Residual feed intake is related to metabolic and inflammatory response during the preweaning period in Italian Simmental calves.

Residual Feed Intake (RFI) is defined as the difference between measured and predicted intake. Understanding its biological regulators could benefit farm profit margins. The most-efficient animals (M-Eff) have observed intake smaller than predicted resulting in negative RFI, whereas the least-efficient (L-Eff) animals have positive RFI. Hence, this observational study aimed at retrospectively comparing the blood immunometabolic profile in calves with divergent RFI during the preweaning period. Twenty-two Italian Simmental calves were monitored from birth through 60 d of age. Calves received 3 L of colostrum from their respective dams. From 2 to 53 d of age, calves were fed a milk replacer twice daily, whereas from 54 to 60 d (i.e., weaning) calves were stepped down to only one meal in the morning. Calves had ad libitum access to concentrate and intakes were recorded daily. The measurement of BW and blood samples were performed at 0, 1, 7, 14, 21, 28, 35, 45, 54, and 60 d of age. Calves were ranked and categorized as M-Eff or L-Eff according to the median RFI value. Median RFI was -0.06 and 0.04 kg of DMI/d for M-Eff and L-Eff, respectively. No evidence for group differences was noted for colostrum and plasma IgG concentrations. Although growth rate was not different, as expected, (0.67 kg/d [95% CI = 0.57-0.76] for both L-Eff and M-Eff) throughout the entire preweaning period (0-60 d), starter intake was greater in L-Eff compared with M-Eff calves (+36%). Overall, M-Eff calves had a greater gain-to-feed ratio compared with L-Eff calves (+16%). Plasma ceruloplasmin, myeloperoxidase, and reactive oxygen metabolites concentrations were greater in L-Eff compared with M-Eff calves. Compared with L-Eff, M-Eff calves had an overall greater plasma concentration of globulin, and γ-glutamyl transferase (indicating a better colostrum uptake) and Zn at 1 d. Retinol and urea were overall greater in L-Eff. The improved efficiency in nutrient utilization observed in M-Eff was paired with a lower grade of oxidative stress and systemic inflammation. L-Eff may have had greater energy expenditure to support the activation of the immune system.

Drying-off dairy cows without antibiotic therapy and orally supplemented with lyophilized Aloe arborescens: effects on rumen activity, immunometabolic profile, and milk yield.

The drying-off is a stressful stage of the lactation cycle of dairy cows that deeply affects cows' metabolism, inflammatory status, and immune system. The promising effects observed during the transition period resulting from supplementation with Aloe arborescens Mill. suggest its potential utility during this phase. A group of 23 Holstein dairy cows with somatic cell count (SCC) less than 200 × 103 cells/ml and without intramammary infections were enroled in the study. Cows were divided into two groups: one orally receiving 10 g/day of A. arborescens Mill. lyophilized powder (AL; 11 cows) between -7 and 7 days from dry-off (DFD), and a control group (CTR; 12 cows). From -14 to 7 DFD and 7 and 28 days from calving, the body condition score and rectal temperature were determined, and rumen fluid, feces, milk, and blood samples were collected. Daily rumination times and milk yield were recorded. Data were analyzed through repeated measures mixed models. Compared to the CTR group, AL cows tended to show reduced production of volatile fatty acids in the rumen with acetate proportion that tended to be higher and valerate proportion that was lower. Moreover, Aloe supplementation caused a reduction in fecal dry matter. At the end of drying-off, AL cows presented better liver function, as suggested by higher paraoxonase plasma concentrations at 7 DFD, higher glucose, and lower urea, but showed increased reactive oxygen metabolites. Aloe supplementation at dry-off ameliorated inflammatory status after calving (lower haptoglobin and ceruloplasmin levels), and improved milk yield in the first weeks of subsequent lactation, without influencing milk composition, SCC, and incidence of intramammary infections. These results confirmed the positive effects of Aloe administration on liver function in dairy cows but indicate the need for further studies investigating the effects of Aloe on rumen fermentation profile and oxidative status.

Evaluation of circulating leukocyte transcriptome and its relationship with immune function and blood markers in dairy cows during the transition period.

Dairy cows during the transition period are faced with important physiological changes which include a dysfunctional immune system and an increased inflammatory state. New data are necessary to understand the key factors involved in the immune system regulation. Six dairy cows were sampled during transition period to investigate the leukocyte transcriptome changes and its relationship with blood biomarkers. Blood samples were collected at - 20 ± 2, - 3 ± 1, 3, and 7 days from parturition (DFP). Leukocyte transcriptome was analyzed by deep sequencing technology (Hiseq1000 Illumina, USA). Plasma was analyzed for metabolic biomarkers. Differentially expressed genes (DEG) were used to run an enrichment analysis through the Dynamic Impact Approach (DIA). Considering - 20 DFP as references time, the main KEGG impacted pathways were activated before calving (- 3 DFP) and were connected to lipid metabolism, lipid transport in plasma, and phagosome. The greatest differences were found after parturition with 281 DEG (179 upregulated and 102 downregulated). The activated pathways were mainly related to immunity and endocrine aspects, while metabolic pathways related to lipid and amino acid metabolism were inhibited. Plasma BHBA had a substantial inhibitory impact on KEGG pathways related to DNA replication and cell cycle, while plasma IL-1ß had an inhibitory impact on fatty acid elongation in mitochondria and an activated impact in several pathways related to cellular energy metabolism. Overall, this study confirmed that many changes in lipid metabolism and immune competence of the circulating leukocytes occurred in dairy cow around calving. Interestingly, BHBA and IL-1ß connected with the transcriptome.

Differential effects of coconut versus soy oil on gut microbiota composition and predicted metabolic function in adult mice.

BACKGROUND: Animal studies show that high fat (HF) diet-induced gut microbiota contributes to the development of obesity. Oil composition of high-fat diet affects metabolic inflammation differently with deleterious effects by saturated fat. The aim of the present study was to examine the diversity and metabolic capacity of the cecal bacterial community in C57BL/6 N mice administered two different diets, enriched respectively with coconut oil (HFC, high in saturated fat) or soy oil (HFS, high in polyunsaturated fat). The relative impact of each hypercaloric diet was evaluated after 2 and 8 weeks of feeding, and compared with that of a low-fat, control diet (LF). RESULTS: The HFC diet induced the same body weight gain and fat storage as the HFS diet, but produced higher plasma cholesterol levels after 8 weeks of treatment. At the same time point, the cecal microbiota of HFC diet-fed mice was characterized by an increased relative abundance of Allobaculum, Anaerofustis, F16, Lactobacillus reuteri and Deltaproteobacteria, and a decreased relative abundance of Akkermansia muciniphila compared to HFS mice. Comparison of cecal microbiota of high-fat fed mice versus control mice indicated major changes that were shared between the HFC and the HFS diet, including the increase in Lactobacillus plantarum, Lutispora, and Syntrophomonas, while some other shifts were specifically associated to either coconut or soy oil. Prediction of bacterial gene functions showed that the cecal microbiota of HFC mice was depleted of pathways involved in fatty acid metabolism, amino acid metabolism, xenobiotic degradation and metabolism of terpenoids and polyketides compared to mice on HFS diet. Correlation analysis revealed remarkable relationships between compositional changes in the cecal microbiota and alterations in the metabolic and transcriptomic phenotypes of high-fat fed mice. CONCLUSIONS: The study highlights significant differences in cecal microbiota composition and predictive functions of mice consuming a diet enriched in coconut vs soy oil. The correlations established between specific bacterial taxa and various traits linked to host lipid metabolism and energy storage give insights into the role and functioning of the gut microbiota that may contribute to diet-induced metabolic disorders.

Dietary supplement of conjugated linoleic acids or polyunsaturated fatty acids suppressed the mobilization of body fat reserves in dairy cows at early lactation through different pathways.

To investigate the metabolic changes in the adipose tissue (AT) of dairy cows under milk fat depression (MFD), 30 cows were randomly allocated to a control diet, a conjugated linoleic acid (CLA)-supplemented diet, or a high-starch diet supplemented with a mixture of sunflower and fish oil (2:1; as HSO diet) from 1 to 112 d in milk. Performance of animals, milk yield, milk composition, energy balance, and blood metabolites were measured during lactation. Quantitative PCR analyses were conducted on the AT samples collected at wk 3 and 15 of lactation. The CLA and HSO diets considerably depressed milk fat yield and milk fat content at both wk 3 and 15 in the absence of significant changes in milk protein and lactose contents. In addition, the HSO diet lowered milk yield at wk 15 and decreased dry matter intake of cows from wk 3 to 15. Compared with the control, both CLA and HSO groups showed reduced body weight loss, improved energy balance, and decreased plasma concentrations of nonesterified fatty acids and ß-hydroxybutyrate at early lactation. The gene expression analyses reflected suppressed lipolysis in AT of the CLA and HSO groups compared with the control at wk 3, as suggested by the downregulation of hormone-sensitive lipase and fatty acid binding protein 4 and the upregulation of perilipin 2. In addition, the HSO diet promoted lipogenesis in AT at wk 15 through the upregulation of 1-acylglycerol-3-phosphate O-acyltransferase 2, mitochondrial glycerol-3-phosphate acyltransferase, perilipin 2, and peroxisome proliferator-activated receptor γ. The CLA diet likely regulated insulin sensitivity in AT as it upregulated the transcription of various genes involved in insulin signaling, inflammatory responses, and ceramide metabolism, including protein kinase B2, nuclear factor κ B1, toll-like receptor 4, caveolin 1, serine palmitoyltransferase long chain base subunit 1, and N-acylsphingosine amidohydrolase 1. In contrast, the HSO diet resulted in little or no change in the pathways relevant to insulin sensitivity. In conclusion, the CLA and HSO diets induced a shift in energy partitioning toward AT instead of mammary gland during lactation through the regulation of different pathways.

Assessment of the main plasma parameters included in a metabolic profile of dairy cow based on Fourier Transform mid-infrared spectroscopy: preliminary results.

BACKGROUND: Although a metabolic profile represents a valid tool utilized in dairy herds to determine abnormalities in blood chemistry related to an increased risk of production diseases, there are no studies on application of Fourier Transform mid-infrared (FT-MIR) spectroscopy. This study assesses the potential application of FT-MIR to analyze the main blood biochemical parameters included in the metabolic profile of dairy cows. Infrared transmission spectra were acquired for 35 plasma samples (two replicates on each sample) of Italian Friesian dairy cows (14 primiparous and 21 pluriparous), all without clinical events, and at different stages of lactation, although mainly in the transition phase. Each sample was also analyzed independently using accepted reference clinical chemical methods and these results were used as calibrating values to perform predictive models by PLS method using cross validation. RESULTS: Measured blood parameters concentrations were all within the reference ranges reported for healthy dairy cows. The number of extracted factors with the PLS procedure for each prediction model ranged between 3 and 7. The coefficient of determination (R(2)) of the prediction models ranged between 0.1 to values close to 1. R(2) values greater than 0.9 were observed for the prediction models of total cholesterol, total protein, globulin, and albumin; values between 0.75 and 0.9 were observed for urea, NEFA, and total bilirubin, while values of R(2) lower than 0.6 were observed for all minerals and for enzyme activity. The range error ratio (RER) and prediction to deviation (RPD) ranged from 5.1 to 43.8 and from 1 to 13.8 for RER and RPD, respectively. Values of RPD greater than 5 were observed for total cholesterol, total protein, albumin, and globulin. RPD ranged between 2 and 5 for the prediction models of urea, NEFA, and total bilirubin, while RPD and RER were low for minerals and enzyme activities. CONCLUSIONS: Although the results of this study require further validation, the use of FT-MIR spectroscopy was possible and provides fairly accurate measurement of various parameters of great importance in the evaluation of the metabolic and inflammatory status in dairy cows.

Gut response induced by weaning in piglet features marked changes in immune and inflammatory response.

At weaning, piglets are exposed to many stressors, such as separation from the sow, mixing with other litters, end of lactational immunity, and a change in their environment and gut microbiota. The sudden change of feeding regime after weaning causes morphological and histological changes in the small intestine which are critical for the immature digestive system. Sixteen female piglets were studied to assess the effect of sorbic acid supplementation on the small intestine tissue transcriptome. At weaning day (T0, piglet age 28 days), four piglets were sacrificed and ileal tissue samples collected. The remaining 12 piglets were weighed and randomly assigned to different postweaning (T5, piglet age 33 days) diets. Diet A (n = 6) contained 5 g/kg of sorbic acid. In diet B (n = 6), the organic acids were replaced by barley flour. Total RNA was isolated and then hybridized to CombiMatrix CustomArray™ 90-K platform microarrays, screening about 30 K genes. Even though diet had no detectable effect on the transcriptome during the first 5 days after weaning, results highlighted some of the response mechanisms to the stress of weaning occurring in the piglet gut. A total of 205 differentially expressed genes were used for functional analysis using the bioinformatics tools BLAST2GO, Ingenuity Pathway Analysis 8.0, and Dynamic Impact Approach (DIA). Bioinformatic analysis revealed that apoptosis, RIG-I-like, and NOD-like receptor signaling were altered as a result of weaning. Interferons and caspases gene families were the most activated after weaning in response to piglets to multiple stressors. Results suggest that immune and inflammatory responses were activated and likely are a cause of small intestine atrophy as revealed by a decrease in villus height and villus/crypt ratio.

Ready-to-Use Supplementary-Food Biscuit Production with Low-Cost Ingredients for Malnourished Children in Sub-Saharan Africa.

In Africa, the number of children under 5 years old who suffer from stunting and wasting are, respectively, 61.4 and 12.1 million, and to manage situations like these, emergency food products like RUTF and RUSF (ready-to-use therapeutic/supplementary food) are very useful. The aim of this study was to develop an RUSF biscuit using the low-cost food resources usually present in Sub-Saharan Africa (Burundi and the DRCongo in our case study); we conducted chemical characterization, nutritional evaluation, and a stability trial simulating the usual storage conditions in a rural context to demonstrate that RUSF can be functional also using low-cost ingredients and a simple method of production. The obtained recipes showed good potential in supplying protein integration-17.81% (BUR) and 16.77% (CON) (% as food) were the protein contents-and the protein digestibility values were very high (BUR: 91.72%; CON: 92.01%). Moreover, 30% of the daily requirement was achieved with less than 50 g of both recipes in all the considered ages. Finally, a good shelf-life was demonstrated during the 35-day testing period at 30 °C, considering moisture, texture, and lipid oxidation evolution. Recipes like these, with appropriate changes, could be very useful in all contexts where child malnutrition is a serious problem.

Structural and functional analysis of the active cow rumen's microbial community provides a catalogue of genes and microbes participating in the deconstruction of cardoon biomass.

BACKGROUND: Ruminal microbial communities enriched on lignocellulosic biomass have shown considerable promise for the discovery of microorganisms and enzymes involved in digesting cell wall compounds, a key bottleneck in the development of second-generation biofuels and bioproducts, enabling a circular bioeconomy. Cardoon (Cynara cardunculus) is a promising inedible energy crop for current and future cellulosic biorefineries and the emerging bioenergy and bioproducts industries. The rumen microbiome can be considered an anaerobic "bioreactor", where the resident microbiota carry out the depolymerization and hydrolysis of plant cell wall polysaccharides (PCWPs) through the catalytic action of fibrolytic enzymes. In this context, the rumen microbiota represents a potential source of microbes and fibrolytic enzymes suitable for biofuel production from feedstocks. In this study, metatranscriptomic and 16S rRNA sequencing were used to profile the microbiome and to investigate the genetic features within the microbial community adherent to the fiber fractions of the rumen content and to the residue of cardoon biomass incubated in the rumen of cannulated cows. RESULTS: The metatranscriptome of the cardoon and rumen fibre-adherent microbial communities were dissected in their functional and taxonomic components. From a functional point of view, transcripts involved in the methanogenesis from CO2 and H2, and from methanol were over-represented in the cardoon-adherent microbial community and were affiliated with the Methanobrevibacter and Methanosphaera of the Euryarchaeota phylum. Transcripts encoding glycoside hydrolases (GHs), carbohydrate-binding modules (CBMs), carbohydrate esterases (CEs), polysaccharide lyases (PLs), and glycoside transferases (GTs) accounted for 1.5% (6,957) of the total RNA coding transcripts and were taxonomically affiliated to major rumen fibrolytic microbes, such as Oscillospiraceae, Fibrobacteraceae, Neocallimastigaceae, Prevotellaceae, Lachnospiraceae, and Treponemataceae. The comparison of the expression profile between cardoon and rumen fiber-adherent microbial communities highlighted that specific fibrolytic enzymes were potentially responsible for the breakdown of cardoon PCWPs, which was driven by specific taxa, mainly Ruminococcus, Treponema, and Neocallimastigaceae. CONCLUSIONS: Analysis of 16S rRNA and metatranscriptomic sequencing data revealed that the cow rumen microbiome harbors a repertoire of new enzymes capable of degrading PCWPs. Our results demonstrate the feasibility of using metatranscriptomics of enriched microbial RNA as a potential approach for accelerating the discovery of novel cellulolytic enzymes that could be harnessed for biotechnology. This research contributes a relevant perspective towards degrading cellulosic biomass and providing an economical route to the production of advanced biofuels and high-value bioproducts.

Stress and inflammatory response of cows and their calves during peripartum and early neonatal period.

Stress, inflammatory response, and their relationship were investigated in Simmental cows during the transition period (N = 8; 5 multiparous and 3 primiparous) and in their calves (N = 8; 5 heifers and 3 bulls). From cows, blood was collected at days -21 (±4), 0, +1, +7, and +21 days relative to calving. From calves, blood was collected after birth before colostrum intake (0) and then at 1, 7, and 15 days of age. Cortisol, Interleukin 6 (IL-6) and haptoglobin concentration was assessed by ELISA technique; white blood cells (WBC) were assessed using an ADVIA 2120 Hematology System machine. One-way ANOVA showed an effect of time for all the investigated parameters (P < 0.001) except for lymphocytes in peripartal cows. At calving and 1 d after, cortisol concentration was negatively correlated with levels of IL-6, WBC, and monocytes, whereas levels of IL-6 were positively correlated with WBC, neutrophils, and monocytes count. Cortisol, IL-6, haptoglobin, WBC and all leukocyte populations were affected by the age of neonatal calves (P < 0.001) except for neutrophils. A negative correlation between cortisol and IL-6, neutrophils, monocytes and haptoglobin was found at 15 days of age. A positive correlation between IL-6 and haptoglobin at day 15 of age, and with neutrophils and monocytes at days 7 and 15 of age was found. A positive correlation was obtained between cortisol levels measured in cows around calving and those obtained in calves after birth before colostrum intake (r = 0.83), and between IL-6 concentrations obtained from cows at calving and 1 d after and those obtained in calves at day 1 of age, after the colostrum intake (r = 0.93 and 0.79, respectively). The study suggests that immune function of peripartal cows is in an active state and that, in addition to other well-known factors driving the changes of parameters herein investigated, cortisol could have a role in the immune-modulatory adjustment during peripartum in cows. Furthermore, it can be hypothesized that cortisol is transferred from the cow to newborn calf through the placenta only and not through colostrum, whereas IL-6 levels in calves during the 24 h after birth seem to be influenced by IL-6 values measured in cows around calving due to its transfer through colostrum.

Whole cottonseed inclusion in starter feeds improves performance, inflammometabolic profile, and rumination behavior in Holstein dairy calves.

The high energy, protein, and fiber contents of whole cottonseed make it a potential candidate for the inclusion in calf starters to promote the rumen development. This study aimed at assessing whether the inclusion of whole cottonseed in the starter would affect performance, metabolic profile, and rumination time in Holstein dairy calves. From 2 to 55 d of age, 12 heifer calves were fed a constant amount of milk replacer twice daily (8 L/d), whereas from 56 to 65 d (weaning) milk replacer was gradually reduced (from 4 to 1 L/d) and fed in a single meal. Calves were blocked by birth body weight and % Brix of colostrum received and randomly assigned to 1 out of 2 dietary treatments: (1) control starter (CTR); (2) starter with 8% inclusion of whole cottonseed (WCS). Treatments were fed for ad libitum intake. From d 56, TMR and hay were offered ad libitum. At 0, 2, 7, 21, 65, and 80 d, BW was measured and blood samples were collected. Feed intake and rumination time were automatically recorded. Compared with CTR, WCS calves were heavier at weaning and after weaning, and consumed more starter from 59 to 72 d. In the immediate postweaning (from 66 to 72 d of age), rumination time increased more in WCS calves. Overall, WCS calves had greater plasma glucose, ß-carotene, and retinol concentrations, whereas ceruloplasmin and myeloperoxidase were lower. Calves in the WCS group had greater glucose concentration at 21 and 65 d and lower urea at 65 d (weaning). Plasma ß-carotene concentration was greater at 65 and 80 d in calves of the WCS group compared with CTR calves. At 80 d, WCS calves had lower plasma alkaline phosphatase and greater ß-hydroxybutyrate, paraoxonase, and tocopherol. These results suggest that inclusion of WCS in the calf starter might be beneficial for rumen development, leading to greater feed intake and BW. Moreover, WCS inclusion was associated with lower oxidative stress and inflammation, improved energy metabolism and liver functionality, and likely quicker rumen development, as might be indicated by the higher plasma ß-hydroxybutyrate and rumination time. These changes occurred mainly after weaning, when no differences in starter intake and average daily gain were detected, suggesting a better efficiency of nutrient utilization at this age.

Effect of Different Anticoagulant Agents on Immune-Related Genes in Leukocytes Isolated from the Whole-Blood of Holstein Cows.

Anticoagulants, such as ethylenediaminetetraacetic acid (EDTA), sodium citrate (Na-citrate), or heparin are normally used in hematological clinical tests to prevent coagulation. Although anticoagulants are fundamental for the correct application of clinical tests, they produce adverse effects in different fields, such as those involving specific molecular techniques; for instance, quantitative real time polymerase chain reactions (qPCR) and gene expression evaluation. For this reason, the aim of this study was to evaluate the expression of 14 genes in leukocytes that were isolated from the blood of Holstein cows, and which were collected in Li-heparin, K-EDTA, or Na-citrate tubes; then, they were analyzed using qPCR. Only the SDHA gene showed a significant dependence (p ≤ 0.05) on the anticoagulant that was used with the lowest expression; this was observed in Na-Citrate after being compared with Li-heparin and K-EDTA (p < 0.05). Although a variation in transcript abundance with the three anticoagulants was observed in almost all the investigated genes, the relative abundance levels were not statistically significant. In conclusion, the qPCR results were not influenced by the presence of the anticoagulant; thus, we had the opportunity to choose the test tube that was used in the experiment without interfering effects impacting the gene expression levels caused by the anticoagulant.

Maternal treatment with pegbovigrastim influences growth performance and immune-metabolic status of calves during the pre-weaning period.

This study aimed to investigate the immune-metabolic status and growth performance of Simmental calves born from cows subjected to pegbovigrastim administration 7 days before calving. Eight calves born from cows subjected to pegbovigrastim administration (PEG group) and 9 calves born from untreated cows (CTR group) were used. Growth measurements and blood samples were collected from birth to 60 d of age. The PEG group had lower body weight from 28 up to 60 d of age (P < 0.01), lower heart girth (P < 0.05), lower weekly and total average daily gain values (P < 0.05) than the CTR group throughout the monitoring period. A decrease in milk replacer (MR) intake was observed in the PEG group compared with the CTR group around 20-28 d of age (P < 0.01). The PEG group had lower values of γ-glutamyl transferase (GGT) at d 1 of age (P < 0.05), Zn at 21 and 28 d of age (P < 0.05), hemoglobin, MCH and MCHC at 54 and 60 d of age (P < 0.01), and higher urea concentration at 21 and 28 d of age (P < 0.05) compared with the CTR group. Lower values of retinol (P < 0.05), tocopherol (P < 0.01), mean myeloperoxidase index (P < 0.05) and higher total reactive oxygen metabolites (P < 0.05) and myeloperoxidase (P < 0.05) were also detected in the PEG group. In light of the results gathered in the current study, it can be speculated that activation of the cow's immune system by pegbovigrastim could have influenced the immune competence, growth performance as well as the balance between oxidant and antioxidant indices of the newborn calf.

The Effect of Feeding a Total Mixed Ration with an ad libitum or Restricted Pelleted Starter on Growth Performance, Rumination Behavior, Blood Metabolites, and Rumen Fermentation in Weaning Holstein Dairy Calves.

The aim of the current study was to evaluate the effect of the starter restriction and of the ad libitum TMR (total mixed ration) inclusion on intake, growth performance, rumination time (RT), and health condition of Holstein dairy calves during weaning. We randomly assigned thirty female Holstein calves (with an average weight of 38.5 ± 1.96 kg at birth) to one of three treatments. From 21 days of age, the calves were fed one of three treatments as follows: a control diet (CTR) with an ad libitum calf starter but without TMR; Treatment 1 diet (TRT1) with both an ad libitum calf starter and ad libitum TMR; Treatment 2 diet (TRT2) with ad libitum TMR and a restricted amount of a calf starter (50% of the intake recorder in the control group day by day). Calves in the TRT2 group, between 56 and 63 days of age, had a lower body weight (80.1; 79.5; 75.6 kg for the CTR, TRT1, and TRT2 groups, respectively) compared with CTR and TRT1 calves. This outcome is ascribed to the average daily gain (0.759; 0.913; 0.508 kg/day for the CTR, TRT1, and TRT2 groups, respectively), resulting also in TRT2 being lower than CTR or TRT1 calves. The inclusion of ad libitum TMR increased the rumination time, especially after weaning (15.28 min/h, 18.38 min/h, and 18.95 min/h for the CTR, TRT1, and TRT2 groups, respectively). Concerning the rumen metabolism and inflammometabolic response, overall, no differences were observed between the three dietary treatments. In conclusion, the results indicated that a TMR could partially replace a calf starter in weaning dairy calves, since neither growth performance nor health status were impaired. In addition, providing TMR (with or without concentrate restriction) led to a better rumen development and likely a better rumen fermentation efficiency in post-weaning.

Short-term modifications in the distal gut microbiota of weaning mice induced by a high-fat diet.

The gut microbiota has been shown to be involved in host energy homeostasis and diet-induced metabolic disorders. To gain insight into the relationships among diet, microbiota and the host, we evaluated the effects of a high-fat (HF) diet on the gut bacterial community in weaning mice. C57BL/6 mice were fed either a control diet or a diet enriched with soy oil for 1 and 2 weeks. Administration of the HF diet caused an increase in plasma total cholesterol levels, while no significant differences in body weight gain were observed between the two diets. Denaturing gradient gel electrophoresis (DGGE) profiles indicated considerable variations in the caecal microbial communities of mice on the HF diet, as compared with controls. Two DGGE bands with reduced intensities in HF-fed mice were identified as representing Lactobacillus gasseri and an uncultured Bacteroides species, whereas a band of increased intensity was identified as representing a Clostridium populeti-related species upon sequencing. Quantitative real-time PCR confirmed a statistically significant 1-log decrease in L. gasseri cell numbers after HF feeding, and revealed a significantly lower level of Bifidobacterium spp. in the control groups after 1 and 2 weeks compared with that in the HF groups. These alterations of intestinal microbiota were not associated with caecum inflammation, as assessed by histological analysis. The observed shifts of specific bacterial populations within the gut may represent an early consequence of increased dietary fat.

Effects of an Intravenous Infusion of Emulsified Fish Oil Rich in Long-Chained Omega-3 Fatty Acids on Plasma Total Fatty Acids Profile, Metabolic Conditions, and Performances of Postpartum Dairy Cows During the Early Lactation.

A group of 10 multiparous Italian Holstein cows were housed in individual tied stalls and infused with 150 ml of saline (CTR; 5 cows), or of 10% solution rich in long-chained omega-3 fatty acids (n3FA; 5 cows) at 12, 24, and 48 h after calving. From -7 to 21 days from calving (DFC), the body condition score, body weight, dry matter intake (DMI), and milk yield were measured, blood samples were collected to assess the plasma fatty acids (FA) and metabolic profiles, and milk samples were collected to assess the milk composition. Data underwent a mixed model for repeated measurements, including the treatment and time and their interactions as fixed effects. Plasma FA profile from n3FA cows had lower myristic and higher myristoleic proportions, higher cis-11,14-eicosadienoic acid and monounsaturated FA proportions at 3 DFC, and lower cis-10-pentadecanoic proportion at 10 DFC. Besides these, n3FA cows had higher eicosapentaenoic (EPA) and docosahexaenoic (DHA) proportions (1.09 vs. 0.71 and 0.33 vs. 0.08 g/100 g), confirming the effectiveness of the infusion in elevating plasma availability of these FA. The plasma metabolic profile from n3FA cows revealed a tendency toward a lower concentration of reactive oxygen metabolites at 1 DFC and lower haptoglobin at 2 and 3 DFC, reflecting a mitigated inflammatory state. Furthermore, n3FA cows had a higher DMI during the first week of lactation. Higher DMI of n3FA could account for the changes detected on their plasma FAs, the higher milk yield they had at 1 and 2 DFC, the reduced lactose and urea nitrogen content in their milk. Higher DMI could also account for the lower plasma urea that n3FA cows had at 1 and 2 DFC, suggesting a lower amount of endogenous amino acids deserved to gluconeogenic fate. Milk from n3FA cows had lower rennet clotting time and higher curd firmness, which is probably driven by a higher EPA and DHA inclusion in the milk fat. Together, these outcomes suggest that the infusion exerts a short-term anti-inflammatory action on dairy cows at the onset of lactation.

Effects of Weaning Age on Plasma Biomarkers and Growth Performance in Simmental Calves.

Weaning plays a key role in health status and future performance of calves. The aim of this study was to investigate the effects of weaning age (Wa), early (45 d, EW) or conventional (60 d, CW), on growth performance and metabolic profile of ten Simmental calves (5 EW and 5 CW calves). Daily intake of milk and calf starter was recorded. Blood samples and measurements of body weight (BW), heart girth (HG), and wither height (WH) were collected at −25, −15, 0, 6, and 20 days relative to weaning. Growth performances (BW, HG, WH) were affected by Wa, resulting lower in EW calves compared with CW calves (p < 0.05). Average daily gain was affected by overall Wa and Time but also by the interaction Wa × Time (p < 0.05). EW calves had lower paraoxonase and higher oxidation protein products levels, lower glucose levels in the post-weaning period, lower Ca and cholesterol levels at 20 d after weaning, and higher GGT activity at −25 d from weaning (p < 0.05). A significant interaction effect between Wa and Time was reached for glucose, Ca, cholesterol. In conclusion, weaning Simmental calves at approximately six weeks of age might not affect inflammatory status and liver functionality after weaning. As secondary outcome, even though the low number of animals could represent a limitation, the average daily gain obtained by Simmental calves weaned at 45 d supported this strategy (despite the lower body weight at weaning and after was due only to the age difference of 15 days). Hence, in order to reduce rearing costs, early weaning for Simmental calves (dual-purpose breed, milk and beef) might not jeopardize calf development, as long as calves can reach body gains as reported in the present study.

Associations between Milk Fatty Acid Profile and Body Condition Score, Ultrasound Hepatic Measurements and Blood Metabolites in Holstein Cows.

Dairy cows have high incidences of metabolic disturbances, which often lead to disease, having a subsequent significant impact on productivity and reproductive performance. As the milk fatty acid (FA) profile represents a fingerprint of the cow's nutritional and metabolic status, it could be a suitable indicator of metabolic status at the cow level. In this study, we obtained milk FA profile and a set of metabolic indicators (body condition score, ultrasound liver measurements, and 29 hematochemical parameters) from 297 Holstein-Friesian cows. First, we applied a multivariate factor analysis to detect latent structure among the milk FAs. We then explored the associations between these new synthetic variables and the morphometric, ultrasonographic and hematic indicators of immune and metabolic status. Significant associations were exhibited by the odd-chain FAs, which were inversely associated with ß-hydroxybutyrate and ceruloplasmin, and positively associated with glucose, albumin, and γ-glutamyl transferase. Short-chain FAs were inversely related to predicted triacylglycerol liver content. Rumen biohydrogenation intermediates were associated with glucose, cholesterol, and albumin. These results offer new insights into the potential use of milk FAs as indicators of variations in energy and nutritional metabolism in early lactating dairy cows.

In-line near-infrared analysis of milk coupled with machine learning methods for the daily prediction of blood metabolic profile in dairy cattle.

Precision livestock farming technologies are used to monitor animal health and welfare parameters continuously and in real time in order to optimize nutrition and productivity and to detect health issues at an early stage. The possibility of predicting blood metabolites from milk samples obtained during routine milking by means of infrared spectroscopy has become increasingly attractive. We developed, for the first time, prediction equations for a set of blood metabolites using diverse machine learning methods and milk near-infrared spectra collected by the AfiLab instrument. Our dataset was obtained from 385 Holstein Friesian dairy cows. Stacking ensemble and multi-layer feedforward artificial neural network outperformed the other machine learning methods tested, with a reduction in the root mean square error of between 3 and 6% in most blood parameters. We obtained moderate correlations (r) between the observed and predicted phenotypes for γ-glutamyl transferase (r = 0.58), alkaline phosphatase (0.54), haptoglobin (0.66), globulins (0.61), total reactive oxygen metabolites (0.60) and thiol groups (0.57). The AfiLab instrument has strong potential but may not yet be ready to predict the metabolic stress of dairy cows in practice. Further research is needed to find out methods that allow an improvement in accuracy of prediction equations.

Gene network expression of whole blood leukocytes in dairy cows with different milk yield at dry-off.

Dairy cows at dry-off undergo several management and physiological changes, resulting in alterations in plasma biomarkers of inflammation, oxidative stress, and immune system. High milk yield at the end of lactation exacerbates these responses. The underlying mechanism of these changes has yet to be elucidated. We hypothesized altered leukocyte gene expression after dry-off and different responses in cows with different milk yield. Thirteen Holstein dairy cows were sampled at the turn of dry-off to investigated whole blood leukocyte gene expression and were grouped according to the average milk yield during the last week of lactation: low (< 15 kg/d) and high milk yield (> 15 kg/d). Blood samples were collected in PAXgene tubes (Preanalytix, Hombrechtikon, Switzerland) at -7, 7, and 34 days from dry-off (DFD) to measure mRNA abundance of 37 genes. Normalized gene abundance data were subjected to MIXED model ANOVA (SAS Institute Inc., Cary, NC). Compared with -7 DFD, at 7 DFD RNA abundance of lipoxygenase genes (ALOX5, ALOX15) and myeloperoxidase (MPO) increased, and that of the antioxidant gene (SOD2) decreased. Meanwhile, genes related to recognition and immune mediation (CD16, MYD88, TLR2), migration and cell adhesion (CX3CR1, ITGAL, ITGB2, TLN1), and the antimicrobial gene MMP9 were downregulated at 7 or 34 DFD, whereas the antimicrobial IDO1 gene was upregulated. Compared with low-producing cows, cows with high milk yield at dry-off cows had upregulated expression of the pro-inflammatory cytokines IL8 and IL18 and a greater reduction in transcript abundance of the toll-like receptor (TLR) recognition-related gene TLR2. Overall, the dry-off confirmed to be a phase of intense changes, triggering an inflammatory response and somewhat suppressing leukocyte immune function. In cows with high milk yield during the week before dry-off, the inflammatory response was exacerbated.