Association between non-esterified fatty acids and calcium concentrations at calving with early lactation clinical diseases, fertility and culling in grazing dairy cows in Uruguay.

This study describes the association of non-esterified fatty acids (NEFA) and calcium concentrations at calving with early lactation disease, reproductive performance and culling in 646 dairy cows from 13 commercial grazing dairy herds in Uruguay. During one year, health events were recorded from calving to 30 days in milk (DIM). The first author visited each farm every 20 days. During each visit, body condition score (BCS) was recorded (scale 1-5), defining BCS < 3 as suboptimal and BCS > 3 as optimal, and a blood sample was taken from cows between 0 and 4 DIM for metabolite determination. To evaluate the association between health events (i.e., retained placenta-metritis and clinical mastitis) and risk factors (parity, BCS, high NEFA (> 0.6 mmol/L) and subclinical hypocalcemia (SCH) (< 2.10 mM)) data were analysed using multivariable logistic regression models. To evaluate the association of health events and risk factors with reproductive performance and culling, data were analysed using Cox proportional hazard regression models. A risk factor and an outcome of interest were assumed to be associated at P < 0.05 and a tendency to be associated was defined at P < 0.10. Overall, 47 % (n = 303) of the cows showed elevated NEFA concentration and 77 % (n = 499) had SCH. In addition, 21.5 % (n = 139) of the cows recorded at least one clinical disease. Cumulative incidence was 17 % (n = 109) for clinical mastitis, 4.2 % (n = 27) for retained placenta (RP)-metritis and 1.4 % (n = 7) for lameness. Clinical mastitis was associated with parity, with lower odds in primiparous (PP) cows (OR = 0.42, P < 0.01). Cows in an optimal BCS also tended to have lower odds (OR = 0.66, P = 0.07). Moreover, high NEFA and SCH cows had higher odds of CM (OR = 4.5, P = 0.01 and OR = 1.75, P = 0.04, respectively). Retained placenta-metritis tended to be associated with high NEFA concentration (OR = 2.2, P = 0.06). Primiparous cows with suboptimal BCS showed an increased first insemination rate (HR = 2.34; P < 0.01). The risk of culling was lower in PP cows (HR = 0.19; P < 0.01) and in cows with optimal BCS and low NEFA concentration (HR = 0.38; P = 0.03). Our data show that metabolic challenge (defined as peripartum suboptimal BCS, high NEFA or SCH) is associated with increased odds of clinical mastitis and RP-metritis, decreased probability of insemination and increased hazard of culling. Under grazing conditions, we suggest that farm management to improve the metabolic adaptation to lactation represents an opportunity to enhance cow performance in terms of health, fertility and longevity.

Effect of recombinant bovine granulocyte colony-stimulating factor treatment during the peripartum period on postpartum diseases, reproductive performance, and milk production in Holstein cattle.

To boost the immune function around parturition, recombinant bovine granulocyte colony-stimulating factor (rbG-CSF) has been used to increase the number of neutrophils. Therefore, the aim of this study was to quantify the effect of rbG-CSF administration on the incidence of postpartum pathologies, reproductive performance, and milk production during the first three months of lactation. A total of 199 Holstein cows from one herd were included and were randomly allocated into two groups: Control (n = 103) and rbG-CSF (n = 96). Cows in the rbG-CSF group received 2 doses of a rbG-CSF injectable formulation, one 7 days before the expected date of calving and the other within 24 h after calving. For 6 weeks following calving, animals were examined weekly to assess the presence of postpartum pathologies. Milk production, protein and fat content, and somatic cell count were determined monthly by the regional dairy herd improvement association. Data about the reproductive performance were collected from on-farm software. To analyse the effect of treatment on the incidence of postpartum pathologies, Pearson's χ2 test and multivariable logistic regressions were performed. The effect on reproductive performance was analysed using Cox proportional hazard regression analysis for days open, binary logistic regression for first service conception rate and Oneway ANOVA test for the number of artificial inseminations. The effects of treatment on milk yield and milk composition were checked using GLM repeated measures analysis. No statistically significant differences were observed between treatment groups for any of the parameters evaluated. Only parity had a significant effect on days open and milk production (p < 0.05). In conclusion, in the present study no evidence was found that rbG-CSF could have an effect on the reproductive and productive parameters evaluated.

Stability study of ptaquiloside biotoxin from P. esculentum var. Arachnoideum in bovine milk and artisanal dairy-food products.

The potential health risk of consuming dairy products made from milk processed in an artisanal manner was investigated due to possible contamination with Ptaquiloside (PTA), a carcinogenic compound found in the food chain of the bracken fern. The study aimed to assess the occurrence and stability of PTA across various processing stages, including pasteurization, cheese production, and yogurt production. Results indicated that pasteurization effectively converted all PTA to Pterosin (PTB), with PTB levels decreasing during refrigerated storage for up to two weeks. The stability and occurrence of initial PTA contamination remained unchanged in yogurt production. Biotoxin concentrations in soft cheeses decreased over time, independent of ionic strength; cheeses with low salt concentrations showed lower retention of the biotoxin within the cheese protein network. These findings offer valuable insights into the stability and occurrence of PTA, facilitating the monitoring and identification of potential adverse health effects.

Pinhão potential and their parts (failures, shells, and almonds) in the elaboration of yogurts containing acai pulp: physicochemical, nutritional, and functional properties, antimicrobial activity, and multi-elemental profile.

This study applies natural resources, prioritizing recyclable and renewable inputs produced by pinhão cultivation, whose purpose is to use the failures, shells, and almonds as a source of bioactive compounds addition in yogurt, ensuring intelligent use of these natural resources. Thus, one açaí yogurt sample and eight yogurt formulations containing portions of pinhão byproducts between 5 % and 10 % were elaborated. These formulations were compared regarding their physicochemical, nutritional, functional properties, antimicrobial activity, and multi-elemental profile properties. Enriching açaí yogurt with pinhão byproducts does not significantly differ in protein, lipid, moisture, and mineral salt content between all samples with pinhão byproducts. Açaí yogurts enriched with pinhão byproducts had 5.71 to 26.07 % times total protein than the control sample, and total fiber also had a significant increase in samples ranging between 18.62 to 85.29 % times more than the control sample. Regarding color settings, all yogurt samples tended to be red-purple. A sample of açaí yogurt with pine nut flour and whole pine nut flour caused a biofilm mass amount of 46.58, 45.55, and 11.85 % for Listeria monocytogenes, Salmonella enteritidis and Pseudomonas aeruginosa. The behavior of pathogenic bacteria is related to the total polyphenol content in yogurts enriched with pinhão byproducts, which increased from 8.27 to 18.24 mg/100 g. Yogurt with açaí enriched with whole pinhão flour showed high antioxidant capacity. The sample's antioxidant activity results increased by 47.62 % and 130.38 % in the ABTS and DPPH analyses, respectively. The compounds in pinhão failure nanosuspensions, pinhão flour, whole pinhão flour, and yogurts were identified and divided into hydrophilic and lipophilic classes. Five classes (amino acids, organic acids, sugars, phenols, and cyclitols) were identified as hydrophilic. Lipophilic compounds were identified and separated into six classes (carboxylic acids, diterpenes, alcohols, Α-hydroxy acids, sterols, and triterpenes). The addition of pinhão byproducts increased the contents of Ca, Fe, K, Na, and P. Açaí yogurt with pinhão nanosuspension, pinhão flour, and whole pinhão flour had the highest Ca content (2164.38 ± 2.16 µg/L). Açaí yogurt with pinhão flour and whole pinhão flour had the highest Fe content (84.02 ± 0.08 µg/L).

Determining nine fasciolicides and three metabolite residues in milk and infant formula using solid-phase extraction and liquid chromatography-tandem mass spectrometry.

A new sensitive method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis for nine fasciolicides (closantel, rafoxanide, oxyclozanide, niclosamide, nitroxinil, ioxynil, 4-nitro-3-(trifluoromethyl)phenol, salicylanilide, and triclabendazole) and three metabolite residues (ketotriclabnedazole, triclabendazole sulfone, and triclabendazole sulfoxide) in milk and infant formula was established. The samples were extracted and purified through solid-phase extraction and analyzed using LC-MS/MS. The proposed method demonstrated high accuracy (the average recoveries ranged from 70.5 % to 107.4 %) and high sensitivity (the limits of quantification ranged from 1.0 to 25.0 µg/kg). This method was successfully applied to determine nine fasciolicides and three metabolite residues in 45 milk and infant formula, providing technical support for the safety and quality evaluation of dairy products.

Effect of oregano essential oil on intestinal immunoglobulin G in Holstein dairy bulls.

Introduction: Immunoglobulin G (IgG) is important in mediating humoral immunity and in the maintenance of immune homeostasis in the intestinal mucosa. Oregano essential oil (OEO) is a natural herbal extract that possesses antimicrobial, antioxidant, anti-inflammatory, and immunomodulatory properties. As the effects of OEO on intestinal mucosal immunity in Holstein dairy bulls remained unclear, we investigated the effect of dietary supplementation of OEO on IgG levels and IgG+ cells residing in the intestinal tract in Holstein dairy bulls. Methods: Twelve Holstein bulls in good health of approximately 10 months of age were selected for the experiment and randomly equally divided into two groups. The control (CK) group was fed a basal ration, and in the OEO group, the basal ration was supplemented with OEO (20 g/head/day). After 300 days of feeding, tissue samples of the jejunum, ileum, and colon of the bulls in each group were collected for histopathological analysis, immunohistochemistry, and enzyme-linked immunosorbent assays, respectively. Results: The jejunum, ileum, and colon of bulls in the CK group had obvious pathological damage, whereas the structure of each intestinal segment was clear and intact. In the OEO group, pathological damage was significantly reduced. IgG+ plasma cells were diffusely distributed in the lamina propria of the jejunum, ileum, and colon in the CK and OEO groups, with no significant difference between the groups. OEO supplementation significantly reduced the number of IgG+ plasma cells in each intestinal segment, with the highest decrease rate being noted for the ileum (22.87%), followed by the colon (19.45%) and jejunum (8.52%). ELISA test results and immunohistochemical results were mutually verified. The change in IgG content was consistent with the trend of change in the number of IgG+ plasma cells. Discussion: Our findings suggest that OEO supplementation does not alter the diffuse spatial distribution of IgG+ plasma cells in the intestines of Holstein dairy bulls, but lowers immunoglobulin levels to normal levels, significantly reduces intestinal damage, and may enhance mucosal immune defence barrier function by inhibiting inflammatory reactions.

Evaluation of raw milk samples and vendor-derived Staphylococcus aureus and Coxiella burnetii prevalence in dairy delicatessens in eastern Turkey.

This study investigated the prevalence, antimicrobial resistance, and genetic diversity of Staphylococcus aureus, as well as the detection and genetic relationship of Coxiella burnetii in retail milk samples and plastic bags from 25 local dairy delicatessens. Bacteriological culture, PCR, and Sanger sequencing were performed. Eleven percent of the samples were positive for S. aureus, none of which were methicillin-resistant or enterotoxigenic. The rep-PCR analysis revealed a high similarity between strains isolated from milk and bag samples from the same source. Moreover, 14% of the milk samples were positive for C. burnetii, which matched 100% of the reference strains in the GenBank.

Dairy intake screener as web-based application is reliable and valid.

The "Dairy Diary" is a user-friendly web-based dairy intake screener. The reliability and validity are unknown. We aimed to evaluate the screener in terms of test-retest reliability and comparative validity. In a diagnostic accuracy study, a purposefully recruited sample of 79 (age: 21.6 ± 3.8 years) undergraduate dietetics/nutrition students from three South African universities completed 3 non-consecutive days of weighed food records (reference standard) within a seven-day period (comparative validity), followed by two administrations, 2 weeks apart, of the screener (index test) (reliability). For the four dairy product serving scores (PSSs) and the summative dairy serving scores (DSSs) of the screener and the food records, t-tests, correlations, Bland-Altman, Kappa, McNemar's, and diagnostic accuracy were determined. For reliability, mean PSSs and DSSs did not differ significantly (p > .05) between the screener administrations. The mean PSSs were strongly correlated: milk (r = .69; p < .001), maas (fermented milk) (r = .72; p < .001), yoghurt (r = .71; p < .001), cheese (r = .74; p < .001). For DSSs, Kappa was moderate (k = 0.45; p < .001). Non-agreeing responses suggest symmetry (p = .334). For validity, the PSSs of the screener and food records were moderately correlated [milk (r = .30; p = .0129), yoghurt (r = .38; p < .001), cheese (r = .38; p < .001)], with k = 0.31 (p = .006) for DSS. Bland-Altman analyses showed acceptable agreement for DSSs (bias: -0.49; 95% CI: -0.7 to -0.3). Categorized DSSs had high sensitivity (81.4%) and positive predictive value (93.4%), yet low specificity (55.6%) and negative predictive value (27.8%). The area under the receiver operating characteristic curve (0.7) was acceptable. The "Dairy Diary" is test-retest reliable with moderate comparative validity to screen for dairy intake of nutrition-literate consumers.

Optimization of citrus fiber-enriched vegan cream cheese alternative and its influence on chemical, physical, and sensory properties.

Dairy product alternatives have increased in recent years as a result of medical prescriptions or personal preferences. The main purpose of the present study was to optimize vegan-based cream cheese formulation added with citrus fiber considering the textural and physicochemical properties of the samples. The physicochemical (pH value, water activity, and color), texture, microstructure, and sensory properties of manufactured vegan-based cream cheese were characterized and compared to those of a commercial one. Three optimized products were produced, according to the textural properties. The addition of citrus fiber did not affect the pH and water activity values of the cheese samples significantly. Although citrus fiber had an effect on the color values of the samples, a significant difference in the sensory scores was not recorded by the panelists. The sample having 1.21% citrus fiber (A) showed a hardness value similar to that of control sample and it received high sensory appreciation. The sample added with 1.41% citrus fiber (B) was scored high by the panelists, with no significant difference compared to commercial cream cheese, even though it showed high hardness. According to the results of the current research, vegan-based cream cheese can be produced as a promising food as a new alternative to milk and dairy products.

Nanoemulsions of red quinoa and ginseng extracts with chitosan wall: Investigating the antioxidant properties and its effect on the shelf life of dairy cream.

The study aimed to investigate the antioxidant properties of ginseng and red quinoa extract nanoemulsion and its effect on the shelf life of dairy cream. Nanoemulsion includes dairy cream, Tween 80, chitosan, whey protein powder, chitosan/whey protein powder, red quinoa extract, ginseng extract, and a mixture of extracts (1:1). The highest total phenol content and total flavonoid content were related to ginseng extract (24,009.55 mg of gallic acid equivalent/kg, 883.16 mg quercetin/kg) with ethanol-water solvent (80:20). Most of the phenolic and flavonoid compounds of ginseng and red quinoa extracts were related to p-coumaric acid (211.3 µg/g), catechin (29.6 µg/g), ellagic acid (73.88 µg/g), and rutin (34.12 µg/g), respectively. Considerable antioxidant power in the concentration of 800 ppm of red quinoa and ginseng extracts (ethanol-water solvent (50:50), (80:20)) in 2,2-diphenyl-1-picrylhydrazyl radical scavenging (80%, 82%, 80%, and 78%), bleaching ß-carotene: linoleic acid (81%, 73%, 77%, and 86%), and ferric reducing antioxidant power assays (70%, 73%, 72%, and 76%) was observed. Nanoemulsions of red quinoa extract with chitosan wall had the smallest particle size (250.67 nm), the highest encapsulation efficiency (72.79%), and the polydispersity index (0.34). Nanoemulsions containing ginseng + quinoa (1:1) with chitosan/whey protein powder wall showed the highest viscosity (5.30 mPa/s) and the mostzeta potential (-32.6 mv). Also, nanoemulsions of red quinoa extract showed the lowest amount of peroxide value and the thiobarbituric acid value (12 milliequivalent O2/kg-0.48 µg/mL) in dairy cream oil. In general, the red quinoa extract with chitosan wall was superior to other samples due to the delay in oxidation and positive effect on the shelf life of dairy cream.

Respiratory illness in young and adult cattle caused by bovine viral diarrhea virus subgenotype 2b in singular and mixed bacterial infection in a BVDV-vaccinated dairy herd.

Bovine respiratory disease (BRD) is a common global health problem in dairy cattle. The definitive diagnosis of BRD is complex because its etiology involves several predisposing and determining factors. This report describes the etiology of a BRD outbreak in a dairy herd in the mesoregion of Central Eastern Paraná, which simultaneously affected young (calves and heifers) and adult (cows) Holstein-Friesian cattle. Nine biological samples, consisting of five lung samples from two cows and three suckling calves, and four nasal swab samples from heifers, were used for etiological diagnosis. The nucleic acids extracted from lung fragments and nasal swabs were subjected to PCR and RT-PCR assays for partial amplification of the genes of five viruses [bovine viral diarrhea virus (BVDV), bovine alphaherpesvirus 1 (BoAHV1), bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus 3 (BPIV-3), and bovine coronavirus (BCoV)] and four bacteria (Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni) involved in the etiology of BRD. All nine biological samples from the animals with BRD tested negative for BoAHV1, BRSV, BPIV-3, BCoV, and H. somni. Therefore, the involvement of these microorganisms in the etiology of BRD outbreak can be ruled out. It was possible to identify the presence of BVDV and M. bovis in singular and mixed infections of the lower respiratory tract in cattle. BVDV was also identified in two nasal swabs: one as a single etiological agent and the other in association with two bacteria (P. multocida and M. haemolytica). The phylogenetic analysis conducted in the nucleotide sequence of the 5'UTR region and Npro gene of the BVDV amplicons demonstrated that the BVDV field strains of this BRD outbreak belong to subgenotype 2b. To the best of our knowledge, this is the first report of BVDV-2b involvement in the etiology of BRD in Brazil. Finally, it is necessary to highlight that the cattle were obtained from an open dairy herd with biannual vaccinations for BVDV-1a and - 2a.

Application of type I and II error analysis to support economic decision-making of using an immunomodulator feed additive.

The use of the immunomodulator OmniGen- AF® (OMN) feed supplement, where the response in milk yield, health, and reproduction is uncertain, allows for an application of type I (use the product when it is not profitable) and type II (do not use the product when it is profitable) analysis to aid decision making regarding its profitability. This study applies a type I and II error analysis to quantify the economic risk of investing in OMN feed supplementation using data from a controlled study and a field data set collected on dairy farms. Four prediction models were applied considering the expected value and standard deviation of the response in milk yield; milk and health; milk and reproduction; milk, health, and reproduction. Uncertainty in the milk response was modeled following a normal distribution with mean 0.15 kg/cow/d and standard deviation 0.81 kg/cow/d. This distribution was left-truncated at 0 kg, which resulted in a mean (expected) response of 0.7 kg/cow/d. Based on the field data set, the reduction in health costs and reproduction were estimated at $0.086 and $0.33/cow/day. All 3 responses were assumed to be present or not in the first 90 DIM. The increase in milk yields necessary to pay for the OMN supplementation considering a response in milk yield only, milk and health, milk and reproduction, and milk, health, and reproduction were 0.45, 0.19, -0.56, and -0.82 kg/cow/d respectively. The break-even OMN cost per cow per day when considering the increases in milk yield, milk and health, and milk and reproduction, milk, health, and reproduction were $0.23, $0.31, $0.56, and $0.65 respectively. Production responses resulted in costs exceeding revenue with a type I error cost of $2.62 for milk and $0.47 for milk and health response for the broke even. There was no type I error cost associated when considering the responses in milk and reproduction, and the combination of milk, health and reproduction which implies that there is no risk of using OMN when it is not profitable ( = the product is profitable for certain). Type II costs were associated with returns that are unrealized because of failing to use OMN when it is profitable with an opportunity cost of $9.92, $15.53, $37.23, and $45.08 per cow per day for the responses in milk yield; milk and health; milk and reproduction; and milk, health, and reproduction respectively. We concluded that a type I and II error analysis applied to the use of the OMN feed additive provided additional insights beyond a break-even analysis to support economic decision-making when the response on dairy farms is uncertain. The type I and II error analysis can aid in decision-making process to evaluate the adoption of a new technology.

The economic effect of cow-based reproductive management programs with a systematic use of reproductive hormones.

Hormone-based reproductive management programs can be beneficial to improve dairy cow's reproductive performance. This study aimed to compare the economic impact of reproductive management programs using systematic hormonal treatments to individual cows with a specific DIM range with a reproductive management program using cow-specific hormonal treatment based on a veterinary diagnosis of ovarian dysfunction during a fertility check. An existing individual cow-based, dynamic, and stochastic bio-economic simulation model, mimicking the production dynamics of a 200 cow-herd in daily time steps, was extended with ovarian dysfunction and fertility inputs. Four hormone-based reproductive management programs were modeled. In the default reproductive management program, reflecting the current reproductive management of Dutch herds, lactating dairy cows are inseminated based on detection of estrus and non-cyclic dairy cows are treated with hormones based on a veterinary diagnosis of ovarian dysfunction during a fertility check. Hormone treatments prescribed by the veterinarian for anestrus, cystic, and sub-estrus cows were an 8-d progesterone-releasing intravaginal device (PRID)-Synch protocol (PRIDsynch), an Ovsynch protocol, and a PGF2⍺ treatment, respectively. The 3 other reproductive management programs reflected systematic hormonal treatments to cows at specific DIM and included a 1) Double-Ovsynch protocol for TAI with nonpregnant cows submitted to a resynchronization protocol (FTAI), 2) Double-Ovsynch protocol for TAI with nonpregnant cows detected in estrus or submitted to a resynchronization protocol (FTAI+ED), and 3) detection of estrus with cows not detected submitted to a PRIDsynch protocol (ED+TAI). All nonpregnant cows were submitted to a resynchronization protocol based on the absence (PRIDsynch) or presence (Ovsynch protocol) of a corpus luteum (CL). The annual mean net economic return (NER) was calculated for all reproductive management programs. Compared with the default reproductive management program, the highest NER was observed for the FTAI+ED reproductive management program with €23,764 higher net revenues, followed by the FTAI and the ED+TAI reproductive management programs with €19,550 and €14,314 higher net revenues, respectively. Overall, systematic hormone-based reproductive management programs gave higher costs due to more hormones administered and higher calving and feed costs due to more pregnant cows. Nevertheless, the additional revenues of milk and calves in the systematic hormone-based reproductive management programs outweighed the total cost. For instance, the FTAI+ED reproductive management program gave €8,953 higher total cost per year compared with the default but with €32,654 higher revenues. In summary, reproductive management programs where hormones were systematically used gave economic advantages over the current default reproductive management program in which hormones are administered to individual cows based on a veterinary diagnosis of ovarian dysfunction during a fertility check.

Effectiveness of energy dispersive X-ray fluorescence for the quantification of mineral elements in skim milk and whey powders.

Milk and whey are subjected to quick deterioration due to bacterial growth. Turning them into powder allows for extended shelf life, easier storage, and more effective transport. Monitoring mineral elements in dairy powders is crucial for both technological and nutritional implications. Current analysis of minerals in food matrices is time consuming and requires high costs and labor. In this view, energy dispersive x-ray fluorescence (ED-XRF) may represent a potential alternative technique to rapidly determine mineral content of food matrices. The present study aimed to investigate the effectiveness of ED-XRF technique for the prediction of Na, Mg, P, S, K, Ca, Cu, and Zn in skim milk and whey powders. Reference analysis for mineral concentration in dairy powders was inductively coupled plasma optical emission spectrometry. The accuracy of ED-XRF for the prediction of mineral elements was assessed on all available samples (global calibration set; n = 23), and after splitting the whole data in a training set (n = 16) and a testing set (n = 7), comprising 70% and 30% of the available samples, respectively. The accuracy of prediction was moderate to low for Na and Mg, whereas robust predictions were obtained for P, S, K, Ca, Cu, and Zn, with coefficients of determination in global calibration from 0.88 to 0.99, and ratios performance to deviation in testing from 2.14 to 24.74. Results suggest that ED-XRF can be considered for accurate prediction of main mineral elements in dairy powders.

Improving market (cull) dairy cows carcass traits and meat quality.

Despite a high volume of market (cull) dairy cows entering the food chain every year, beef from market dairy cows is largely considered insignificant when compared with beef from beef cattle in the market and is widely thought to be used for ground beef only. Our study aimed to evaluate the effects of feeding dairy market cows on a lactating TMR diet before slaughter on carcass and beef quality traits. Forty-three Holstein market cows were randomly assigned into 2 treatments: Fed or Direct. Fed cows (n = 22) were dried off, then fed a lactating cow TMR ration for approximately 60 d whereas Direct cows (n = 21) were sent directly to slaughter. Hot carcass weight (HCW) was used to calculate the dressing percentage (DP) together with the animals' body weight recorded when animals left the farm to go to the abattoir. At 24h post-mortem, the rib fat thickness (RFT) and rib eye area (REA) were measured by a certified grader. Afterward, rib samples were collected between the 12th -10th ribs from one side of the carcass and divided into 5 ribeye steaks. The first steak was used for intramuscular fat (IMF) content analysis by NIRS. The other 4 steaks were then aged for 7, 14, 21, or 28 d. Following aging, the steaks available were assessed for tenderness using the Warner-Bratzler Shear Force protocol. Data were analyzed by mixed linear regression to compare experimental groups for continuous outcomes. HCW of the Fed cows was higher than the Direct cows, with a mean HCW of 408.3 kg and 326.1 kg, respectively (SE ± 9.0). Average DP in Fed cows was 49.1%, compared with 42.5% in Direct cows (SE ± 0.69). The average percentage of IMF in Fed cows was 8.1% and in Direct cows was 5.0% (SE ± 0.43). Fed cows had a mean REA of 68.1 cm2 and Direct cows had a mean of 57.7 cm2 (SE ± 11.9). No differences were found for RFT. The steaks aged for 14 d resulted in meat with a mean shear force (SF) of 4.19 kg in Fed cows, while Direct cows had a mean SF of 6.28 kg (SE ± 0.29) Feeding market dairy cows for 60 d before slaughter enhanced carcass weight and yield, IMF content, and tenderness. These results indicate that approximately 60 d of feeding can improve the quality of market dairy cow meat and may help improve market cow value.

Association between calcium intake from different food sources during childhood and cardiometabolic risk on adolescence: The Generation XXI birth cohort.

BACKGROUND: Calcium intake has been associated with lower adiposity, but few studies explored the longitudinal relation of calcium from different sources and cardiometabolic markers in young population. OBJECTIVE: Prospectively estimate the association between dairy and non-dairy calcium intake at 4, 7, and 10 years (y) of age and cardiometabolic risk at 13 y. METHODS: The sample included 4017 participants from the Generation XXI birth cohort. Dietary data were collected from a 3-day food diary. Cardiometabolic clusters at 13 y were estimated by a probabilistic Gaussian mixture model (z-score of waist circumference [WC], HOMA-IR; HDL cholesterol, triglycerides, and systolic blood pressure [BP]). Multivariable linear and logistic regression models were used to estimate associations. RESULTS: Calcium intake (/100 mg), after adjustment for confounders, was negatively and significantly associated with body mass index (BMI) (ß = -0.02, 95% CI: -0.04; -0.01), WC (cm) (ß = -0.23, 95% CI: -0.36; -0.11), and diastolic BP (mmHg) (ß = -0.14, 95% CI: -0.26; -0.03). After additional adjustment for total energy intake, associations lose statistical significance. Calcium intake from milk at 7 y was inversely associated with WC (ß = -0.25, 95% CI: -0.48; -0.03) and from yogurt at 10 y was associated with higher BMI (ß = 0.08, 95% CI: 0.03; 0.13) and WC (ß = 0.54, 95% CI: 0.12; 0.96). Calcium from vegetables at 4, 7, 10 y reduces later cardiometabolic risk (OR = 0.71; OR = 0.84; OR = 0.98, respectively). CONCLUSIONS: This study supports a protective effect of calcium on adolescents' cardiometabolic health, especially from vegetables.

Heavy metals and trace elements in milk and dairy products in the Lazio region (Central Italy).

A study was carried out to determine the concentration of heavy metals and trace elements in milk and dairy products collected from local farms, supermarkets, or food retailers in the region of Lazio (Central Italy). Persistent exposure to metal contamination is of particular concern for human health, as it can cause different serious disorders. The monitoring of the matrices studied is therefore important, given their high consumption in the daily diet. The elements determined by ICP-MS (Inductively Coupled Plasma - Mass Spectrometry) were lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), chromium (Cr), nickel (Ni), molybdenum (Mo) and thallium (Tl), for a total of 151 measurements in 98 samples. The results showed that 11.3% of the measurements were quantifiable but below the legal maximum limits (MLs) set by EU regulations. The data obtained may be useful for dietary exposure information, inter-regional comparisons and for planning regional surveillance strategies.

Effects of betaine supplementation on dry matter intake, milk characteristics, plasma non-esterified fatty acids, and beta-hydroxybutyric acid in dairy cattle: a meta-analysis.

Betaine supplementation in dairy cattle has gained attention due to its potential benefits to production and health as a methyl donor, which can play a crucial role in the metabolism of dairy cows. The objective of the current meta-analysis was to quantify the effects of betaine supplementation on milk production, composition, beta-hydroxybutyric acid (BHBA), and non-esterified fatty acids (NEFA). A systematic literature search was carried out, all relevant studies were retrieved, and the meta-analysis was carried out. The mean difference (MD) for dry matter intake (DMI) using the random-effects model was 0.499 kg/day (P < 0.0001). The subgroup analysis indicated that supplementing betaine in heat-stressed cows increased DMI by 0.584 kg/day (P < 0.001), while in cows not exposed to heat stress, DMI was increased by 0.381 kg/day (P = 0.007). The energy-corrected milk (ECM) increased by 1.36 kg/day (P < 0.0001). The milk fat yield was significantly increased in betaine-supplemented cows (MD = 0.040 kg/day, 95% CI = 0.015 to 0.065). The milk protein yield (kg/day) (MD = 0.014, P = 0.138) was increased (MD = 0.035, P = 0.0005) by betaine supplementation. The lactose yield (kg/day) was also significantly higher (MD = 0.055, P = 0.020) in betaine-supplemented cows. The standardized mean difference (SMD) for NEFA (SMD = -0.447, 95% CI = -1.029 to 0.135, P = 0.114) and BHBA (SMD = -0.130, 95% CI = -0.491 to 0.234). In conclusion, the findings from this meta-analysis suggest that betaine supplementation positively influences DMI, ECM, milk fat yield, milk lactose yield, and milk protein yield. Subgroup analysis further indicated that the positive effects on DMI are greater in heat-stressed cows compared to those not exposed to heat stress. The analysis did not find significant effects on the levels of NEFA or BHBA, suggesting that betaine supplementation may not directly influence these metabolic parameters.

Tick fever agents in Holstein calves grazing in a tropical region: predisposing factors, impact on milk production, productivity, and role of Rhipicephalus microplus in epidemiology.

The present study aimed to evaluate under dairy farm conditions the predisposing factors, impact on milk production and productivity, and the role of Rhipicephalus microplus in the epidemiology of tick fever agents in Holstein calves grazing in a tropical region. A total of 4292 pure female Holsteins were evaluated at a commercial farm. Until April 2020, calves had contact with R. microplus for between 3 and 24 months, while after April 2020, no animal had further contact with ticks. Three times a week the rectal temperature (RT) of all animals was determined, and blood samples were collected for evaluation of tick fever (TF) agents from those that showed RT >39.3 °C. Specific treatment was performed against Anaplasma marginale, Babesia bigemina and Babesia bovis when these TF agents were diagnosed in the blood smears. The number of relapses and treatments for TF agents were sub-classified into scales (1, 2, 3, 4, 5, 6 or 7-10 treatments or relapses, and animals that received blood transfusions). Within each sub-class, the health data of calves during lactation along with productivity data were analyzed. Based in the results, whether an animal received colostrum enriched with powdered colostrum substitute, whether the animal was an embryo transfer calf, and the weight at which each calf was weaned were ascertained as factors leading to more recurrences or treatments against TF agents in post-weaned calves. On average, each recurrence of TF agents that a heifer presented between three and seven months decreased milk production by 213.5 liters in the first lactation. Calves that received a blood transfusion had lower milk production at first lactation; lower weight at first fixed-time artificial insemination (FTAI); older age at first FTAI; older age at first, second, and third calving; and delayed age at third calving by 140 days compared to the farm average. R. microplus was the main agent causing clinical cases of TF on the farm, and 10,770 treatments against TF agents were carried out when calves aged between three and seven months had contact with this tick species (2018 and 2019). When the animals no longer had contact with ticks (2022 and 2023), there were no recurrences or treatments against TF agents despite the presence on the farm of S. calcitrans, which can maintain the transmission of A. marginale to the herd.

Application of cold plasma therapy for managing subclinical mastitis in cows induced by Streptococcus agalactiae, Streptococcus uberis and Escherichia coli.

The primary objective of this study was to assess the effectiveness of cold plasma therapy in managing subclinical mastitis in cows caused by Streptococcus agalactiae, Streptococcus uberis and Escherichia coli. After detection of mastitis pathogens, 38 cows were selected for cold plasma therapy for five days. On the fifth day of treatment, the mastitis agents were re-examined and no causative agents were identified. An additional evaluation conducted 28 days later confirmed the absence of mastitis. Cow productivity, milk composition and quality indicators were assessed at the beginning of the experiment and 32 days from the start (28 days after treatment cessation). After the mastitis treatment, the somatic cell count decreased significantly by between 2.89 and 7.09 times, and the milk yield of the cows at the end of the experiment increased from 0.63 kg per day to 2.82 kg per day (P < 0.01). These results highlight the potential of this innovative approach for managing a prevalent disease that causes substantial losses in the dairy industry. Furthermore, they lay the groundwork for expanded research involving larger sample sizes.