Responses of dairy cows to weekly individualized feeding strategies for dairy cows regarding their metabolic status.

In dairy farms, cows are commonly fed a mixture of forages and concentrates ad libitum. To improve the energetic status and productivity of dairy cows, individualized feeding strategies have been proposed. One of this strategy is providing supplemental concentrates to adjust the forage-to-concentrate ratio based on factors like individual milk yield or calculated energy balance. This strategy can affect milk production and cow health, though consistent rules for adjustment are lacking. The objectives of this study were to evaluate the effects of an individualized feeding strategy, adjusted weekly based on the body weight gain of dairy cows, on production performance; and to determine if the metabolic status of the cows could be predicted early in lactation to take it into account into the decisions rules of the strategy. A total of 40 multiparous Holstein cows were involved in a 4-mo trial. The cows entered the experiment individually after calving and were initially fed a standard ration with a fixed 3 kg of extra concentrate per day for the first 8 d (on average). The cows were then paired based on calving date, parity (2 or 3), and body weight gain over the initial week. One cow from each pair was assigned to the Standard Feeding (SF) strategy, which continued receiving the fixed ration, while the other was assigned to the Precision Feeding (PF) strategy, which received a variable amount of extra concentrate adjusted weekly based on body weight gain. Measurements included weekly body weight, daily milk yield, and daily intakes of concentrates and forages. Blood samples were collected to measure metabolites (glucose, BHB, NEFA) for metabolic profiling. The results showed no significant differences in overall body weight gain, milk yield, or intakes (concentrates and/or forages). Two metabolic clusters were identified based on blood metabolites (glucose, BHB, NEFA), predicting cows' metabolic status with 90% accuracy. The balanced cluster had higher milk production, feed intake, and lost more body weight than the imbalanced cluster. Alternative variables like body weight gain and total feed intake can be used to predict metabolic clusters, achieving up to 70% accuracy. To conclude, cows fed this precision feeding strategy had similar performances than those fed the standard feeding strategy. Long-term effect of this strategy should be studied. Metabolic profiling predicted cows' metabolic status suggesting its potential for enhancing individualized feeding decisions.

Cs diffusion mechanisms in UO2 investigated by SIMS, TEM, and atomistic simulations.

Experimental investigations and atomistic simulations are combined to study the cesium diffusion processes at high temperature in UO2. After 133Cs implantation in UO2 samples, diffusion coefficients are determined using the depth profile evolution after annealing as measured by secondary ion mass spectrometry. An activation energy of 1.8 ± 0.2 eV is subsequently deduced in the 1300-1600 °C temperature range. Experimental results are compared to nudged elastic band simulations performed for different atomic paths including several types of uranium vacancy defects. Activation energies ranging from 0.49 up to 2.34 eV are derived, showing the influence of the defect (both in terms of type and concentration) on the Cs diffusion process. Finally, molecular dynamics simulations are performed, allowing the identification of preferential Cs trajectories that corroborate experimental observations.

[Impact of the new European regulation 2017/745 on medical devices on hospital pharmacies activity: Example on pharmaceutical supply function within a French university hospital center]. / Impact du nouveau règlement européen 2017/745 relatif aux dispositifs médicaux sur l'activité des pharmacies hospitalières : exemple de la fonction d'approvisionnement pharmaceutique au sein d'un centre hospitalo-universitaire français.

OBJECTIVE: The new European regulation (MDR) on medical devices (MD) is expected to have major impacts on the industrial sector, but also consequences on healthcare professionals. Our objective was to evaluate the impact of the MDR on the supply of MDs in hospital pharmacies at the level of a French university hospital. MATERIAL AND METHODS: We conducted a prospective follow-up of marketing cessations and supply disruptions directly related to the MDR between November 2019 and September 2020. The data were analyzed accounting for the nature of the suppliers (status/size), the nature of the MDs (route/class), and the proposed alternatives. The economic impact on hospital pharmacies was also estimated. RESULTS: Over this period, 96 MD product designations were declared out of stock or in cessation (total of 402 references), of which half corresponded to class IIa MDs, mainly used for surgical procedures. Of the 14 companies concerned (36% French), the majority were manufacturers, of small/medium-size or intermediate size. Substitutions were proposed for only 15 products (15.6%). The cost of pharmaceutical management of these disruptions/marketing cessations was estimated at 3052€. CONCLUSION: Even before the official date of its application, the impacts of the MDR on the supply function of hospital pharmacies are already visible. In the short, medium and long term, prospective monitoring of the impacts, positive or negative, would seem to be justified at the level of manufacturers, healthcare professionals and end users of MDs.

Antibiotic therapy for infectious hemodialysed patients in Bamako: Pharmacokinetic analyses and first improvement suggestions.

Infection which occurs in renal kidney failure patient have to be therapeutically managed immediately and the treatment must be aggressive to be quickly efficient. In Bamako (Mali). Posology adaptation cause a problem in nephrology, especially for the most common used antibiotics to care these infections. Drug dosage is not routinely performed in Bamako. The main objective of this work is to compare anthropometric, clinical and pharmacokinetic profiles and the clinical future between infected hemodialysis patients following an antibiotic therapy in Bamako and Lyon (hospital used as a reference). To reach these objectives, a preliminary punctual study of clinical pharmacokinetic of vancomycin were set up at Bamako, following the personalization therapeutics model from Lyon. Bamako patients' samples were imported to France and dosage analysis were performed at Lyon. BestDose software was used to view and compare complete pharmacokinetic profile. It includes for the first time, in routine, the 50 ml/mn of the renal function during dialyses for 58 patients: 31 for Bamako and 21 for Lyon. The residual concentration at the beginning of the dialysis session was compared. In Bamako, patients are younger, the renal failure is more severe and arteriovenous fistula are never set up, treatments are limited in dose and in duration; the residual concentration before the dialyses are too low; as a consequence, infections are rarely quickly reduced and more especially the death linked to these infections are more important (9 in Bamako versus 1 in Lyon). Urgent corrective measures have to be proposed: propose a conciliation between therapeutic requirements formulated within Lyon protocols and the financial ability of the patient, to promote arteriovenous fistula creation as soon as possible, and develop first dose strategy (unfortunately there is often only one dose): a more aggressive dose estimated from simulation profile performed in this study.

TORSAFUF - Surgical exploration for torsion of spermatic cord suspicion and risk factors for unnecessary surgery: Results of a French nationwide retrospective study on 2940 patients.

BACKGROUNDS: Spermatic cord torsion is a frequent urological emergency that mostly concerns teenagers and young adults. This study aimed to determine the clinical and surgical characteristics of young adults who had scrotal exploration for suspected spermatic cord torsion and to identify clinical risk factors associated with needless scrotal exploration. METHODS: We retrospectively collected national data from patients aged 12years and older who underwent a surgical exploration for suspicion of torsion of the spermatic cord between 2005 and 2019 in 17 hospitals. We analyzed demographics, surgical and postoperative characteristics in our population. We compared the cohort according to the intraoperative diagnosis of torsion or not. RESULTS: In total, 2940 had surgical exploration: 1802 (61.3%) patients had torsion of the spermatic cord and 1138 (38.7%) had another diagnosis. In multivariate analysis, age (OR: 1.04; 95% CI: 1.01-1.06; P=0.005), medical history of cryptorchism (OR: 4.14; 95% CI: 1.05-16.31; P=0.042) and VAS pain score (OR: 0.91; 95% CI: 0.83-0.98; P=0.018) were risk factors significantly associated with unnecessary surgical exploration. The rate of complications in the 90days after surgery was 11% in the "torsion" group, and 9.7% in the "non-torsion" group (P=0.28). CONCLUSION: Scrotal exploration without intraoperative diagnosis of torsion was performed in 40% of our cohort. VAS pain score and cryptorchism history can help for the diagnosis but scrotal exploration remains the way to diagnose spermatic cord torsion and should be performed on the slightest suspicion, even after 24hours of symptoms, as the chances for testicular salvage remains around 50%.

Behavioral validation of novel high resolution attention decoding method from multi-units & local field potentials.

The ability to access brain information in real-time is crucial both for a better understanding of cognitive functions and for the development of therapeutic applications based on brain-machine interfaces. Great success has been achieved in the field of neural motor prosthesis. Progress is still needed in the real-time decoding of higher-order cognitive processes such as covert attention. Recently, we showed that we can track the location of the attentional spotlight using classification methods applied to prefrontal multi-unit activity (MUA) in the non-human primates. Importantly, we demonstrated that the decoded (x,y) attentional spotlight parametrically correlates with the behavior of the monkeys thus validating our decoding of attention. We also demonstrate that this spotlight is extremely dynamic. Here, in order to get closer to non-invasive decoding applications, we extend our previous work to local field potential signals (LFP). Specifically, we achieve, for the first time, high decoding accuracy of the (x,y) location of the attentional spotlight from prefrontal LFP signals, to a degree comparable to that achieved from MUA signals, and we show that this LFP content is predictive of behavior. This LFP attention-related information is maximal in the gamma band (30-250 Hz), peaking between 60 to 120 Hz. In addition, we introduce a novel two-step decoding procedure based on the labelling of maximally attention-informative trials during the decoding procedure. This procedure strongly improves the correlation between our real-time MUA and LFP based decoding and behavioral performance, thus further refining the functional relevance of this real-time decoding of the (x,y) locus of attention. This improvement is more marked for LFP signals than for MUA signals. Overall, this study demonstrates that the attentional spotlight can be accessed from LFP frequency content, in real-time, and can be used to drive high-information content cognitive brain-machine interfaces for the development of new therapeutic strategies.

No efficacy of biofield therapy in the treatment of warts of the hands and feet in adults: a randomized controlled trial.

Although biofield therapy is unexplained by scientific evidence, it has been practised for many years in numerous cultures for a variety of medical conditions. This study aimed to determine whether one session of biofield therapy with an experienced practitioner could treat warts on the hands and feet in adults. A single-blind, assessor-blind, placebo-controlled, randomized trial was performed between April 2016 and November 2018. The enrolled participants had at least one wart on the hand or foot that had been present for at least 90 days and they were not using any other therapy for the wart. The primary outcome of this trial was the disappearance of the original wart 3 weeks after session of proximal nontouch biofield therapy vs. a sham session. No original wart had disappeared 3 weeks after intervention (0/64), which made the study impossible to conclude on the primary objective. There were no significant differences between the two groups concerning wart disappearance 3 weeks (P = 0.49) or 6 weeks (P = 0.40) after the intervention. Reduction in wart size at Week 3 tended towards a better result for biofield therapy but this was not significant (P = 0.27). No related adverse effects were observed. The major limitation of this trial was the short follow-up time for measurement of clinical outcome, which did not allow verification of the hypothesis. However, this study shows that 3 weeks after a session of proximal nontouch biofield therapy is an insufficient length of time to assess biofield therapy in comparison with a sham session. Based on this study, biofield therapy cannot be recommended to treat warts within 3 weeks.

Transcription from a gene desert in a melanoma porcine model.

The genetic mechanisms underlying cutaneous melanoma onset and progression need to be further understood to improve patients' care. Several studies have focused on the genetic determinism of melanoma development in the MeLiM pig, a biomedical model of cutaneous melanoma. The objective of this study was to better describe the influence of a particular genomic region on melanoma progression in the MeliM model. Indeed, a large region of the Sus scrofa chromosome 1 has been identified by linkage and association analyses, but the causal mechanisms have remained elusive. To deepen the analysis of this candidate region, a dedicated SNP panel was used to fine map the locus, downsizing the interval to less than 2 Mb, in a genomic region located within a large gene desert. Transcription from this locus was addressed using a tiling array strategy and further validated by RT-PCR in a large panel of tissues. Overall, the gene desert showed an extensive transcriptional landscape, notably dominated by repeated element transcription in tumor and fetal tissues. The transcription of LINE-1 and PERVs has been confirmed in skin and tumor samples from MeLiM pigs. In conclusion, although this study still does not identify a candidate mutation for melanoma occurrence or progression, it highlights a potential role of repeated element transcriptional activity in the MeLiM model.

Effect of the Oxygen Potential on the Mo Migration and Speciation in UO2 and UO2+ x.

Molybdenum is an abundant element produced by fission in the nuclear fuel UO2 in a pressurized water reactor. Although its radiotoxicity is low, this element has a key role on the fuel oxidation and other fission products migration, in particular in the case of an accidental scenario. This study aims to characterize the behavior of molybdenum in uranium dioxide as a function of environmental conditions (oxygen partial pressure, high temperature, UO2 oxidation) typical of an accidental scenario. To do so, molybdenum was introduced in UO2 or UO2+ x pellets by ion implantation, a technique that allows us to mimic the production of Mo in the nuclear fuel by fission. Then, thermal treatments at high temperature and different oxygen partial pressures were carried out. The mobility of Mo in UOX samples was followed by secondary ion mass spectrometry (SIMS), while the Mo chemical speciation was investigated by spectroscopic techniques (XANES, Raman). In parallel, ab initio calculations were performed showing the effect of interstitial oxygen atoms on the Mo incorporation sites in UO2. We show that the Mo mobility is directly connected to its chemical state, which in turn, is linked to the redox conditions. Indeed, under reducing atmosphere, Mo is present in UO2 or UO2+ x samples under a metallic state Mo(0). Its mobility, being quite low, is driven by a diffusion mechanism. An increase of pO2 entails the UO2 and Mo oxidation and, as a consequence, a strong release of this element. We show an increase of the Mo release rate with the increase of the UO2+ x hyper-stoichiometry x. After thermal treatment, Mo remaining in the samples is located in the grains under the MoO2 form. Our experimental results are assessed by ab initio calculations showing that in the presence of oxygen Mo atoms adopt in UO2 a local structure close to the octahedral local geometry of Mo oxides.

Deciphering the genetic regulation of peripheral blood transcriptome in pigs through expression genome-wide association study and allele-specific expression analysis.

BACKGROUND: Efforts to improve sustainability in livestock production systems have focused on two objectives: investigating the genetic control of immune function as it pertains to robustness and disease resistance, and finding predictive markers for use in breeding programs. In this context, the peripheral blood transcriptome represents an important source of biological information about an individual's health and immunological status, and has been proposed for use as an intermediate phenotype to measure immune capacity. The objective of this work was to study the genetic architecture of variation in gene expression in the blood of healthy young pigs using two approaches: an expression genome-wide association study (eGWAS) and allele-specific expression (ASE) analysis. RESULTS: The blood transcriptomes of 60-day-old Large White pigs were analyzed by expression microarrays for eGWAS (242 animals) and by RNA-Seq for ASE analysis (38 animals). Using eGWAS, the expression levels of 1901 genes were found to be associated with expression quantitative trait loci (eQTLs). We recovered 2839 local and 1752 distant associations (Single Nucleotide Polymorphism or SNP located less or more than 1 Mb from expression probe, respectively). ASE analyses confirmed the extensive cis-regulation of gene transcription in blood, and revealed allelic imbalance in 2286 SNPs, which affected 763 genes. eQTLs and ASE-genes were widely distributed on all chromosomes. By analyzing mutually overlapping eGWAS results, we were able to describe putative regulatory networks, which were further refined using ASE data. At the functional level, genes with genetically controlled expression that were detected by eGWAS and/or ASE analyses were significantly enriched in biological processes related to RNA processing and immune function. Indeed, numerous distant and local regulatory relationships were detected within the major histocompatibility complex region on chromosome 7, revealing ASE for most class I and II genes. CONCLUSIONS: This study represents, to the best of our knowledge, the first genome-wide map of the genetic control of gene expression in porcine peripheral blood. These results represent an interesting resource for the identification of genetic markers and blood biomarkers associated with variations in immunity traits in pigs, as well as any other complex traits for which blood is an appropriate surrogate tissue.

Structure and elasticity of composite nanoparticle/polymer nanoshells (hybridosomes®).

Our group recently introduced a new process to synthesize nanoparticle shells of about 100 nm, named "hybridosomes®". Here, the structure and mechanical properties of hybridosomes® made from iron oxide nanoparticles and poly(acrylic acid) are characterized using TEM, AFM and an osmotic compression technique. For the latter, the size distribution of the hybridosomes is monitored by nanoparticle tracking analysis (NTA) in the presence of poly(ethylene glycol)s of different molecular weights. It is found that the size of the hybridosomes® can be tuned from ca. 80 nm to over 110 nm by adjusting the amount of nanoparticles and that their shell consists of a single layer of nanoparticles, with a porous structure. The size of the pores is estimated from osmotic compression experiments at ca. 4000 g mol-1. The mechanical properties are measured both at the ensemble level using size measurements under osmotic pressure and at the single nanoparticle level by atomic force microscopy nanoindentation. Both osmotic and AFM experiments are analyzed in the framework of the continuum elastic theory of thin shells and yield a value of Young's modulus of the order of MPa.

Effect of substituting soybean meal and canola cake with dried distillers grains with solubles at 2 dietary crude protein levels on feed intake, milk production, and milk quality in dairy cows.

Dried distillers grain with solubles (DDGS) is an alternative source of feed protein for dairy cows. Previous studies found that DDGS, based on grains other than corn, can substitute for soybean meal and canola cake as a dietary protein source without reducing milk production or quality. As societal concerns exist, and in many areas strict regulation, regarding nitrogen excretion from dairy cows, the dairy industry has focused on reducing dietary protein level and nitrogen excretion. In the present study, we investigated the use of DDGS as a protein source, at a marginally low dietary crude protein (CP) levels, in a grass-clover and corn silage-based ration. The experiment involved 24 Holstein cows and 2 protein sources (DDGS or soybean-canola mixture) fed at 2 levels of CP (14 or 16%) in a 4 × 4 Latin square design. The aim of this study was to evaluate the effect of both protein source and protein level on feed intake, milk yield, and milk quality. The results indicated that feed intake, milk yield, and protein in milk increased when the protein level in the ration was 16% CP compared with 14%. We found no effect of substituting the soybean-canola mixture with DDGS. Moreover, no sensory problems were observed when comparing fresh milk with stored milk, and milk taste was unaffected by DDGS. Milk from cows fed DDGS had a slightly higher content of linoleic acid and conjugated linoleic acid (CLA 9-11), and lower content of C11 to C17 fatty acids than cows fed diets with the soybean-canola mixture. Cows fed the diets with 16% CP produced milk with higher oleic acids and lower palmitic acid content than cows fed 14% CP diets. To conclude, DDGS can substitute for a soybean-canola mixture without affecting feed intake, milk yield and quality, or sensory quality. Under the conditions of this experiment, feeding 16% CP compared with 14% CP in the ration can increase feed intake and milk production.

Effect of substituting soybean meal and canola cake with grain-based dried distillers grains with solubles as a protein source on feed intake, milk production, and milk quality in dairy cows.

The growth of the bioethanol industry is leading to an increase in the production of coproducts such as dried distillers grains with solubles (DDGS). Both corn-based DDGS and grain-based DDGS (gDDGS; defined as originating from grain sources such as barley, wheat, triticale, or a mix, excluding corn) appear to be relevant sources of feed and protein for dairy cows. To date, most of the studies investigating DDGS have been performed with corn-based DDGS. The objectives of this study were to determine the effects of the proportion of gDDGS in the diet on feed intake, milk production, and milk quality. The present experiment involved 48 Holstein cows in a replicated 3 × 3 Latin square design with 3 grass-based dietary treatments consisting of 4, 13.5, and 23% gDDGS on a dry matter (DM) basis (L, M, and H, respectively) as a replacement for a concentrate mix. The concentrate mix consisted of soybean meal, canola cake, and beet pulp. Dry matter intake and energy-corrected milk yield were not affected by the proportion of gDDGS in the diet. Daily milk yield decreased with the H diet compared with the L and M diets. The percentage of fat in milk was higher when cows were fed the H diet compared with the L and M diets, whereas milk fat yield was not affected by dietary treatment. The M diet had a higher percentage of protein in milk compared with the L and H diets. Milk protein yield was similar for the L and M diets; however, it decreased for the H diet. Milk taste was not affected by the proportion of gDDGS in the diet or when milk was stored for 7 d. Linoleic acid and conjugated linoleic acid cis-9,trans-11 in milk increased with increasing proportion of gDDGS. To conclude, gDDGS can replace soybean meal and canola cake as a protein source in the diet of dairy cows. Up to 13.5% of the diet may consist of gDDGS without negatively affecting milk production, milk quality, or milk taste. When gDDGS represents 23% of dietary DM, milk production is reduced by 1.6 kg/d, whereas energy-corrected milk production is numerically reduced by 1 kg.

Feasibility of measuring renal blood flow by phase-contrast magnetic resonance imaging in patients with autosomal dominant polycystic kidney disease.

OBJECTIVES: Renal blood flow (RBF) has been shown to predict disease progression in autosomal dominant polycystic kidney disease (ADPKD). We investigated the feasibility and accuracy of phase-contrast RBF by MRI (RBFMRI) in ADPKD patients with a wide range of estimated glomerular filtration rate (eGFR) values. METHODS: First, we validated RBFMRI measurement using phantoms simulating renal artery hemodynamics. Thereafter, we investigated in a test-set of 21 patients intra- and inter-observer coefficient of variation of RBFMRI. After validation, we measured RBFMRI in a cohort of 91 patients and compared the variability explained by characteristics indicative for disease severity for RBFMRI and RBF measured by continuous hippuran infusion. RESULTS: The correlation in flow measurement using phantoms by phase-contrast MRI was high and fluid collection was high (CCC=0.969). Technical problems that precluded RBFMRI measurement occurred predominantly in patients with a lower eGFR (34% vs. 16%). In subjects with higher eGFRs, variability in RBF explained by disease characteristics was similar for RBFMRI compared to RBFHip, whereas in subjects with lower eGFRs, this was significantly less for RBFMRI. CONCLUSIONS: Our study shows that RBF can be measured accurately in ADPKD patients by phase-contrast, but this technique may be less feasible in subjects with a lower eGFR. KEY POINTS: Renal blood flow (RBF) can be accurately measured by phase-contrast MRI in ADPKD patients. RBF measured by phase-contrast is associated with ADPKD disease severity. RBF measurement by phase-contrast MRI may be less feasible in patients with an impaired eGFR.

Milk yield and estrous behavior during eight consecutive estruses in Holstein cows fed standardized or high energy diets and grouped according to live weight changes in early lactation.

Cows managed for extended lactation go through several estruses before rebreeding. The aims of this study were (1) to quantify the effect of the first 8 estruses after calving on milk yield, milking frequency, and estrous behavioral activity, and (2) to determine the effects of early lactation live weight gain (LWG) as an indication of energy balance on milk yield, plasma insulin-like growth factor 1 (IGF-1) concentration, estrous behavioral activity, interval from calving to first estrus, between-estrus intervals, and pregnancy risk. Milk yield, live weight, and estrous behavioral activity were measured daily in 62 Holstein cows, 17 primiparous and 45 multiparous, managed for an 18-mo calving interval. Blood plasma obtained at wk 3, 5, 12, and 24 after calving was analyzed for IGF-1. Estrus was detected by use of milk progesterone profiles combined with visual observations (i.e., mounting behavior and other). The cows were divided into 2 groups: the cows having a negative LWG in each of the first 5 wk postpartum and the cows having a positive LWG in at least 1 of the first 5 wk after calving. The results indicate a similar decrease of 0.56 kg of milk per day of estrus during each of the 8 consecutive estruses. The activity level was 17 ± 1 movements per hour higher during the 8 estruses compared with the basic activity level. More cows expressed mounting behavior at estrus 8 than at estrus 2 (63.3 and 45.9%, respectively). The negative LWG cows had lower IGF-1 and higher milk production than the positive LWG cows. Both LWG groups had similar interval from calving to first estrus, on average 55 d. To conclude, the decrease in milk yield during estrus is marginal and similar in consecutive estruses. Moreover, estrous behavior is more highly expressed in the later estruses compared with the earlier estruses. Reproductive parameters (frequency of mounting, pregnancy risk, interval to first estrus, and between-estrus intervals) were not influenced by the live weight change during early lactation.

Good sensory quality and cheesemaking properties in milk from Holstein cows managed for an 18-month calving interval.

Extended calving interval (CInt) for high-yielding dairy cows beyond the traditional 12mo has been suggested as a profitable, environmentally and welfare-friendly production strategy. However, concerns exist on whether extending cow CInt, and consequently prolonging lactation length, impairs milk quality. The aim of this study was to compare the quality of milk produced during the extended lactation period to mid lactation. In particular, milk indicators related to udder integrity and cheesemaking properties when cows were fed low- or high-energy diets in early lactation mobilization period. Forty-seven healthy Danish Holstein cows (15 primi- and 32 multiparous) were fed 2 distinct weight-adjusted diets in early lactation: either a high-density diet for approximately 42d in milk (DIM) followed by a low-density diet (n=22), or a low-density diet throughout the whole experiment (n=25). Milk quality was explored at 3 lactation periods: 140 to 175 DIM (P1), 280 to 315 DIM (P2), and 385 to 420 DIM (P3). Lactation period was found to be the main factor affecting milk yield, quality, and cheesemaking properties. Primiparous cows kept the same daily milk yield throughout the studied periods, whereas multiparous cows produced, on average, 10.2kg/d less in P3 compared with P1. Fat, protein, and casein concentrations increased, respectively, by 18, 16, and 16%, from P1 to P3. Cheesemaking properties, such as curd-firming rate, gel strength, and wet and dry curd yield, got an improvement from P1 to P3 and were strongly correlated with milk concentrations of protein and casein. The udder integrity indicators, somatic cells count, level of free amino terminals as an index of proteolysis, and milk pH, remained unchanged throughout the studied lactation periods. Feeding cows either high- or low-density diets during the early lactation mobilization period did not exert any relevant carryover effect on milk composition, and thus had no effect on cheesemaking properties in extended lactation. Further, sensory quality of mid- and extended-lactation milk was assessed by a trained sensory panel. The sensory quality of milk from P3 reflected sensory descriptors related to the increased levels of fat and protein over lactation, but, importantly, milk produced in P3 did not present sensory demerits when compared with milk produced in P1. In conclusion, high-yielding Holstein cows undergoing an 18-mo CInt produced high-quality milk from mid to extended lactation.

Prediction of the lifetime productive and reproductive performance of Holstein cows managed for different lactation durations, using a model of lifetime nutrient partitioning.

The GARUNS model is a lifetime performance model taking into account the changing physiological priorities of an animal during its life and through repeated reproduction cycles. This dynamic and stochastic model has been previously used to predict the productive and reproductive performance of various genotypes of cows across feeding systems. In the present paper, we used this model to predict the lifetime productive and reproductive performance of Holstein cows for different lactation durations, with the aim of determining the lifetime scenario that optimizes cows' performance defined by lifetime efficiency (ratio of total milk energy yield to total energy intake) and pregnancy rate. To evaluate the model, data from a 16-mo extended lactation experiment on Holstein cows were used. Generally, the model could consistently fit body weight, milk yield, and milk components of these cows, whereas the reproductive performance was overestimated. Cows managed for repeated 12-, 14-, or 16-mo lactation all their life were simulated and had the highest lifetime efficiency compared with shorter (repeated 10-mo lactations: scenario N-N) or longer lactations (repeated 18-, 20-, or 22-mo lactations). The pregnancy rates increased slightly from a 10-mo to a 16-mo lactation but not significantly. Cows managed for a 16-mo lactation during their first lactation, followed by 10-mo lactations for the rest of their lives (EL-N scenario), had a similar lifetime efficiency as cows managed for 16-mo lactation all of their lives (EL-EL scenario). Cows managed for a 10-mo lactation during their first lactation, followed by 16-mo lactations for the rest of their lives (N-EL scenario), had a similar lifetime efficiency as that of the N-N scenario. The pregnancy rates of these 4 scenarios (N-N, EL-EL, N-EL, and EL-N) were similar to one another. To conclude, the GARUNS model was able to fit and simulate the extended lactation of Holstein cows. The simulated outputs indicate that managing the primiparous cows with a 16-mo extended lactation, followed by 10-mo lactations, allows their lifetime efficiency to increase and become similar to cows managed for 16-mo lactation during their entire lives. Further work should include health incidence (i.e., diseases) in the prediction model to have more accurate and realistic predictions of lifetime efficiency.

Effect of calving interval and parity on milk yield per feeding day in Danish commercial dairy herds.

The idea of managing cows for extended lactations rather than lactations of the traditional length of 1 yr primarily arose from observations of increasing problems with infertility and cows being dried off with high milk yields. However, it is vital for the success of extended lactation practices that cows are able to maintain milk yield per feeding day when the length of the calving interval (CInt) is increased. Milk yield per feeding day is defined as the cumulated lactation milk yield divided by the sum of days between 2 consecutive calvings. The main objective of this study was to investigate the milk production of cows managed for lactations of different lengths, and the primary aim was to investigate the relationship between CInt, parity, and milk yield. Five measurements of milk yield were used: energy-corrected milk (ECM) yield per feeding day, ECM yield per lactating day, cumulative ECM yield during the first 305 d of lactation, as well as ECM yield per day during early and late lactation. The analyses were based on a total of 1,379 completed lactations from cows calving between January 2007 and May 2013 in 4 Danish commercial dairy herds managed for extended lactation for several years. Herd-average CInt length ranged from 414 to 521 d. The herds had Holstein, Jersey, or crosses between Holstein, Jersey, and Red Danish cows with average milk yields ranging from 7,644 to 11,286 kg of ECM per cow per year. A significant effect of the CInt was noted on all 5 measurements of milk yield, and this effect interacted with parity for ECM per feeding day, ECM per lactating day and ECM per day during late lactation. The results showed that cows were at least able to produce equivalent ECM per feeding day with increasing CInt, and that first- and second-parity cows maintained ECM per lactating day. Cows with a CInt between 17 and 19 mo produced 476 kg of ECM more during the first 305 d compared with cows with a CInt of less than 13 mo. Furthermore, early-lactation ECM yield was greater for all cows and late-lactation ECM yield was less for second-parity and older cows when undergoing an extended compared with a shorter lactation. Increasing CInt increased the dry period length with 3 to 5d. In conclusion, the group of cows with longer CInt were able to produce at least equivalent amounts of ECM per feeding day when the CInt was up to 17 to 19 mo on these 4 commercial dairy farms.

Effects of an individual weight-adjusted feeding strategy in early lactation on milk production of Holstein cows during extended lactation.

Extending lactation by voluntarily delaying rebreeding aims to improve fertility and milk production in the modern dairy cow. Previous studies have shown that increased energy concentrations in the ration induced greater total milk yield and lactation persistency defined by the duration and the shape of the lactation curve. In this paper, we hypothesized that increasing the supply of energy during the early lactation mobilization period would have a positive carryover effect on milk production during extended lactation. A total of 53 Holstein cows completed a 16-mo lactation, including 30% primiparous cows. The cows were divided into 2 feeding strategies: half of the cows received a high-energy density diet (HD) in early lactation followed by a lower-energy density diet (LD; strategy HD-LD). The change in diet was defined individually after 42 d of lactation, and when the live weight (LW) gain of the cow was ≥ 0 based on a 5-d average. The other half of the cows were fed the LD diet during the entire lactation (strategy LD-LD). Both groups received 3 kg of concentrates per day during milking. Weekly milk composition (fat, protein, lactose, and somatic cells), daily milk production, daily feed intake, daily LW, and body condition score every second week were recorded. The fda package of R was used to model the curves of these different variables for the 53 cows that had a lactation over 400 d. The fitted values of these curves and the associated slopes were then compared for parity and treatment effects using a linear mixed-effects model. The HD-LD and LD-LD cows had a similar length of lactation (461 ± 7 d). The HD diet reduced the intensity of the mobilization period and increased the milk production of the multiparous cows in early lactation compared with the cows fed the LD diet. The primiparous cows used the extra energy to grow and gain weight, but not to produce more milk. After the shift in diet, the treatment had little short-term carryover effect on milk yield or LW, but it affected the slopes of some curves. From 0 to 50 d from shift, milk fat content of the LD-LD cows decreased faster than that of the HD-LD cows whereas milk lactose increased. From 250 to 350 d from shift, the energy-corrected milk decreased faster for the HD-LD cows than for the LD-LD cows. The lactose content in milk decreased faster for the LD-LD cows than for the HD-LD cows, and the fat content in milk was significantly higher for the primiparous HD-LD than for the primiparous LD-LD cows. In conclusion, the supply of extra energy during the mobilization period had a 300-d negative carryover effect on lactation persistency.

A tailored implementation strategy to reduce the duration of intravenous antibiotic treatment in community-acquired pneumonia: a controlled before-and-after study.

We previously showed that 40 % of clinically stable patients hospitalised for community-acquired pneumonia (CAP) are not switched to oral therapy in a timely fashion because of physicians' barriers. We aimed to decrease this proportion by implementing a novel protocol. In a multi-centre controlled before-and-after study, we evaluated the effect of an implementation strategy tailored to previously identified barriers to an early switch. In three Dutch hospitals, a protocol dictating a timely switch strategy was implemented using educational sessions, pocket reminders and active involvement of nursing staff. Primary outcomes were the proportion of patients switched timely and the duration of intravenous antibiotic therapy. Length of hospital stay (LOS), patient outcome, education effects 6 months after implementation and implementation costs were secondary outcomes. Statistical analysis was performed using mixed-effects models. Prior to implementation, 146 patients were included and, after implementation, 213 patients were included. The case mix was comparable. The implementation did not change the proportion of patients switched on time (66 %). The median duration of intravenous antibiotic administration decreased from 4 days [interquartile range (IQR) 2-5] to 3 days (IQR 2-4), a decrease of 21 % [95 % confidence interval (CI) 11 %; 30 %) in the multi-variable analysis. LOS and patient outcome were comparable before and after implementation. Forty-three percent (56/129) of physicians attended the educational sessions. After 6 months, 24 % (10/42) of the interviewed attendees remembered the protocol's main message. Cumulative implementation costs were 5,798 (20/reduced intravenous treatment day). An implementation strategy tailored to previously identified barriers reduced the duration of intravenous antibiotic administration in hospitalised CAP patients by 1 day, at minimal cost.