, were collected. The WL were subjected to microwave-assisted extraction using 2 green solvents (water and ethanol) in 3 different combinations (water; water/ethanol 1:1 vol/vol; ethanol) with a dry matter-to-solvent ratio of 1:40 (wt/vol) at 4 temperature levels: 50, 100, 150, and 200°C. Sodium carbonate Na₂CO₃ (2 mmol/g of dry weight of lees) was used for increasing the polyphenol extraction yield. A total number of 6 extracts, 2 for each kind of WL investigated, according to their total phenolic content and in vitro antioxidant capacity, were selected to be tested on sheep peripheral blood mononuclear cells, as an animal model. All the WL extracts demonstrated a strong antiproliferative action. On the contrary, the cytokines' profile was mainly dependent on the different winemaking derived WL and the extraction solvent combination procedures. Red WL extract obtained by a combination of water/Na₂CO₃ and tested at 0.8 mg/mL, resulted in an increase of both IL-6 secretion and Bax/Bcl-2 ratio. Data from the present study demonstrated that WL extracts derived from different winemaking and solvent extraction could have a bimodal action on control of inflammatory mediated damage and highlighted the importance for further studies aimed at applying the biorefinery process on by-products to increase their economic value and exploit new derived bioactive compound.

Milk nutrition and childhood epilepsy: An ex vivo study on cytokines and oxidative stress in response to milk protein fractions

We present a pilot study on the effects of milk protein fractions [α_S1-casein (CN), α_S2-CN, κ-CN, β-CN, and a mix of α-lactalbumin (α-LA) and β-lactoglobulin (β-LG)] from different animal species (bovine, ovine, and caprine) on pro- and anti-inflammatory cytokines and oxidative status in cultured peripheral blood mononuclear cells from children with generalized epilepsy. Peripheral blood mononuclear cells (PBMC) were obtained by density gradient from blood of 10 children with generalized epilepsy (5 males; mean age 33.6 ± 5.4 mo) and 10 controls (5 males; mean age 35.6 ± 6.8 mo). Children with epilepsy were grouped according to cytokine levels as follows: children with epilepsy having low levels of cytokines not different from those of control children (LL-EC); children with epilepsy having cytokine levels at least 5-fold higher (medium levels) than those of control children (ML-EC); and children with epilepsy having cytokine levels at least 10-fold higher (high levels) than those of control children (HL-EC). The production of tumor necrosis factor-α (TNF-α), IL-10, IL-6, and IL-1β was studied in cultured PBMC incubated with α_S1-CN, α_S2-CN, κ-CN, β-CN, and a mix of α-LA and β-LG from bovine, caprine, and ovine milks. The levels of reactive oxygen and nitrogen species (ROS/RNS) and catalase activity were assessed in cultured supernatant. In the HL-EC group, β-CN from small ruminant species (ovine and caprine) induced the highest levels of TNF-α, whereas PBMC incubated with α_S2-CN from ovine milk and the mix of β-LG and α-LA from all tested milk species had the lowest levels of TNF-α. Within the HL-EC group, production of IL-1β was higher for bovine and ovine α_S2-CN fractions and lower for caprine and ovine β-CN and κ-CN. In the HL-EC group, IL-6 was higher in cultured PBMC incubated with α_S2-CN from bovine and ovine milk than from caprine milk. The cytokine IL-10 did not differ among milking species. The highest levels of ROS/RNS were found after incubation of PBMC with the β-CN fraction in bovine milk. Catalase activity was higher in PBMC cultured with β-CN isolated from bovine and caprine milk and with α_S1-CN from ovine milk.

Peripheral blood mononuclear cell proliferation and cytokine production in sheep as affected by cortisol level and duration of stress

A large number of studies recognize glucocorticoids (Gc) as suppressors of inflammation; Gc exert an important role in coordinating the magnitude and duration of host immune responses. In the present in vitro investigation, we tested incremental levels of cortisol to verify the immunosuppressive or immunopermissive role of cortisol in sheep peripheral blood mononuclear cells (PBMC) after acute and chronic stress. Phytohemagglutinin (PHA)-stimulated PBMC were cultured for 24h and 96h at 37°C with 5% of CO₂ and varying cortisol levels: 10 ng/mL (baseline), 100 ng/mL (physiological poststressor), and 1,000 ng/mL [hyperactivated hypothalamic-pituitary-adrenal (HPA) axis]. The cell-free supernatants were collected for determination of IL-6, IL-1β, and IL-10 by ELISA, and the bromodeoxyuridine assay was performed on cells. Physiological cortisol concentration negatively affected the levels of IL-6 secreted by PBMC, resulting in increased cell proliferation after acute stress (24h of incubation). However, physiological cortisol concentration exhibited a reduction in cell proliferation induced by increased levels of IL-6 secreted by PBMC during chronic stress (96h of incubation). The cortisol concentration representing a hyperactivated HPA axis led to a reduction in cell proliferation after acute stress, which was probably induced by the elevated IL-10 production. Our results demonstrate that in sheep the effect of Gc on the immune system was related to the magnitude and the duration of stress. In particular, cortisol levels higher than physiological concentrations suppressed cell proliferation soon after acute stress. Instead, the physiological poststressor concentration of cortisol affected the immune responses in a bidirectional manner depending on the duration of the stressor.

Milk from different species: Relationship between protein fractions and inflammatory response in infants affected by generalized epilepsy

The present study was undertaken to evaluate the effect of protein fractions from bovine, caprine, and ovine milk on production of cytokines and reactive oxygen species (ROS) and reactive nitrogen species (RNS) by cultured peripheral blood mononuclear cells (PMBC) from infants with generalized epilepsy. Bovine, caprine, and ovine bulk milks were pasteurized and analyzed for chemical composition. Then, PBMC were isolated from 10 patients with generalized epilepsy (5 males; mean age 33.6±5.4mo). Production of tumor necrosis factor-α (TNF-α), IL-10, IL-6, and IL-1β was studied in cultured PBMC (from infants with epilepsy and controls) stimulated by bovine, caprine, and ovine milk and casein and whey protein fractions, and levels of ROS and RNS were measured in the culture supernatant. The ability of PBMC to secrete cytokines in response to milk and protein fraction stimulation may predict the secretion of soluble factor TNF-α in the bloodstream of challenged patients. Bovine, caprine, and ovine bulk milks induced low-level production of IL-10 by cultured PBMC in at least 50% of cases; the same behavior was observed in both casein and whey protein fractions for all species studied. Bovine and ovine milk and their casein fractions induced production of lower levels of IL-1β in 80% of patients, whereas caprine milk and its casein fraction induced the highest levels in 80% of patients. The amount of IL-6 detected after stimulation of PBMC by milk and its fractions for all species was lower than that of other proinflammatory cytokines. In the bovine, total free radicals were higher in bulk milk and lower in the casein fraction, whereas the whey protein fraction showed an intermediate level; in caprine, ROS/RNS levels were not different among milk fractions, whereas ovine had higher levels for bulk milk and casein than the whey protein fraction. Lower levels of ROS/RNS detected in PBMC cultured with caprine milk fraction could be responsible for the lower levels of TNF-α cytokine in the corresponding fraction. Cytokines might be useful biomarkers to discriminate the effects of foods on the inflammatory response; dietary strategies could help in alleviating the negative effects of epilepsy in infants.

Hypothalamic-pituitary-adrenal axis activation and immune regulation in heat-stressed sheep after supplementation with polyunsaturated fatty acids

The aim of this study was to assess the effects of supplementation with polyunsaturated fatty acids from different sources on immune regulation and hypothalamic-pituitary-adrenal (HPA) axis activation in heat-stressed sheep. The experiment was carried out during the summer 2012. Thirty-two Comisana ewes were divided into 4 groups (8 sheep/group): (1) supplemented with whole flaxseed (FS); (2) supplemented with Ascophyllum nodosum (AG); (3) supplemented with a combination of flaxseed and A. nodosum (FS+AG); and (4) control (C; no supplementation). On d 22 of the experiment, cortisol concentrations in sheep blood were measured after an injection of ACTH. Cellular immune response was evaluated by intradermic injection of phytohemagglutinin (PHA) at 0, 15, and 30 d of the trial. Humoral response to ovalbumin (OVA) was measured at 0, 15, and 30 d. At 0, 15, and 30 d of the experiment, blood samples were collected from each ewe to determine production of T-helper (Th)1 cytokines (IL-12 and IFN-γ), and Th2 cytokines (IL-10, IL-4, IL-13), and concentrations of heat shock proteins (HSP) 70 and 90. Ewes supplemented with flaxseed alone had greater cortisol concentrations and a longer-lasting cell-mediated immune response compared with ewes in the control and other groups. Anti-OVA IgG concentrations increased in all groups throughout the trial, even though ewes in the FS+AG group had the lowest anti-OVA IgG concentrations at 15 d. The level of IL-10 increased in all groups throughout the experiment; the FS+AG group had the lowest IL-13 concentration at 15 and 30 d. The concentration of HSP 70 increased in AG ewes at the end of the experiment and decreased in FS ewes, whereas that of HSP 90 increased in FS ewes compared with FS+AG ewes. Flaxseed supplementation was found to influence in vivo HPA activation in heat-stressed sheep, resulting in increased cortisol concentrations, probably to meet increased energy demand for thermoregulation. Flaxseed supplementation also supported Th1 response via a complex cross-talk between IL-10, IL-12, and IFN-γ production.