Hasil untuk "Dairy processing. Dairy products"

Thibaut Lurier, Marie-Anne Arcangioli

Sainan Yu, Yuyang Liu, Xueqi Fu et al.

ABSTRACT: Bioactive peptides derived from milk proteins have attracted increasing interest due to their potential as natural sweet-tasting compounds. In this study, an integrated in silico strategy was developed to identify sweet peptides from milk proteins. The approach combined machine learning models capable of predicting both sweet and bitter taste properties to improve the accuracy of peptide selection. Peptides generated from virtual enzymatic hydrolysis were screened using 3 machine learning models. Candidates predicted to be sweet and nonbitter were virtually screened to evaluate their binding affinity to the human sweet taste receptor T1R2/T1R3. Peptides with favorable docking scores were further evaluated for their pharmacokinetic properties using computational prediction tools. Based on the combined results of docking and an absorption, distribution, metabolism, excretion, and toxicity assessment, 5 peptides (MDG, MKG, TSG, CDSS, and DSTT) were selected for further analysis. Molecular docking interaction analysis revealed that hydrogen bonding and π–π stacking were the predominant interaction modes at the binding site. Molecular dynamics simulations confirmed the structural stability of the 5 complexes, with MDG, CDSS, and DSTT showing reduced binding fluctuation and minimal receptor conformational changes, suggesting stronger binding stability. Electronic tongue analysis validated the presence of detectable sweet taste signals for all 5 peptides. Among them, MDG, CDSS, and DSTT demonstrated particularly stable interactions and clear sweetness responses, highlighting their potential as candidates for natural sweetener development. This study presents a practical computational framework for the efficient screening and evaluation of sweet peptides from milk protein sources. The proposed strategy may support the discovery of dairy-derived sweeteners with potential applications in sugar-reduced or functional dairy products.

Gabriel Vasilakis, Antonios Georgoulakis, Eleni Dalaka et al.

Microbial bioconversion of agro-industrial by-products into high-value-added metabolites such as polysaccharides or lipids serves a dual purpose: mitigating environmental pollution through waste reduction and supporting the development of novel bioproducts. In this study, a non-conventional, poorly studied <i>Cryptococcus albidus</i> strain was initially assessed for its ability to grow on semi-defined media containing lactose, glycerol, or glucose under three distinct nitrogen availability conditions at C/N equal to 20, 80, and 160 mol/mol in shake flask cultures. The goal was to evaluate biomass production and synthesis of valuable metabolites under these conditions. <i>C</i>. <i>albidus</i> demonstrated robust growth on all commercial carbon sources, particularly under nitrogen-rich conditions, producing more than 25.0 g/L of microbial biomass with a high intracellular polysaccharide content (>45%, <i>w</i>/<i>w</i>). Additionally, mannitol production was detected in cultures with glycerol and glucose (9.1 and 13.1 g/L, respectively), especially after nitrogen depletion. Subsequently, <i>C</i>. <i>albidus</i> and a <i>Cutaneotrichosporon curvatus</i> strain were batch-cultivated using pretreated secondary cheese whey (SCW) as a carbon-rich waste substrate. When cultivated on SCW, both yeast strains partially metabolized lactose and produced polysaccharide-rich biomass, dominated by β-glucans (>29% of total biomass), compounds known for their functional and bioactive properties. The cellular polysaccharides (cPS extracted from <i>C</i>. <i>albidus</i> exhibited cytotoxic effects against cancer cells, suggesting their potential use as biological response modifiers. In contrast, the cPS from <i>C</i>. <i>curvatus</i> did not affect cell viability, indicating their promise as ingredients for applications in the food, feed, pharmaceutical, or cosmetic sectors.

B.L. Kelly, K.L. Proudfoot, T.E. Da Silva et al.

ABSTRACT: With increased interest in precision livestock farming (PLF) by dairy producers, a clearer understanding of public perceptions is needed to ensure that use of these technologies is socially sustainable. This study sought to (1) characterize public perceptions toward precision dairy technologies (PDT), trust in farmers using PDT, and likelihood to purchase (LTP) dairy produced with PDT; (2) describe how these perceptions may be influenced by information framing about the potential effects of PDT use; and (3) evaluate the influence of demographic characteristics of the participant sample. In an online survey distributed to US residents (n = 2,365), participants randomly received 1 of 8 vignettes, each containing either positively or negatively valenced information about hypothetical PDT effects on human-animal relationship, data transparency, and animal welfare. Perceptions toward PDT were assessed with Likert item questions before and after vignette exposure and through representational thematic text analysis of open-ended responses (n = 80 randomly selected) justifying the Likert responses. Linear models were selected using backward selection to assess significant predictors of baseline and shifts in perceptions toward PDT, farmer trust, and LTP. Baseline perceptions toward PDT, trust, and LTP were generally positive, with more positive perceptions associated with higher incomes, rural backgrounds, and dairy consumers more knowledgeable about production; in contrast, baseline perceptions were more negative among participants with higher levels of concern toward animals. Across the sample, participants experienced slight negative shifts in PDT perceptions after vignette exposure, with those who indicated a voting preference for the Democratic party (e.g., politically liberal) and who had more positive attitudes about animal protection more vulnerable to negative perception shifts. Generally, information about data transparency did not shift perceptions of PDT in either direction. However, the valence of animal welfare information strongly predicted the direction of perception shifts, such that negative information was particularly influential in generating worsened perceptions of PDT, even if participants received positive information about other attributes. Similarly, the perceived effect of PDT on cows was the most frequently raised theme in the qualitative responses, though participants also focused on ethical acceptability of the technology itself and how it might affect farmers. We suggest that for the dairy industry to maintain its social license to operate, it will benefit from more closely engaging with public concerns regarding potential effects of PDT on animal welfare and the relationship between farmers and animals.

Elizabeth R. Russell, Marina A.G. von Keyserlingk, Daniel M. Weary

ABSTRACT: Decades of research have helped inform practices on how to care for calves, but little is known about how well these practices are adopted on commercial dairy farms. The primary aim of this study was to describe rearing practices of dairy calves in British Columbia, Canada. Measures of calf growth are sometimes used to assess success in calf rearing, so a secondary aim was to describe methods used to assess calf growth on these farms. All 437 dairy farms in the province were invited to participate in a survey distributed via email from the British Columbia Ministry of Agriculture and Food from June to December 2023. A total of 63 completed responses were received (i.e., 14.4% of those invited). Milking herd size averaged (± SD) 167 ± 172 cows, and the primary breed was Holstein for 84.1% of respondents. Most (63.5%) farms housed calves individually before weaning; the remainder used either just social housing (groups of 2 or more; 25.4% of farms) or a combination of individual and social housing (11.1% of farms). Maximum milk allowance averaged 9.5 ± 2.7 L/d, with 86.4% of respondents offering >8 L/d. Teat feeding was used on 71.6% of farms, and 13.1% of farms used automated milk feeders. Two participants reported feeding calves via the dam or nurse cows. Weaning age averaged 75.8 ± 16.3 d, with calf age being the primary criterion for weaning. About half (52.4%) of farms reported monitoring calf growth, and 31.7% of farms reported having a target growth rate. Our results suggest that rearing practices are changing, in that calves are now often fed higher milk rations via a teat, and many farms use social housing. However, individual housing remains prevalent, suggesting research is needed to understand the barriers to adopting social housing on farms. Our findings also suggest the opportunity to improve methods for monitoring calf growth; improved measures may facilitate evidence-based evaluations of calf rearing and weaning protocols on farms.

Bichen Zhao, Ming Li, Huijing Zhang et al.

ABSTRACT: Subclinical ketosis (SCK) is highly prevalent and easily overlooked, with insidious and slow progression of hepatic injury, often characterized by an imbalance in immune homeostasis. In nonruminants, macrophage polarization plays an important regulatory role in hepatic lipid accumulation, fibrosis, and inflammatory processes. Thus, we aimed to investigate the status of hepatic macrophage polarization in SCK cows and to corroborate its association with liver injury and inflammation. Twelve Holstein dairy cows (parity 2–4) were selected, and liver biopsy and blood were collected on the second week postpartum (10–14 d DIM). On the basis of serum beta-hydroxybutyric acid (BHBA) concentrations, selected cows were categorized into healthy (n = 6; BHBA <1.0 mM) and SCK (n = 6; 1.2 mM ≤ BHBA < 3.0 mM) groups. Serum biochemical parameters were measured using an automatic biochemical analyzer, which indicated higher serum levels of BHBA and nonesterified fatty acids and an upregulation of liver injury indicators (aspartate aminotransferase [AST], alanine aminotransferase [ALT], total protein, globulin) in SCK cows compared with healthy cows. The ELISA assays revealed that SCK cows displayed systemic low-grade inflammation, as demonstrated by increased serum levels of haptoglobin, serum amyloid A, TGF-β, IFN-γ, and IL-1β. Liver biopsies revealed pathological histological alterations, hepatic inflammation, and macrophage polarization status. Oil Red staining indicated steatosis, whereas Sirius red staining demonstrated mild extracellular matrix deposition in the liver of SCK cows. The expression of inflammatory response-related proteins (TLR4, p-NFκB, p-I-κB, NLRP3, and Caspase 1) was elevated in the liver of SCK cows, with the increased mean fluorescence intensity of NFκB further confirming the activation of the inflammatory pathway. Furthermore, the levels of pro-inflammatory factors, TNF-α and IFN-γ, were elevated in the tissue homogenate. Macrophage phenotypic changes in SCK cows were further explored based on the results of liver injury and inflammation. Compared with healthy cows, the protein and mRNA abundance of the macrophage marker CD68 in the liver of SCK cows was higher, along with an increased mean fluorescence intensity of CD68. The SCK cows also exhibited reduced mRNA expression of the Kupffer cell marker CLEC4F and elevated chemokine levels (CXCL1 and CCL2). As evidenced by greater protein and mRNA abundance of macrophage M1 polarization markers (iNOS, IL-1β, CD86, IL-6, IL-12b, and CCL3), higher fluorescence intensity of iNOS and CD86, and an increased number of CD68+/CD86+-positive cells observed via immunofluorescence, the macrophage polarization phenotype in the liver of SCK cows was predominantly M1. In contrast, the protein and mRNA abundances of M2 polarization markers (CD206, IL-10, and Arg1) were lower in SCK cows, accompanied by a reduced fluorescence intensity of CD206 and a lower number of CD68+/CD206+-positive cells. Overall, the present study revealed that the number of macrophages in liver is enhanced during subclinical ketosis and is dominated by pro-inflammatory macrophages (M1 macrophages). This could partly explain the increased risk of steatosis, fibrosis, and inflammatory response processes in these cows.

R. Martineau, D.R. Ouellet, D. Pellerin et al.

ABSTRACT: Accurate prediction of intestinal digestible flows of EAA (DigFlowEAA) is a crucial step for adequately balancing EAA supply to reduce the amount of CP fed to dairy cows, without compromising either milk production or the health status of the animals. The objective of this meta-analysis was to compare the performance of 3 dairy feed evaluation systems (FES) to predict DigFlowEAA (NRC; National Academies of Sciences, Engineering and Medicine [NASEM]; and Cornell Net Carbohydrate and Protein System version 6.5.5 [CNCPS]) in relation to observed net portal appearance (NPAobs) of EAA. Although the DigFlowEAA cannot be measured directly and none of the FES were designed to estimate the net portal appearance (NPA) of EAA, NPA could be predicted (NPApred) from estimations of DigFlowEAA minus the estimated metabolic fecal protein (MFP). This NPApred, however, would not include any oxidation for EAA or synthesis for Arg, a semi-EAA, occurring during the absorption process. Intuitively, the prediction errors should be smallest for the DigFlowEAA best predicted across the 3 FES and for the EAA not oxidized by the portal-drained viscera (PDV). The dataset included 83 NPAobs treatment means from 25 studies. To avoid type I error, mean and linear biases were considered biologically relevant if statistically significant and representing >5.0% of the observed mean (%obs.mean). The NPApred of branched-chain AA (BCAA) and Thr showed a similar pattern across the 3 FES, with all overpredicted relative to NPAobs (6%obs.mean to 27%obs.mean). The NPApred for the other EAA were more variable: (1) underprediction of Arg (9%obs.mean to 20%obs.mean) with NRC and NASEM, and Met (8%obs.mean) with NRC, (2) overprediction of Lys and Phe (5%obs.mean to 11%obs.mean) with NASEM, and His, Met and Trp (8%obs.mean to 14%obs.mean) with CNCPS, and (3) linear biases for Arg (7%obs.mean) with NASEM, and for His, Lys, Met, and Phe (5%obs.mean to 14%obs.mean) with CNCPS. In our previously reported meta-analysis, the mean and linear biases between observed and predicted EAA postruminal outflow were related to the site of digesta sampling (duodenal vs. omasal) for some EAA, but it was not possible to determine which sampling site was representative of the true supply of EAA to the cows. In an effort to solve this issue, predictions of NPA (except Trp) were recalculated removing the mean and linear biases observed in duodenal and omasal studies of our previous meta-analysis (NPArec_duo and NPArec_oma). Compared with NPApred, the pattern of BCAA and Thr remained overpredicted in NPArec_duo and NPArec_oma across the 3 FES. This strongly suggests oxidation of Ile, Leu, Val, and Thr by the PDV averaging, respectively, 12% (range 6% to 18%), 16% (range 14% to 17%), 24% (range 18% to 27%), and 19% (range 13% to 23%) of NPAobs across the 3 FES. The magnitude of PDV oxidation, however, would be related to the ratio of DigFlowEAA to digestible energy intake. The negative mean biases for Arg NPApred would suggest synthesis by the PDV. For the BCAA, Thr, and Arg, because of the uncertainty on the biological quantification of the differences between NPAobs and NPApred, the relative performance of each FES could not be assessed. Assuming no oxidation of the other EAA (i.e., His, Lys, Met, and Phe) by the PDV and an adequate estimation of MFP, their NPAobs indicate that the DigFlow of (1) Met is underpredicted by NRC, (2) Lys is overpredicted by NASEM, (3) His and Met are overpredicted with CNCPS, and (4) His, Lys, Met, and Phe present a linear bias with CNCPS, supporting similar observations on the postruminal EAA outflows from our previous meta-analysis. Based on current NPAobs studies and our previous meta-analysis on postruminal outflows of EAA, sampling digesta at the duodenum appears to be more representative of the true supply of EAA to the cows than sampling at the omasum.

L. de Souza Ferreira, S. Bolin, A. Abuelo et al.

Hemotropic mycoplasmas are unculturable bacteria that infect the surface of red blood cells of several mammalian species including cattle. The importance of hemoplasmas in cattle remains unclear and limited information is available about biological routes of transmission. The objective of this cross-sectional study was to determine the prevalence of transplacental transmission of hemoplasmas and to determine if colostrum of infected cows contained DNA from hemoplasma organisms. In March 2023, researchers collected colostrum and peripheral blood samples from 39 dairy cows and their newborn calves (before ingestion of colostrum) at a single dairy farm in Michigan. Detection of Mycoplasma wenyonii and Candidatus Mycoplasma haemobos was performed using real-time PCR. The apparent prevalence of hemoplasma infection in dams was 100%, with 84.6% (33/39) co-infected with both M. wenyonii and C. M. haemobos, whereas the remaining 15.3% (6/39) were infected solely with C. M. haemobos. The prevalence of newborn calves infected with C. M. haemobos was 10.2% (4/39), and none were infected with M. wenyonii. No colostrum samples tested positive for either M. wenyonii or C. M. haemobos. This is the first report of vertical transmission of hemoplasmas in a dairy herd located in the United States. However, the relatively low prevalence of infected newborn calves suggests that transplacental transmission is not the predominant pathway of infection. The absence of positive tests in colostrum may indicate ingestion of colostrum contaminated with hemoplasmas is not common. The clinical importance of fetal infection remains known.

Guillermo Martinez-Boggio, Hugo F. Monteiro, Fabio S. Lima et al.

ABSTRACT: The rumen microbiome is crucial for converting feed into absorbable nutrients used for milk synthesis, and the efficiency of this process directly affects the profitability and sustainability of the dairy industry. Recent studies have found that the rumen microbial composition explains part of the variation in feed efficiency traits, including dry matter intake, milk energy, and residual feed intake. The main goal of this study was to reveal relationships between the host genome, the rumen microbiome, and dairy cow feed efficiency using structural equation models. Our specific objectives were to (1) infer the mediation effects of the rumen microbiome on feed efficiency traits, (2) estimate the direct and total heritability of feed efficiency traits, and (3) calculate the direct and total breeding values of feed efficiency traits. Data consisted of dry matter intake, milk energy, and residual feed intake records, SNP genotype data, and 16S rRNA rumen microbial abundances from 448 mid-lactation Holstein cows from 2 research farms. We implemented structural equation models such that the host genome directly affects the phenotype (GP → P) and the rumen microbiome (GM → P), and the microbiome affects the phenotype (M → P), partially mediating the effect of the host genome on the phenotype (G → M → P). We found that 7% to 30% of microbes within the rumen microbial community had structural coefficients different from zero. We classified these microbes into 3 groups that could have different uses in dairy farming. Microbes with heritability <0.10 but significant causal effects on feed efficiency are attractive for external interventions. On the other hand, 2 groups of microbes with heritability ≥0.10, significant causal effects, and genetic covariances and causal effects with the same or opposite sign to feed efficiency are attractive for selective breeding, improving or decreasing the trait heritability and response to selection, respectively. In general, the inclusion of the different microbes in genomic models tends to decrease the trait heritability rather than increase it, ranging from −15% to +5% depending on the microbial group and phenotypic trait. Our findings provide more understanding to target rumen microbes that can be manipulated, either through selection or management interventions, in order to improve feed efficiency traits.

L. Pisoni, S. Marti, J. Pujols et al.

ABSTRACT: Colostrum consumption is crucial for passive immunization and development of the newborn calf. However, the incidence on failed transfer of passive immunity in male calves destined to dairy-beef production remains high to date. In addition, the lack of an automated procedure to validate the immunization status upon arrival at rearing facilities in calves beyond 14 d of age impedes the identification of failed transfer of passive immunity, and therefore, of those calves at high risk of suffering diseases. For this study, 82 newborn male Holstein calves (43.3 ± 0.86 kg of body weight; mean ± standard error) from a commercial dairy farm were used to investigate potential serum biomarkers of colostrum provision. The potential biomarkers selected were IgG, IgG1, cholesterol, alkaline phosphatase, gamma-glutamyl transferase (GGT), and total protein (TP). Treatments were as follows: high-colostrum (HC; n = 49), in which calves received 4 L of colostrum within the first 2 h after birth and 2 L of colostrum in the next 3 feedings within the first 24 h after birth, for a total of 10 L of colostrum; and low-colostrum (LC; n = 33), in which calves received only 2 L of colostrum within the first 2 h after birth. After colostrum consumption, calves were allocated to individual hutches and fed 2 L of milk replacer twice daily at a concentration of 125 g/L as fed. Starter feed and water were offered ad libitum. At approximately 14 d of age (14.2 ± 0.81 d of age; mean ± standard error) calves were transported 2.5 h to a research unit at IRTA (Torre Marimon, Spain) simulating the arrival to a rearing facility. Blood samples were collected before feeding at birth, 48 h after birth, and at arrival to the rearing facility. Results on the serum concentrations of the potential biomarkers at arrival to the rearing facility showed that IgG, IgG1, GGT, and TP were greater for the HC calves compared with the LC calves. Serum concentrations of cholesterol and alkaline phosphatase did not show differences between treatment groups. Additionally, body weight losses from birth until arrival to the rearing facility were greater for the LC treatment compared with the HC. Because of their low cost, quickness, and ease of measurement, GGT and TP were good indicators of colostrum intake in calves arriving at rearing facilities beyond 14 d of age.

Christin Schmidtmann, Dierck Segelke, Jörn Bennewitz et al.

ABSTRACT: This study sheds light on the genetic complexity and interplay of production, body size, and metabolic health in dairy cattle. Phenotypes for body size-related traits from conformation classification (130,166 animals) and production (101,562 animals) of primiparous German Holstein cows were available. Additionally, 21,992, 16,641, and 7,096 animals were from herds with recordings of the metabolic diseases ketosis, displaced abomasum, and milk fever in first, second, and third lactation. Moreover, all animals were genotyped. Heritabilities of traits and genetic correlations between all traits were estimated and GWAS were performed. Heritability was between 0.240 and 0.333 for production and between 0.149 and 0.368 for body size traits. Metabolic diseases were lowly heritable, with estimates ranging from 0.011 to 0.029 in primiparous cows, from 0.008 to 0.031 in second lactation, and from 0.037 to 0.052 in third lactation. Production was found to have negative genetic correlations with body condition score (BCS; −0.279 to −0.343) and udder depth (−0.348 to −0.419). Positive correlations were observed for production and body depth (0.138–0.228), dairy character (DCH) (0.334–0.422), and stature (STAT) (0.084–0.158). In first parity cows, metabolic disease traits were unfavorably correlated with production, with genetic correlations varying from 0.111 to 0.224, implying that higher yielding cows have more metabolic problems. Genetic correlations of disease traits in second and third lactation with production in primiparous cows were low to moderate and in most cases unfavorable. While BCS was negatively correlated with metabolic diseases (−0.255 to −0.470), positive correlations were found between disease traits and DCH (0.269–0.469) as well as STAT (0.172–0.242). Thus, the results indicate that larger and sharper animals with low BCS are more susceptible to metabolic disorders. Genome-wide association studies revealed several significantly associated SNPs for production and conformation traits, confirming previous findings from literature. Moreover, for production and conformation traits, shared significant signals on Bos taurus autosome (BTA) 5 (88.36 Mb) and BTA 6 (86.40 to 87.27 Mb) were found, implying pleiotropy. Additionally, significant SNPs were observed for metabolic diseases on BTA 3, 10, 14, 17, and 26 in first lactation and on BTA 2, 6, 8, 17, and 23 in third lactation. Overall, this study provides important insights into the genetic basis and interrelations of relevant traits in today's Holstein cattle breeding programs, and findings may help to improve selection decisions.

P.M. Peixoto, J.J. Bromfield, E.S. Ribeiro et al.

ABSTRACT: The objective was to characterize endometrial transcriptome on d 17 of gestation in dairy cows according to conceptus length. Nonlactating Holstein cows (n = 48) were slaughtered 17 d after AI and the uterine horn ipsilateral to the corpus luteum (CL) was flushed with saline solution. Recovered conceptuses were classified as small (1.2–6.9 cm; n = 9), medium (10.5–16.0 cm; n = 9), or large (18.0–26.4 cm; n = 10). Samples of intercaruncular endometrium dissected from the caudal, intermediate, and cranial portions of the uterine horn ipsilateral to the pregnancy were pooled for analyses. Total mRNA was extracted from endometrial tissue and subjected to transcriptome analyses using the Affymetrix Gene Chip Bovine array. Data were normalized using the GCRMA method and analyzed by robust regression using the Linear Models for Microarray library within Bioconductor in R. Transcripts with P ≤ 0.05 after adjustment for false discovery rate and fold change ≥1.5 were considered differentially expressed. Functional analyses were conducted using the Ingenuity Pathway Analysis platform. Comparisons between endometria of cows carrying large versus small (LvsS), large versus medium (LvsM), and medium versus small (MvsS) conceptuses yielded a total of 235, 21, and 94 differentially expressed transcripts, respectively. Top canonical pathways included the antigen presentation pathway and Th1/Th2 activation pathways, both for LvsS and MvsS. Interferon-α and -γ were identified as activated upstream regulators, primarily based on differently expressed transcripts such as IDO1, ISG20, WARS, LGALS9, IFI44, and PSMB9 (LvsS and MvsS). For LvsS, regulator analyses revealed predicted activation of FOXO1, IFN, NFACTC2, IL-12, IL-6, and IL-18, whereas it depicted inhibition of IL10RA and ZBTB1. Changes in these regulators were associated with a downstream activation of leukocytes, as well as quantity and expansion of T lymphocytes. Canonical pathways associated with the comparison LvsM included cell cycle G2/M DNA damage checkpoint regulation, cell cycle control of chromosomal replication. Moreover, tretinoin was predicted, as activated in upstream analysis for the same comparison. In conclusion, most of the differently expressed transcripts in the endometrium on d 17 of gestation were identified between cows carrying small conceptuses compared with counterparts carrying medium and large conceptuses and were involved with pathways associated with modulation of the immune response.

M.M. Perez, E.M. Cabrera, J.O. Giordano

ABSTRACT: Our objectives were to compare the proportion of lactating dairy cows diagnosed with health disorders (HD) and herd performance when using a health monitoring program designed to rely primarily but not exclusively on alerts from automated health monitoring (AHM) systems or a health monitoring program based primarily on systematic clinical examinations, milk yield monitoring, and visual observation of cows. In a clinical trial, at ∼30 d before expected parturition, nulliparous and parous Holstein cows, stratified by parity and days in gestation, were randomly assigned to the high-intensity clinical monitoring (HIC-M; n = 625) or automated monitoring (AUT-M; n = 624) treatment. Cows were fitted with a neck-attached rumination and physical activity monitoring tag, and individual daily milk yield data were collected from parlor milk meters. For cows in HIC-M, clinical examination was conducted daily until 10 d in milk (DIM) and then in response to milk yield reduction alerts or visual observation of clinical signs of HD over the course of 21 DIM. For cows in AUT-M, clinical examination until 21 DIM was because of health index (HI) score alerts and reduced milk yield alerts. The HI score alerts used were generated based on the manufacturer's settings for the system for the last 2-h period before cows were selected for examination. Visual observation of clinical signs of HD was used for identifying cows potentially missed by automated alerts. Binomial and quantitative data were analyzed by logistic regression and ANOVA with repeated measures, respectively. The percentage of cows diagnosed with at least 1 HD during the experimental treatments risk period tended to be greater and the incidence rate ratio of HD diagnosed was greater in the HIC-M than in the AUT-M treatment. We found no difference between treatments for cows that exited the herd up to 60 or 150 DIM, but more cows tended to exit the herd from 61 to 150 DIM in the HIC-M than in the AUT-M treatment. No differences were detectable between treatments in daily or total milk yield to 21 DIM or in weekly mean milk yield and total milk yield to 150 DIM. More cows were inseminated in estrus for first service if in the HIC-M treatment and had no HD diagnosed than if in the HIC-M treatment but with HD diagnosed, or in the AUT-M treatment and had no HD diagnosed. Cows in the AUT-M treatment with HD diagnosed did not differ from other groups. No differences between treatments were observed in pregnancies per artificial insemination or pregnancy loss for first service. Despite a reduction in the risk of diagnosis of HD, no evidence indicated that a health monitoring program that relied on AHM system alerts to select cows for clinical examination reduced herd performance compared with a more intensive program that included systematic clinical examinations of all cows for the first 10 DIM, reduced milk yield alerts, and visual observation. However, to obtain the same herd performance as with the HIC-M treatment, the AUT-M treatment required use of visual observation. In conclusion, a health monitoring program designed to rely primarily on targeted clinical examination based on alerts from automated health monitoring systems might be a feasible alternative to programs that rely more on clinical examination, provided that visual observation is used to identify cows not detected by automated alerts.

Xinyu Wang, Yongxin Hu, Hongkai Tan et al.

ABSTRACT: Cow milk is an important source of food protein for children; however, it could lead to allergy, especially for infants. α-Lactalbumin (α-LA) and β-lactoglobulin (β-LG) from whey protein make up a relatively high proportion of milk proteins and have received widespread attention as major allergens in milk. However, few studies have identified the epitopes of both proteins simultaneously. In this study, ImmunoCAP and indirect ELISA were first used for detection of sIgE to screen sera from allergic patients with high binding capacity for α-LA and β-LG. Subsequently, the mimotopes was biopanned by phage display technology and bioinformatics and 17 mimic peptide sequences were obtained. Aligned with the sequences of α-LA or β-LG, we identified one linear epitope on α-LA at AA 11–26 and 5 linear epitopes on β-LG at AA 9–29, AA 45–57, AA 77–80, AA 98–101, and AA 121–135, respectively. Meanwhile, the 8 conformational epitopes and their distributions of α-LA and β-LG were located using the Pepitope Server. Finally, glutamine and lysine were determined as common AA residues for the conformational epitopes both on α-LA and β-LG. Moreover, we found the addition of mouse anti-human IgE during the biopanning process did not significantly affect the identification of the epitopes.

M. Ansari, S. Kargar, M.A. Eslami et al.

ABSTRACT: This study was performed to determine the early-life (first month of age) supplementation of liquid feed with fennel seed powder (FSP) or oregano leaf powder (OLP) on growth performance, health, and blood biochemical attributes in preweaning dairy calves. Holstein female calves (n = 57; 1 d of age; 34.1 ± 0.97 kg of BW; mean ± SE) were assigned randomly to receive liquid feed (colostrum and milk) with no added herbal plants (CON) or supplemented with FSP (3 g/d) or OLP (30 g/d) during the first month of age. The calves received pooled colostrum (4.5 kg/d on the first 2 d of life; total solids = 25.0% ± 1.24; mean ± SD) and then pooled waste milk (6 kg/d from d 3 to 44, 5 kg/d from d 45 to 46, 4 kg/d from d 47 to 48, and 3 kg/d from d 49 to 50 of the trial; total solids = 12.54% ± 0.50) to ensure they receive same mixed liquid feed daily. The calves had unlimited access to the starter feed and fresh water and remained in the study until weaning on d 51 of age. The average mean temperature-humidity index was 70.1 units (ranging between 61.9 to 78.2) during the experiment, indicating a borderline degree of environmental heat-load. The amount of starter feed offered and refused was recorded daily. The calves were weighed immediately after birth and every 10 d thereafter, before the morning feeding. Jugular blood samples were taken immediately before and 24 h after colostrum feeding, at first month of age, and at weaning to quantify serum concentrations of glucose, urea N, cholesterol, triglycerides, total proteins, albumin, globulin, aspartate transferase, alanine transferase, total antioxidant status, and malondialdehyde. Health checks including rectal temperature, general appearance (on a 1–5 score system), fecal score (on a 1–5 score system), and bovine respiratory disease (BRD; scored using the University of Wisconsin Calf Health Chart) were performed daily, by a veterinarian who was unaware of the calf treatment allocations, for all calves over the study period. A repeated-measures ANOVA was used to compare growth performance and blood metabolites among treatment groups, and a logistic regression model using a binomial distribution (PROC GLIMMIX, SAS v. 9.4, SAS Institute Inc.) was used to assess the chance of elevated rectal temperature (≥39.4°C), general appearance (≥2), diarrhea (≥3), and BRD. A Poisson regression model (PROC GENMOD) was also used to test group differences in the experience of days with elevated rectal temperature and general appearance, and frequency and duration of diarrhea or BRD. Total nutrient intake (DM, CP, and ME, but not ether extract) originating from milk and starter feed was greater in OLP- (but not FSP-) supplemented calves compared with CON group, being partially associated with difference in milk refusal. Calves receiving FSP and OLP had greater average daily gain, BW gain, skeletal gain (withers height or heart girth, respectively), and feed efficiency compared with CON animals with no difference between FSP and OLP. Rectal temperature was lower in FSP- (but not OLP-) supplemented calves compared with CON animals. The CON animals had a greater chance of experiencing higher rectal temperature (≥39.4°C; odds ratio = 1.55 and confidence interval = 1.12–2.15 and odds ratio = 1.33 and confidence interval = 0.92–1.90, respectively, compared with FSP and OLP) and general appearance (≥2; odds ratio = 1.99 and confidence interval = 1.45–2.74 and odds ratio = 1.45 and confidence interval = 1.03–2.05), and diarrhea (odds ratio = 1.47 and confidence interval = 1.11–1.97 and odds ratio = 1.49 and confidence interval = 1.07–2.08) compared with those receiving FSP or OLP; with the chance of BRD being lower in FSP- (but not OLP-) supplemented versus CON animals (odds ratio = 1.59 and confidence interval = 1.13–2.23). As compared with OLP and CON groups, FSP treatment resulted in shorter days with elevated rectal temperature and general appearance. Supplementing FSP or OLP decreased the duration of diarrhea and BRD but not their frequency compared with CON. Duration of diarrhea was not different between FSP- or OLP-supplemented calves but calves supplemented with FSP had shorter days with BRD compared with OLP-supplemented calves. Of the blood constituents measured on d 30, concentration of aspartate transferase was higher in FSP- (but not CON) versus OLP-supplemented calves, indicating a transient liver tissue damage or dysfunction which was subsequently ameliorated. At weaning, blood concentration of triglycerides was higher in FSP and OLP groups compared with CON group. Supplementation of the liquid feed with FSP or OLP, especially FSP, had beneficial effects on calf growth performance and health. Further experiments are warranted for optimizing the dosage and duration of feeding FSP or OLP as feed additives for dairy calves.

Ahmed R.A. Hammam, Steven L. Beckman, Lloyd E. Metzger

ABSTRACT: Concentrated micellar casein (CMC) is a high-protein ingredient that can be used in process cheese product formulations. The objectives of this study were to develop a process to produce CMC and to evaluate the effect of sodium chloride and sodium citrate on its storage stability. Skim milk was pasteurized at 76°C for 16 s and cooled to ≤4°C. The skim milk was heated to 50°C using a plate heat exchanger and microfiltered with a graded permeability (GP) ceramic microfiltration (MF) membrane system (0.1 μm) in a continuous feed-and-bleed mode (flux of 71.43 L/m2 per hour) using a 3× concentration factor (CF) to produce a 3× MF retentate. Subsequently, the retentate of the first stage was diluted 2× with soft water (2 kg of water: 1 kg of retentate) and again MF at 50°C using a 3× CF. The retentate of the second stage was then cooled to 4°C and stored overnight. The following day, the retentate was heated to 63°C and MF in a recirculation mode until the total solids (TS) reached approximately 22% (wt/wt). Subsequently, the MF system temperature was increased to 74°C and MF until the permeate flux was <3 L/m2 per hour. The CMC was then divided into 3 aliquots (approximately 10 kg each) at 74°C. The first portion was a control, whereas 1% of sodium chloride was added to the second portion (T1), and 1% of sodium chloride plus 1% of sodium citrate were added to the third portion (T2). The CMC retentates were transferred hot to sterilized vials and stored at 4°C. This trial was repeated 3 times using separate lots of skim milk. The CMC at d 0 (immediately after manufacturing) contained 25.41% TS, 21.65% true protein (TP), 0.09% nonprotein nitrogen (NPN), and 0.55% noncasein nitrogen (NCN). Mean total aerobic bacterial counts (TBC) in control, T1, and T2 at d 0 were 2.6, 2.5, and 2.8 log cfu/mL, respectively. The level of proteolysis (NCN and NPN values) increased with increasing TBC during 60 d of storage at 4°C. This study determined that CMC with >25% TS and >95% casein as percentage of TP can be manufactured using GP MF ceramic membranes and could be stored up to 60 d at 4°C. The effects of the small increase in NCN and NPN, as well as the addition of sodium chloride or sodium citrate in CMC during 60 d of storage on process cheese characteristics, will be evaluated in subsequent studies.

Raquel Muelas, Gema Romero, José Ramón Díaz et al.

Large amount of vegetal by-products are generated during production and processing steps. Introducing silage from vegetable by-products into dairy goat feed would be of great interest from the point of view of reducing costs and supporting the circular economy. The aim of this research was to study the effect of 40% inclusion of silage broccoli by-products and artichoke plant by-products in the diet of Murciano-Granadina goats throughout the lactation to establish milk suitability for fermented milks production. The novelty of this study is the use of milk from goats fed for a long term with a high inclusion of silages from artichoke plant and broccoli by-products, being the first one on broccoli inclusion. Two starter cultures thermophilic (YO-MIX^TM300), and, mesophilic (MA400) were used and fermented milks were analyzed at two storage times after fermentation. Fermentation enhances antioxidant properties of fermented milks from all diets (<i>p</i> < 0.05), especially when mesophilic starter cultures are used. The main findings are that long term inclusion of 40% silage from broccoli and artichoke plant by-products in balanced diets of dairy goats yields milk suitable for fermentation by yogurt and cheese cultures, the inclusion of broccoli silage enhances antioxidant properties (<i>p</i> < 0.05), and, the inclusion of plant artichoke enhances fatty acids health indexes (<i>p</i> < 0.05).

Anja Sipka, Sabine Mann, Susanna Babasyan et al.

The quantification of cytokines can improve our understanding of immune response and inflammation dynamics in dairy cows. Bead-based assays provide a sensitive, high-throughput platform, allowing for simultaneous quantification of multiple cytokines within a wide linear detection range. Our objective was to develop a multiplex bead-based assay using monoclonal antibodies for simultaneous quantification of bovine tumor necrosis factor (TNF)-α, IL-10, and IFN-γ in plasma and peripheral blood mononuclear cell (PBMC) culture supernatants. Recombinant cytokine standards produced in mammalian cells were used to determine the lower limit of detection and the linear detection range for each cytokine. The lower limit of detection was 110 pg/mL for IL-10, 95 pg/mL for TNF-α, and 20 pg/mL for IFN-γ. The linear quantification range was 110 to 241,000 pg/mL for IL-10, 95 to 620,000 pg/mL for TNF-α, and 20 to 130,000 pg/mL for IFN-γ. All 3 monoclonal capture and detection antibodies were specific for their respective cytokine analyte when using the recombinant IL-10, TNF-α, and IFN-γ standards. Intraassay and interassay coefficients of variation (CV) were <10% and <12%, respectively, for all analytes and samples matrices. Next, concentrations of native cytokines were determined in PBMC culture supernatants (n = 4) and in plasma from whole-blood samples (n = 6) with or without stimulation with Escherichia coli lipopolysaccharide or a mix of phorbol myristate acetate (PMA) and ionomycin. Peak concentrations of all 3 cytokines were secreted from PBMC after PMA/ionomycin stimulation (TNF-α, 8 h, range: 39,266–506,422 pg/mL; IL-10, 18 h, range: 15,770–63,415 pg/mL; IFN-γ 18 h, range: 189,977–492,659 pg/mL). In contrast, the highest concentrations in plasma from whole-blood stimulation were observed for IL-10 and TNF-α after LPS stimulation (TNF-α, 4 h, range: 1,764–13,460 pg/mL; IL-10, 24 h, range: 2,401–6,371 pg/mL), whereas PMA and ionomycin induced the highest secretion of IFN-γ (18 h, range: 53–20,215 pg/mL). In conclusion, the multiplex assay can quantify native IL-10, TNF-α, and IFN-γ across a broad concentration range in bovine plasma and cell culture supernatant, thereby providing a novel tool to evaluate inflammatory profiles in cattle and especially in dairy cows with inflammatory conditions. The existing multiplex assay can be expanded in the future by adding bead assays for additional bovine cytokines.

S.C. Luzzi, R.D. Gardner, B.J. Heins

The objective of this study was to evaluate the taste preference of calves fed Chlorella sp. microalgae produced from dairy lagoon wastewater. Six Holstein dairy heifer calves that were 12 to 14 wk of age (107 ± 3.8 kg of body weight) were fed 0 (control), 30, or 60 g of Chlorella sp. daily, and all calves were fed all treatments in a sequential elimination study. For the 7-d experiment, d 1 to 2 were for diet adaptation and d 3 to 4 were for data collection. During the final 3 d, the primary consumed treatment was removed to determine the second preferred treatment. Calves were ranked for total intake from the consumption of all treatments. The microalgae product used in this study was isolated from dairy wastewater lagoon, and microalgae biomass was produced using outdoor hanging bag bioreactors with Chlorella sp. to recycle the wastewater. The biomass was sterilized and kept frozen at −4°C until fed to calves. Calves were housed individually in hutches with outdoor access under solar panels, with free-choice water. Calves consumed more dry matter from control calf starter (3.4 kg/d) than from the starter with 30 g (2.42 kg/d) or 60 g (1.56 kg/d) of microalgae during the first 2-d period. During the second 2-d period (d 3 and 4), dry matter intake was reduced for the 60 g/d microalgae starter compared with the control and 30 g/d microalgae starters. Five of 6 calves in this study always ranked the control treatment first when given a choice and ranked the 30 g of microalgae starter second choice. Results indicated that microalgae may be added to calf starter; however, calves preferred calf starter without microalgae.

Sukhikh S., Lukin A., Golubtsova Y.

The existing methods of disinfection of containers for fermented milk products proved to be ineffective. The present research featured an antimicrobial preparation based on silver, copper, and zinc nanoparticles as a disinfectant solution. The authors studied the properties of the antimicrobial in order to prove its effectiveness in processing containers to increase the shelf-life of fermented milk products. The size of the silver nanoparticles ranged from 1 to 10 nm. The nanoscale particles of copper were obtained by the method of electric explosion. It was established that the mass fraction of the active substance (active metals) in the antimicrobial was 50.1%; the mass fraction of water was 11.2%; the mass fraction of hydrogen peroxide was 1.0%. To assess the ability of the antimicrobial to increase shelf-life of fermented milk products, the authors analyzed the microbiological properties of cottage cheese. The 50-gram samples were packed in pre-treated polyethylene containers that had been cleaned with the antimicrobial. After that the samples were left for storage at minus 4 ± 1°C. The quality and the microbiological state of the cottage cheese was evaluated on days 3, 5, 7, 9, 11, and 13, which was justified by the experimental conditions and regulatory documentation. Eventually, it was established that the product contained no pathogenic bacteria, such as L. monocytogenes, Salmonella, E. coli, staphylococci, yeast, molds or any viable microbial cells. It was proved that the test sample retained its consumer properties for 13 days, while the control sample was found unusable by day 7. Thus, by using the antimicrobial, it was possible to increase the shelf life of the dairy product by more than 5 days.