Association between serum mineral levels and reproductive performance in primiparous dairy cows during the peripartum period

Reprod Dom Anim. 2024;59:e14578.   | 1 of 9 https://doi.org/10.1111/rda.14578 wileyonlinelibrary.com/journal/rda Received:18December2023 | Accepted:11April2024 DOI: 10.1111/rda.14578 ORIGINAL ARTICLE Association between serum mineral levels and reproductive performance in primiparous dairy cows during the peripartum period Rodrigo Muiño1 | Cristina Castillo1 | Joaquín Hernandez1 | Marc Yeste2,3 | José L. Benedito1 This is an open access article under the terms of the CreativeCommonsAttribution-NonCommercial-NoDerivs License, which permits use and distribution in anymedium,providedtheoriginalworkisproperlycited,theuseisnon-commercialandnomodificationsoradaptationsaremade. ©2024TheAuthors.Reproduction in Domestic AnimalspublishedbyWiley-VCHGmbH. 1DepartmentofAnimalPathology, IBADER,FacultyofVeterinaryMedicine, Campus Terra, University of Santiago de Compostela, Lugo, Spain 2BiotechnologyofAnimalandHuman Reproduction (TechnoSperm), Institute ofFoodandAgriculturalTechnology, UniversityofGirona,Girona,Spain 3Unit of Cell Biology, Department of Biology,FacultyofSciences,Universityof Girona,Girona,Spain Correspondence JoaquínHernandez,Departmentof AnimalPathology,IBADER,Facultyof VeterinaryMedicine,CampusTerra, University of Santiago de Compostela, Lugo,ES-15705,Spain. Email:[email protected] Abstract To the best of the authors' knowledge, no study has previously investigated whether the concentration of minerals is related to reproductive outcomes in primiparous cows.Forthisreason,twoobjectivesweresetinthepresentstudy:(i)toassessserum mineral levels, macrominerals, and trace elements during the transition period (period of high nutritional requirements) in primiparous cows, considering reproductive efficiency, and (ii) to address if the serum mineral levels of primiparous cows are related to reproductive efficiency. Blood samples were taken (i) one month before calving, (ii) one week before calving, (iii) one week postpartum, and (iv) one month postpartum.Atthebeginningandtheendofthestudy,abodyconditionscore(BCS)wasassigned to each lactating cow with no clinical signs of disease. The difference between one month before and one month after calving was the body condition loss (ΔBCS). Optimal prepartum concentrations of K and Cl were associated with fewer days open andashorterintervalcalving.Furthermore,macromineralsintheserumdecreased immediately after calving (one week) but recovered at one month postpartum. In contrast, the highest concentration of trace elements was found at one week postpartum.PrimiparouscowswithhigherpostpartumSe,Mn,Co,andMoconcentrations exhibited better reproductive efficiency, and the concentrations of trace elements in serumwerecorrelatedwithintervalcalvingandthenumberofinseminations.Finally, primiparous cows with a greater ΔBCS (at least one point) in period 4 exhibited both a longer calving interval and a greater number of days open. In summary, this study showed, for the first time in primiparous cows, that the concentration of some serum minerals not only plays a crucial role during the transition period but is also related to crucial reproductive parameters, such as interval calving and days open. KEYWORDS cows,electrolyte,fertility,macro-andmicrominerals 2 of 9 | MUIÑO et al. 1 | INTRODUCTION During the transition period, marked physiological changes occur, such as foetal growth, preparation of the mammary gland for milk production, and postpartum uterine involution, which reset the reproductive cycle and enable the next pregnancy (Bell, 1995) and, specifically in the case of primiparous cows, complete their growth (Bach, 2011;Ettema&Santos,2004). These changes appear together with an increase in metabolic and hormonalactivityandnutrientrequirements(Lisuzzoetal.,2022), thus meeting all the demands for the subsequent dry period and early lactation(Grossetal.,2011).Providingadequateconcentrationofenergy, proteins, electrolytes, macrominerals, and trace elements in the diet of primiparous cows is essential to maintain the good health of the animals (Chan et al., 2005).Mineralsareessentialastheyplayafundamental role in the immune system, specifically in oxidative and energy metabolism (Rabiee et al., 2010).Formanyreasons,animbalanceinminerals isconnectedtoanincreaseintheprevalenceofseveraldiseases(Van Emonetal.,2020), with a decrease in both milk production (Bhanderi et al., 2016) and reproductive efficiency (Balmurugan et al., 2017). Currently, mineral imbalances are increasing in intensive farming systems(López-Alonso,2012;Palomares,2022) since the excess of some trace elements can be detrimental to the absorption of others (Xu et al., 2023; Zhao et al., 2023). It is, therefore, necessary to address the mineral needs (calcium, phosphorus, magnesium, sodium, potassium, chlorine, copper, zinc, iron, manganese, cobalt, molybdenum,andselenium)inHolsteinprimiparous cows to makeration adjustments and avoid economic losses (Van Emon et al., 2020). Deficiencies in major and minor minerals are known to be closely related to poor animal health, milk production, and reproductive efficiency (Constable et al., 2016). In animals supplemented, addressing this impact is particularly important during the transition between one month before calving and one month postpartum because this period is considered as a particularly stressful time for dairy cows. Animalsstarttomobilizefattomitigatethatimbalance,andasa result, they reduce their body condition score (BCS) in the transition period, which deteriorates their health status (Collard et al., 2000; Mulliganetal.,2006). Reduced BCS at calving is associated with lower milk yield and reduced likelihood of pregnancy (Chebel et al., 2018). In contrast, animals remaining in good condition during the first part oflactationexhibitshortercalvingintervals(Pryceetal.,2000). In addition, cows with a high BCS (higher than 3.75) upon parturition (the early postpartum period) have poor embryo development during the firstweekpost-inseminationinthenextcycle(Carvalhoetal.,2014). FollowingManríquezetal.(2021), animals that showed an optimal body condition score ΔBCS were less pronounced (between 0.5 and 0.6 points) than animals with considered high body condition, where the ΔBCS loss reached 1 point. Most research on the relevance of BCS for reproductive outcomes has analysed adult cows, with few contributions related to primiparouscows(Muiñoetal.,2021). The correlations of BCS with fatmobilization,milkproduction, and this interaction onlipidmetabolism have been studied. In recent years, a correlation of BCS genotypes and trace elements in dairy cattle serum has been documented (Denholm et al., 2022). Our hypothesis was to study if reproductive efficiency in primiparousdairycowscouldbeinfluencedbyserumminerallevels.Forthis purpose, concentrations of different minerals in serum were evaluated one month before calving, one week before calving, one week postpartum, and one month postpartum in primiparous cows. To understand whether minerals varied in a concerted manner over this transition period,aprincipalcomponentanalysis(PCA)wasundertaken.Inshort,this studyaimedto(i)evaluatetheserumminerallevelsofHolsteinprimiparous cows during the last third of pregnancy and the first month of lactation (ii) elucidate the possible interactions of serum mineral levels of primiparous cows is related to reproductive efficiency. 2 | MATERIALS AND METHODS 2.1 | Animals, housing, and diets All standards for animal handling and care were strictly followed, as indicated in the Spanish Regulations ((RD 53/2013), legal provisionnumber1337).ThisstudywasalsoauthorizedbytheBioethics Committee of the University of Santiago de Compostela, Spain, according to relevant Spanish Regulations. This trial was conducted on a commercial dairy herd located in Galicia, north-western Spain. In total, 25 healthy Holstein primiparouscows (body weight,mean ± standarddeviation [SD]: 620 ± 50 Kg)wereenrolledinthetrial.Heifersraisedonthesamefarmwere selectedbasedonthetimeofpregnancy.Noanimalswereexcluded fromthisstudy.ThesamplesizewascalculatedusingtheG*Power analysissoftware(Fauletal.,2017), taking into account the predesignedsizeofasmalldifferencebetweengroups,andCohen'sprinciples(Fauletal.,2017).Animalswerehousedinfreestallbarnsbedded with barley straw under the same feeding and handling conditions. Allanimalswerecorrectlyidentifiedwitha12-digiteartag,andthis identification was used to avoid errors in measurements and sampling during the study. The experimental period ran between one month before calving and up to one month after calving. Upon calving of the primiparous cow herd between 10 September and 30 December 2019, the cows weremovedtothefirst-calfcowherdandmilkedthreetimesperday. Thetemperaturehumidityindex(THI)wasrecordedintherange THI = 64–66duringstudy,withnoconsequencesonthehealthand welfareoftheanimals.AboveTHI70–72,theanimalisheatstressed. Animalswerefedatotalmixedration(TMR)formulatedaccording toNRC(2001)tomeetthelactationrequirements.Thedietafterparturition included corn silage (35 Kg fresh), grass silage (6 Kg fresh), and a specific concentrate composed of corn, rapeseed meal, soybean flour, barley, and beetroot molasses (12.6 Kg fresh), containing 171.5 g of crudeprotein(CP)/Kgofdrymatter(DM)and1.67Mcal/Kgofnetenergyforlactation(NEL).Thetotalmineralandvitamincontentofthediet was12 mg/KgofCu,18 mg/KgofFe,0.9 mg/KgofI,54 mg/KgofZn, 36 mg/KgofMn,0.180 mg/KgofCo,0.27 mg/KgofSe,7200 IUvitamin 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 3 of 9 MUIÑO et al. A/Kg,2250 IUvitaminD3/Kg,and30 IUvitaminE/Kg.Theanimaldiet before the parturition period consisted of a base ration fed as a daily TMRcontainingcornsilage(4Kgfresh),wheatstraw(6Kgfresh),and 5.2 Kg, fresh of a commercial concentrate composed of rapeseed meal, barley,andbeetrootmolasses,containing142.7 gofCP/KgofDMand 1.31Mcal/KgofNEL.Thetotalmineralandvitamincontentofthediet was28 mg/KgofCu,42 mg/KgofFe,2.1 mg/KgofI,126 mg/KgofZn, 84 mg/KgofMn,0.42 mg/KgofCo,0.63 mg/KgofSe,16.800 IUvitamin A/Kg,5250 IUvitaminD3/Kg,and70 IUvitaminE/Kg. The BCS was always recorded at the same time as venous collection by the same technician, an experienced veterinarian, using a scale wherethevalueof1correspondedtosevereunder-conditioningand 5correspondedtosevereover-conditioning(Fergusonetal.,1994). Furthermore,andaccordingtoManríquezetal.(2021), the variation of the BCS over the transition period was calculated (ΔBCS) within the same animal. The difference between one month before andonemonthaftercalvingwasthebodyconditionloss.Variationin BCS between one month before and one month after calving was also evaluated. Based on the numerical differences between time points, cows were assigned to one of the two categories: a large loss of BCS (more than 1 point; n = 10)orasmalllossofBCS(<1 point; n = 15) (Pinedoetal.,2022). 2.2 | Welfare assessment Allstandardsforanimalhandlingandcareforthisexperimentwere followed, as indicated in the Spanish Regulations ((RD 53/2013), legal provision number 1337). 2.3 | Determination of trace elements in serum VenousbloodsampleswerecollectedusingVacutainer® tubes without an anticoagulant, via jugular puncturing at one month (period 1) and one week before the expected calving (period 2), and one week andonemonthaftercalving(periods3and4,respectively).Allsamples (from 25 primiparous cows) were stored in a refrigerator (4°C) and processed at the Animal Pathology Laboratory, University of SantiagodeCompostela,inLugo,Spain,within24 hpost-collection. Samples were centrifuged at 3500× gfor10 mintoobtaintheserum, whichwasimmediatelyfrozeninanEppendorftubeat−20°Cuntil biochemical measurements were carried out. In total, 100 serum samples were analysed. Concentrations of macromineral calcium (mg/dL), phosphorus (mg/dL), and magnesium (mg/dL) in the serum were measured with a UV/Vis spectrophotometer (CST-240, DIRUI Industrial Co., Ltd, Changchun, China) calibrated against a multipoint calibrator (Biocal; RALTecnicaparaellaboratorioS.A.,Barcelona,Spain).Allthesedeterminations were performed using photometric commercial kits as follows:calcium(Arsenazo III; RAL TecnicaparaellaboratorioS.A.), magnesium(MagnesiumBlue;RALTecnicaparaellaboratorioS.A.),and phosphorus(DirectUV;RALTecnicaparaellaboratorioS.A.)(Abuelo et al., 2014).Ontheotherhand,serumconcentrationsofNa(mmol/L), Cl (mmol/L), and K (mmol/L) were determined withahand-heldportableanalyser(i-STATEC8+,EastWindsor.NJ,USA).Microelements athighconcentrations(copper(Cu)(ppm),iron(Fe)(ppm),manganese (Mn)(ppm),andzinc(Zn)(ppm))weredeterminedviaaninductively coupled plasma-optical emission spectrometer (ICP-OES; Perkin ElmerOptima4300DV,PerkinElmerInstruments,Norwalk,CTUSA) equippedwithaMicromistlow-flownebulizer,aPeltierquartzdouble- pass spray chamber, and a quartz torch. Microelements present at verylowconcentrations,suchascobalt(Co)(ppm),molybdenum(Mo) (ppm), and selenium (Se) (ppm), were determined via inductively coupledplasmamassspectrometry(ICP-MS;VGElementalPlasmaQuadS Option,ThermoScientific,Waltham,MA,USA). In all cases, samples were analysed in triplicate, and an analytical quality control was applied throughout the study. Reagent blanks were run alongside samples, and their values were subtracted from sample readings before the results were calculated. Limits of detection were set as three times the standard deviation of the reagent blanks. Limits of quantification, expressed as the concentration in the sample, were calculated based on the mean sample volume and the total volume analysed. Overall, seven samples (1.39%) fell below the quantification limitforoneormoreofthestudiedelements.Analyticalrecoveries weredeterminedfromaneatreferencesamplespikedin-house,with recoveries ranging between 83% and 118%. Collection tubes were tested for concentrations of trace elements by rinsing five tubes with 4 mLofglacialaceticacid(catalogue#A6283,Sigma-Aldrich,Munich, Germany)and analysing theleachingsolution (Abuelo etal.,2016), obtaining negligible contamination levels. 2.4 | Reproductive data Atransrectalultrasoundexaminationwascarriedout30 dayspostpartum to evaluate uterine involution was completed, and ovarian activitywaspresented.Noanimalinthestudywasdiseasedduring the peripartum period and only one animal was discarded due to calvingdifficulties.Theexaminationwasperformedusinga6.5 MHz rectal transducer (Easi Scan®, BCF Technology Ltd, Bellshill, UK). The voluntary waiting period ranged from 40 to 70 DIM (days in milk), and breeding management included combinations of timed artificialinseminations(AI)andheatdetection.Pregnancydiagnosis wascarriedout28–30 daysafterAIthroughtransrectalultrasonography.Non-pregnantanimalswereresynchronizedandinseminated at a fixed time, whereas the reproductive data of tested cows were transferredtoanAccess®(Microsoft;Redmond,USA)databaseto extract four reproductive parameters: days open, interval calving, the number of insemination, and number of calves. Days open is defined as the period between parturition and the conception of a dairy cow. Days open is a parameter used to determine reproductive performance and make an economic decision in dairy herds. In our study, the veterinarian established a period of 120 daysasthedaysopenbaseline(Harmanetal.,1996).Forstatistical purposes, animals were divided into two ranks: the first consisted 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 4 of 9 | MUIÑO et al. of primiparous cows with <120 daysopenn = 13,conceptionratewas 81%andthenumberofAIrangedbetween1and3,andthesecond wascomposedofanimalsmorethan120 daysopenn = 12,conceptionratewas29%andthenumberofAIrangedbetween4and6.The interval calving is defined as the time between the birth of one calf and the birth of the next calf from the same cow. The recommended optimalintervalis12 months(Burgersetal.,2022). Concerning days open, animals were also divided into two categories: The first consistedofprimiparouscowswithmorethan12 monthsofintervalcalving (n = 16),andthesecondcontainedcowswithanintervalcalving equalorshorterthan12 months(n = 9).Finally,thenumberofinsemination attempts needed to achieve pregnancy and the number of calvingwere established bya four-year follow-upamongthe same animals whose serum was sampled, and the number of calving was considered an indicator for the longevity of primiparous cows. 2.5 | Statistical analyses Data were analysed using a statistical package (IBM SPSS for Windows,Ver.27.0;Armonk,NY,USA).Datawerefirsttestedfor normal distribution and homogeneity of variances (Shapiro–Wilk andLevenetests).Formineralvalues,aprincipalcomponentanalysis(PCA)wasrunwiththedatafromallmeasurements.Principal component analysis is a multivariate technique that reduces the dimensionality of data by transforming a number of related variables into a set of uncorrelated variables, while retaining as much variation as possible. The new transformed variables, referred to as principal components(PCs),arelinearcombinationsoftheoriginalvariables. ThefirstPC(PC1)accountsforthemaximumvariability,whereasthe otherPCs(PC2,PC3,PCn,n = numberofvariables)describetheremainingvariabilityofthedata.AseachPCisindependentofandorthogonal to the others, and thus represents more than one mineral, these principal components were further used to determine the concerted variations of minerals during the transition period and to address whether they were related to reproductive performance. The resulting data matrix was rotated through the Varimax procedure andKaisernormalization,andtheregressionscoreswereusedfor further statistical analyses. Raw data from nutrients as well as the principalcomponentsresultingfromPCAweresubjectedtoamixed model (repeated measures) followed by a post-hoc Bonferroni's testforpair-wisecomparisons.Correlationswerecalculatedusing Spearman's rank coefficient. To test the relationship of ΔBCS and minerals status with reproductive efficiency, Spearman's rank correlation coefficient was calculated. In all statistical analyses, the level of significance was set at p ≤ .05. 3 | RESULTS 3.1 | Concentration of minerals in serum, and their relationship with days open and interval calving in primiparous cows The concentration of electrolytes, macrominerals, and trace elements were evaluated in the serum of Holstein primiparous cows from one month before calving to one month after calving (Tables 1 and 2); the possible interactions of these levels with reproductive parameters,werealsoinvestigated.Concentrationsofelectrolytes(Na, K, and Cl) in serum were found to decrease after calving in all animals (Table 1). These concentrations were significantly lower at one week(period3)andonemonthpost-calving(period4)thanatlate pregnancy (periods 1 and 2) (p < .001).Asignificantinteractionbetween K and interval calving was observed at one month postpartum (p < .05). Indeed, primiparous cows with K concentration in serum over3.75 ± 0.09 mmol/Lpresentedlowerintervalcalvingvaluesthan those with K concentration <3.43 + 0.09 mmol/L.Ontheotherhand, primiparous cows with the lowest Cl concentration in serum during the prepartum period and the highest concentration of this mineral during postpartum became pregnant earlier (<120 daysopen). Phosphoruswasthemoststablemacromineralduringtheperiod of study, as no significant differences between periods were observed.Valuesofmagnesiumandcalciuminserumfollowedasimilar pattern throughout the study, both reaching the minimum level at one TABLE 1 Meanvaluesofelectrolytes(Na,K,Cl)andminerals(Mg,P,Ca)atdifferentproductionstagesofprimiparousHolsteinFriesian dairycows(period1–4;4 weeksantepartum,1 weekprepartum,1 weekpostpartum,and4 weekspostpartum)andtheirinteractionwith reproductive parameters. Period 1 (n = 25) Period 2 (n = 25) Period 3 (n = 25) Period 4 (n = 25) TDO DOT CI CIT pvalue Na(mmol/L) 142.56 ± 0.40b143.76 ± 0.36b142.04 ± 0.26b139.84 ± 0.30a.000 .520 .418 .968 .983 K (mmol/L) 3.75 ± 0.07b3.91 ± 0.05b3.50 ± 0.04a3.54 ± 0.06a.000 .509 .568 .011 .03 Cl (mmol/L) 101.40 ± 0.44b103.40 ± 0.50b100.16 ± 0.40a98.7200 ± 0.50a.000 .066 .030 .105 .095 Mg(mg/dL) 2.04 ± 0.06c2.04 ± 0.03c1.93 ± 0.04a2.22 ± 0.02b.004 .764 .796 .321 .392 P(mg/dL) 7.02 ± 0.15 6.80 ± 0.09 9.23 ± 2.40 7.09 ± 0.09 .160 .776 .697 .811 .619 Ca (mg/dL) 9.04 ± 0.27c8.30 ± 0.36b7.31 ± 0.17a10.72 ± 0.26d.000 .381 .528 .771 .753 Note:Valueswithdifferentsuperscriptlettersandboldvaluesdenotediffersignificantly(p < .05). Abbreviations:CI,calvinginterval;CI-T,interactioncalvingintervalwithperiod;DO,daysopen;DO-T,interactiondaysopenwiththeperiod;T, period. 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 5 of 9 MUIÑO et al. week postpartum and the maximum level at one month postpartum (Table 1).Amongalltraceelementsobservedinthestudy(Mn,Fe,Co, Cu,Zn,Mb,andSe),MnandZndidnotshowdifferencesbetweenperiods.ConcentrationsofCu,Mb,Zn,andSeinserumwerethelowest at one week before calving (period 2), but they increased one month after calving (Table 2). Interestingly, only Se showed an interaction with interval calving; thus, primiparous cows recovering from calving (period4)withhighSeconcentration(124.29 + 3.73 ppm)exhibiteda shorter interval calving than those with a lower concentration of Se (108.81 + 2.79 ppm)atthesamesamplingpoint. 3.2 | Correlation between principal components and reproductive parameters The PCA of mineral concentration in 100 serum samples yielded three principal components, as indicated in Table 3. The first component(PC1)containedNa,K,andCl;thesecondcomponent(PC2) included calcium,magnesium,and Fe. Thethird component (PC3) containedMn,Co,andMo.Thesethreeprincipalcomponentscould explainupto52.56%ofthetotalvariance,asfollows:22.61%(PC1), 17.71%(PC2),and12.24%(PC3). Table 4 shows the correlation coefficients between the principal components and different reproductive parameters. There was a positive correlation between PC1 (which contained Na, K, and Cl) and number of calving one month before pregnancy (S1) in primiparous cows (r = .425, p < .05), whereas nutritional requirements were the greatest at one month post-calving, in agreement with the results ofMulliganetal.(2006).Inthisperiod,thehighestvariationinPC1 (Na,K,andCl)wasobserved.PC2,whichincludedFeandminerals, was found to be negatively correlated with interval calving (r = −.523, p < .01)anddaysopen(r = −.537,p < .01). In general, the BCSs of primiparous cows decreased from the dry period until the first month of lactation, no significant correlations were identified between minerals and the ΔBCS.Asignificantnegative correlation between days open and ΔBCS (at least one point) was identified (r = −.344,p < .05). 4 | DISCUSSION The 13 minerals analysed in this study were observed to vary according to physiological status, decreasing in the postpartum week and then recovering again, although without reaching the initial values(onemonthprepartum)atonemonthpost-calving.Byknowing these values and their variations, diets can be supplemented with the required amounts of these minerals, if biologically necessary. Thefirstcomponent,PC1(whichincludedNa,K,andCl),specifically, the optimal electrolyte status of K and Cl at prepartum, was associated with fewer days open (r = −.537, p < .01) and a shorter calving interval (r = −.523,p < .01). Primiparouscowsthatarrivedto calving with higher concentrations of these two electrolytes adapted better to their morphological and functional changes and exhibited improved reproductive efficiency (Skrzypczak et al., 2015). These TABLE 2 Meanvaluesoftraceminerals(Mn,Fe,Co,Cu,Zn,Mo,Se)atdifferentproductionstagesofprimiparousHolsteinFriesian dairycows(period1–4;4 weeksantepartum,1 weekprepartum,1 weekpostpartumand4 weekspostpartum)andtheirinteractionwith reproductive parameters. Period 1 (n = 25) Period 2 (n = 25) Period 3 (n = 25) Period 4 (n = 25) TDO DOT CI CIT p value Mn(ppm) 1.27 ± 0.11b1.31 ± 0.12 1.41 ± 0.13 1.56 ± 0.10 .226 .093 .080 .073 .062 Fe(ppm) 2197.54 ± 130.53b1807.21 ± 95.14a1624.53 ± 98.26a1613.68 ± 54.59a.014 .300 .349 .952 .958 Co (ppm) 0.40 ± 0.03b0.41 ± 0.01c0.31 ± 0.01b0.27 ± 0.00a.000 .862 .934 .637 .493 Cu (ppm) 538.48 ± 15.22a558.67 ± 17.80a794.89 ± 27.02b736.34 ± 25.04b.000 .0032 .165 .508 .536 Zn (ppm) 794.63 ± 27.04b731.43 ± 24.52a775.77 ± 20.91b818.80 ± 21.75c.208 .936 .870 .634 .816 Mo(ppm) 6.77 ± 2.59b4.43 ± 0.46a9.45 ± 0.72c8.40 ± 0.78c.000 .239 .659 .109 .110 Se (ppm) 93.30 ± 2.58b87.39 ± 2.95b94.46 ± 1.65b114.38 ± 2.66c.000 .671 .671 .022 .021 Note:Valueswithdifferentsuperscriptlettersandboldvaluesdenotediffersignificantly(p < .05). Abbreviations:CI,calvinginterval;CI-T,interactioncalvingintervalwithperiod;DO,daysopen;DO-T,interactiondaysopenwithperiod;T,period. TABLE 3 Principalcomponent(PC1–3)loadingsinthefirstthree eigenvectorsfor13minerals(Na,K,Cl,Mg,P,Ca,Mn,Fe,Co,Cu, Zn,Mo,Se)weredeterminedin100serumsamples. Element PC 1 PC 2 PC 3 Na(mmol/L) 0.813 −0.189 −0.039 K (mmol/L) 0.474 −0.033 0.011 Cl (mmol/L) 0.785 0.039 −0.095 Mg(mg/dL) −0.010 0.836 −0.033 P(mg/dL) 0.038 −0.099 0.002 Ca(mg/dL) −0.169 0.737 0.111 Mn(ppm) −0.145 0.257 0.687 Fe(ppm) 0.372 0.562 −0.062 Co (ppm) 0.506 0.048 0.681 Cu (ppm) −0.611 −0.147 0.055 Zn (ppm) −0.027 0.513 −0.151 Mo(ppm) −0.190 −0.355 0.730 Se (ppm) −0.511 0.618 0.071 Note: Bold values denote significant elements. 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 6 of 9 | MUIÑO et al. two electrolytes were observed to fluctuate from high values at one month prepartum to low concentration at the first week postpartum, with a further recovery, which agrees with the results of other authors(Kupczyńsk&Chudoba-Drozdowska,2002).Afzaaletal.(2004) noted that the decrease in K concentration after calving could be connected with the activity of the mammary gland, which requires energy intheformofATPtoachievethesynthesisoflactose.Furthermore, Skrzypczaketal.(2015)noted that a decreaseinNaconcentration during the first weeks of lactation, which was also observed in the current study, could be a consequence of decreased plasma rennin activityinmultiparouscowsaftercalving.Asthemainextracellularcation responsible for the osmotic force that maintains the extracellular fluid compartment,changesinNacouldbeattributabletoanincreasein milk production, which suggests free water movement into the udder (Muiñoetal.,2021).Indeed,althoughNaconcentrationintheserum was not observed to be correlated with reproductive performance in the current study, the results obtained in this work agree with those obtainedbyHernándezetal.(2022) and could be related to the increase in milk production caused by the lactose synthesized in the udder, which suggests free water movement to this organ. Thesecondcomponent(PC2)includedmacrominerals(Ca,Mg,Fe) involved in many biological processes, either as structural elements or asregulatorsofmetabolicpathways(Bauman&Currie,1980). These mineralsalsoplayaroleintheacid–basestatusofthemultiparous dairy cow and affect calcium metabolism (Wilde, 2006). Calcium is the most ubiquitous mineral in cows. While the calcium requirement per dayformaintenancepurposesisapproximately15.4 mgCa/Kgofbody mass(Hansardetal.,1954), the concentration needed for lactation increasesupto1.23 gCa/Kgofmilkproduced.Magnesiumisabsorbed in the rumen, and its metabolism is connected to other trace minerals. In this study, calcium and magnesium exhibited similar variations, with minimum values observed at one week postpartum and maximum values found at one month postpartum (Silva et al., 2023). In addition, a positive and statistically significant correlation between magnesium and calcium concentration was identified at four weeks postpartum in primiparous cows; animals with high concentrations of magnesium and calcium showed a reduced calving interval. Furthermore, high magnesium concentrations in serum during the transition period were notablyassociatedwithlowerincidenceratesofperi-andpostpartum disorders (dystocia, retained placenta, endometritis, and lameness) and improved reproductive performance in multiparous dairy cows (Jeong et al., 2018).Furthermore,Wilde(2006) and Wynn et al. (2015) noted that preventing problems during the peri-parturition period, such as hypocalcaemia or retention of the placenta, could avoid harming the cow's future fertility. Information published on the relationship between calcium concentration in serum and fertility, however, remains scarce and inconsistent. Risco et al. (1994) and (Whiteford &Sheldon,2005) suggested that the inferior fertility parameters observed in multiparous cows with lower calcium concentrations in their serum could be due to an indirect effect on the processes connected with a return to ovarian cyclicity, the expression of oestrus, and the ability to conceive and maintain a pregnancy, rather than a direct effect on fertility itself considering the association of the BCS on minerals,primiparouscowswithanoptimalbodycondition(3.25–3.5)were found to have higher concentration of calcium and magnesium in the last week before calving, in agreement with the results published in previousstudies(Hadžimusić&Krnić,2012).Feisanessentialmicronutrient for all animal species, with forage representing the primary source of iron in cows. This element participates in several biochemical processes including blood production, the transport of oxygen, energy metabolism, and immune processes (Wysocka et al., 2020). TheresultsofthisstudyshowedthatFeconcentrationwaslowestin animals one week before calving, and highest at one month after calving.FeandothermineralsincludedinPC2,onemonthpost-calving were found to be negatively correlated with calving interval (r = −.523, p < .01)anddaysopen(r = −.537,p < .01). Furthermore, phosphorus is indispensable for the growth and metabolismofrumenmicroorganisms(Nkrumahetal.,2006). In the presentwork,amongthethreemacrominerals(Ca,Mg,P),theconcentration of phosphorus was found to be the most stable throughout the period of study, with no significant differences between measurements. ForPC3(Mn,Co,Mo),apositivecorrelationwasestablishedbetween the group of primiparous cows with a higher concentration of TABLE 4 Correlationbetweentheprincipalcomponents(PC)duringthefourperiods(P1,P2,P3,P4)ofthemineralsstudied. DO NIA IC NC PC 1 P1 PC 2 P1 PC 3 P1 PC 1 P2 PC 2 P2 PC 3 P2 DO 1−0.848** 0.811** 0.059 0.307 0.197 −0.092 0.143 0.169 0.088 NIA −0.848** 1−0.716** −0.021 −0.194 −0.209 0.155 0.064 −0.069 −0.176 CI 0.811** −0.716** 1−0.188 −0.050 0.117 −0.212 0.156 0.173 0.016 NC 0.059 −0.021 −0.188 10.425*0.206 −0.016 0.007 0.059 0.111 PC 1 P3 PC 2 P3 PC 3 P3 PC 1 P4 PC 2 P4 PC 3 P4 DO 0.072 0.263 −0.327 −0.537** −0.222 −0.198 NIA 0.107 −0.123 0.451*0.145 0.073 0.312 CI 0.133 0.149 −0.368 −0.523** −0.486*−0.245 NC −0.127 0.378 0.175 0.131 0.362 −0.016 Abbreviations:CI,calvinginterval;DO,daysopen;NC,numbercalving;NIA,numberofinsemination;PC1–3,principalcomponent1–3. *Valueswithdifferentsuperscriptsandinboldsignsdiffersignificantly(p < .05).**Valueswithdifferentsuperscriptsandinboldsignsdiffer significantly (p < .001). 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 7 of 9 MUIÑO et al. trace elements at one week postpartum (S3) and the number of inseminations (r = .451,p < .05)(Table 4). In agreement with these findings, VanEmonet al.(2020) suggested that these high postpartum mineral concentrations in serum could indicate faster uterine involution followingparturition.SupplementationwithZn,Mn,Cu,andCowas previously related to pregnancy rates above 20% for animals without supplementation but with different results between the various years studied(Aholaetal.,2004).Maternalmineralstatus,however,clearly affects the health of the mother's oocytes, as well as the embryonic andfoetaldevelopmentofthefutureheifer(VanEmonetal.,2020). Two different patterns in the concentration of trace elements wereidentifiedduringthesamplingperiod.Ontheonehand,Mnand Zn remained stable during the period of study (Table 2) without significantdifferencesbetweensamples.Incontrast,Cu,Mo,Zn,andSe reached their minimum concentration in primiparous cows one week before calving, and higher concentration one month after calving. Selenium was the only trace element for which we could establish an association between the concentration at one month postpartum and a reduced interval calving (Table 2). These data agree with those of previous studies, in which low Se concentrations were associated with a decrease in reproductive efficiency in multiparous cows (Spears &Weiss,2008). Such a decrease could be related to a reduced concentration of progesterone (Kamal et al., 2020), a decrease in conception rate (Khalili et al., 2019), and an increase in the days open period (Khatti et al., 2017). These data also suggest that the reproductive decline and increased dysfunction resulting from Se deficiency in multiparous dairy cows represent a significant problem. Se was suggested to act as an antioxidant at the ovarian level protecting the oocyte from oxidativestressandDNAdamageduringfolliculogenesis(Hernández et al., 2022).AnotherpossiblemechanismofactionofSeinbovinereproduction was described by Basini and Tamanini (2000), who demonstrated that both granulosa cell proliferation and oestradiol synthesis areaffectedbySeinvitro.Notably,controllingthephysiologicalconcentrationsoflutealROSviaantioxidantenzymesisakeyfactorinthe corpus luteum's production of progesterone, whereas uncontrolled ROS generation caused by an imbalance between ROS and the antioxidant systems is detrimental to the corpus luteum at the end of the non-fertilereproductivecycle(Al-Guborietal.,2012). Concerning BCS changes associated with physiological status, primiparous cows were observed to lose BCS throughout the experiment due to their lower dry matter intake and higher lactation requirements(Grossetal.,2011).Previousstudiesinmultiparouscows established that a higher magnitude of BCS changes (ΔBCS) after the dry period and during the transition period is a key factor affecting fertility, health, and subsequent survival (Carvalho et al., 2014; Chebel et al., 2018).TheresultsofthisstudyareinagreementwithFricke et al. (2023), who found an association between lower ΔBCS and a reduction in days open. This work has several strengths and limitations. The main contribution of this study is its evaluation of reproductive parameters based on mineral concentration in serum affect these variables using a principal component analysis. These parameters were measured along four different periods: one month before calving, one week before calving,oneweekpostpartum,andonemonthpostpartum.Yet,this study was conducted under field conditions, and this experimental environmentcouldbeperceivedasalimitationbecausethesamplesize relied upon that of the farm, and the results could have been affected by the farm's operations. 5 | CONCLUSION Based on the results obtained, macrominerals were found to decrease after calving, whereas trace elements increased during this period. An adequate concentrationof serummicrominerals,especially Mn,Co,Se, and Mo, was foundto be crucialfor thereproductive success. Finally, primiparous cows with a greater ΔBCS exhibited a higher number of days open. AUTHOR CONTRIBUTIONS Conceptualization,RodrigoMuiño,JoaquínHernandez,MarcYeste, andCristinaCastillo;methodology,RodrigoMuiño,JoséL.Benedito, andMarcYeste,formalanalysis,RodrigoMuiño,JoaquínHernandez, Marc Yeste, and Cristina Castillo; investigation, José L. Benedito, MarcYesteandCristinaCastillo;writing–originaldraftpreparation, RodrigoMuiño,JoaquínHernandez,andCristinaCastillowriting– reviewandeditingRodrigoMuiño,JoaquínHernandez,andCristina Castillo.Allauthorshavereadandagreedtothepublishedversion of the manuscript. CONFLICT OF INTEREST STATEMENT Noneoftheauthorshaveanyconflictofinteresttodeclare. DATA AVAILABILITY STATEMENT The data that support the findings of this study are available from the corresponding author upon reasonable request. ORCID Rodrigo Muiño https://orcid.org/0000-0002-9518-808X Cristina Castillo https://orcid.org/0000-0002-2467-6406 Joaquín Hernandez https://orcid.org/0000-0002-2588-0089 Marc Yeste https://orcid.org/0000-0002-2209-340X José L. Benedito https://orcid.org/0000-0003-0862-1672 REFERENCES Abuelo,A., Hernández,J.,Alves-Nores,V., Benedito,J.L., & Castillo,C. (2016). Association of serum concentration of different trace elements with biomarkers of systemic oxidant status in dairy cattle. Biological Trace Element Research, 174,319–324.https:// doi. org/ 10. 1007/s12011-016-0713-4 Abuelo,A.,Hernández,J.,Benedito,J.L.,&Castillo,C.(2014).Comparative study of the metabolic profile, insulin sensitivity and inflammatory response between organically and conventionally managed dairy cattle during the periparturient period. Animal, 8,1516–1525.https:// doi. org/ 10. 1017/ S1751 73111 4001311 Afzaal,D.,Nisa,M.,Khan,M.A.,&Sarwar,M.A.(2004).Reviewonacid basestatusindairycows:Implicationsofdietarycation-anionbalance. Pakistan Veterinary Journal, 24,199–202. 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 8 of 9 | MUIÑO et al. Ahola,J.K.,Baker,D.S.,Burns,P.D.,Mortimer,R.G.,Enns,R.M.,Whittier, J.C.,Geary,T.W.,&Engle,T.E.(2004).Effectofcopper,zinc,and manganese supplementation and source on reproduction, mineral status,andperformanceingrazingbeefcattleoveratwo-yearperiod. Journal of Animal Science, 82,2375–2383.https:// doi. org/ 10. 2527/ 2004. 8282375x Al-Gubori,K.H.,Garrel,C.,Faure,P.,&Sugino,N.(2012).Rolesofantioxidant enzymes in corpus luteum rescue from reactive oxygen species-induced oxidative stress. Reproductive BioMedicine Online, 25,551–560.https:// doi. org/ 10. 1016/j. rbmo. 2012. 08. 004 Bach, A. (2011). Associations between several aspects of heifer development and dairy cow survivability to the second lactation. Journal of Dairy Science, 94, 1052–1057. https:// doi. org/ 10. 3168/ jds. 2010-3633 Balmurugan, B., Ramamoorthy, M., Mandal, K., Keerthana, J., Gopalakrishnan,G.,Kavya,K.M.,Kharayat,N.S.,Chaudhary,G.R., & Katiyar, R. (2017). Mineral and important nutrient for efficient reproductive health in dairy cattle. International Journal of Science, Environment and Technology, 6,694–701. Basini, G., & Tamanini, C. (2000). Selenium stimulates estradiol productioninbovinegranulosacells:Possibleinvolvementofnitricoxide. Domestic Animal Endocrinology, 18, 1–17. https:// doi. org/ 10. 1016/ s0739-7240(99)00059-4 Bauman,D.E.,&Currie,W.B.(1980).Partitioningofnutrientsduringpregnancyandlactation:Areviewofmechanismsinvolvinghomeostasis and homeorhesis. Journal of Dairy Science, 63,1514–1529.https:// doi.org/10.3168/jds.S0022-0302(80)83111-0 Bell,A.W.(1995).Regulationoforganicnutrientmetabolismduringtransition from late pregnancy to early lactation. Journal of Animal Science, 73,2804–2819.https:// doi. org/ 10. 2527/ 1995. 7392804X Bhanderi,B.M.,Goswami,A.,Garg,M.R.,&Samanta,S.(2016).Studyon minerals status of dairy cows and their supplementation through area specific mineral mixture in the state of Jharkhand. Journal of Animal Science and Technology, 58, 42. https:// doi. org/ 10. 1186/ s4078 1-016-0124-2 Burgers,E.E.A.,Kok,A.,Goselink,R.M.A.,Hogeveen,H.,Kemp,B.,& VanKnegsel,A.T.M.(2022).Revenuesandcostsofdairycowswith differentvoluntarywaitingperiodsbasedondataofarandomized control trial. Journal of Dairy Science, 105,4171–4188.https:// doi. org/10.3168/jds.2021-20707 Carvalho,P.D.,Souza,A.H.,Amundson,M.C.,Hackbart,K.S.,Fuenzalida, M.J.,Herlihy,M.M.,Ayres,H.,Dresch,A.R.,Vieira,L.M.,Guenther, J.N., Grummer, R. R., Fricke, P. M.,Shaver,R.D., & Wiltbank, M. C. (2014). Relationships between fertility and postpartum changes in body condition and body weight in lactating dairy cows. Journal of Dairy Science, 97, 3666–3683. https:// doi. org/ 10. 3168/ jds. 2013-7809 Chan,P.S.,West,J.W.,Bernard,J.K.,&Fernandez,J.M.(2005).Effects of dietary cation-anion difference on intake, milk yield, and blood components of the early lactation cow. Journal of Dairy Science, 88, 4384–4392.https://doi.org/10.3168/jds.S0022-0302(05)73125-8 Chebel, R. C., Mendonça, L. G. D., & Baruselli, P. S. (2018). Association between body condition score change during the dry period and postpartum health and performance. Journal of Dairy Science, 101, 4595–4614.https://doi.org/10.3168/jds.2017-13732 Collard,B.L.,Boettcher,P.J.,Dekkers,J.C.M.,Petitclerc,D.,&Schaeffer, L. R. (2000). Relationship between energy balance and health traits of dairy cattle in early lactation. Journal of Dairy Science, 83,2683–2690. https://doi.org/10.3168/jds.S0022-0302(00)75162-9 Constable, P. D., Hinchcliff, K., Done, S. H., & Grünberg, W. (2016). Veterinary medicine: A textbook of diseases cattle, horses, sheep, pigs, and goats(11thed.).SaundersElsevier. Denholm, S. J., McNeilly, T. N., Bashir, S., Mitchell, M. C., Wall, E., & Sneddon,A.A.(2022).Correlationsofmilkandserumelementconcentrations with production and management traits in dairy cows. Journal of Dairy Science, 105,9726–9737. Ettema,J.F.,&Santos,J.E.P.(2004).Impactofageatcalvingonlactation, reproductionhealth,andincomeinfirst-parityHolsteinoncommercial farms. Journal of Dairy Science, 87,2730–2742.https:// doi. org/ 10.3168/jds.S0022-0302(04)73400-1 Faul, F., Erdfelder, E., Lang, A. G., & Buchner, A. (2017). G*power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods, 39,175–191. https://doi.org/10.3758/BF03193146 Ferguson,J.D.,Galligan,D.T.,&Thornsen,N.(1994).Principaldescriptors ofbodyconditionscoreinHolsteincows.Journal of Dairy Science, 77, 2695–2703. Fricke, P. M., Wiltbank, M. C., & Pursley, J. R. (2023). The high fertility cycle. JDS Communications, 4, 127–131. https:// doi. org/ 10. 3168/ jdsc.2022-0280 Gross,J.,vanDorland,H.A.,Bruckmaier,R.M.,&Schwarz,F.J.(2011). Performance and metabolic of dairy cows during a lactational and deliberately induced negative energy balance with subsequent realimentation. Journal of Dairy Science, 94,1820–1830.https:// doi. org/ 10.3168/jds.2010-3707 Hadžimusić,N.,&Krnić,J.(2012).Valuesofcalcium,phosphorusandmagnesium concentrations in blood plasma of cows in dependence on the reproductive cycle and season. Acta Veterinaria Eurasia, 38,1–8. https:// doi. org/ 10. 16988/ iuvfd. 44551 Hansard,S. L., Comar, C. L., & Davis,G.K.(1954). Effects of age upon the physiological behavior of calcium in cattle. American Journal of Physiology, 177,383–389.https:// doi. org/ 10. 1152/ ajple gacy. 1954. 177.3. 383 Harman,J.L.,Casella,G.,&Gröhn,Y.T.(1996).Theapplicationofevent- time regression techniques to the study of dairy cow interval-to- conception. Preventive Veterinary Medicine, 26,263–274.https:// doi. org/10.1016/0167-5877(95)00553-6 Hernández,J.,Muiño,R.,Benedito,J.L.,Abuelo,A.,&Castillo,C.(2022). Redox status and oxidative stress in bovine. Large Animal Review, 28, 145–151. Jeong, J. K., Choi, I. S., Moon, S. H., Kang, H. G., & Kim, I. H. (2018). Relationship between serum magnesium concentration during the transitionperiod,peri-andpostpartumdisorders,andreproductive performance in dairy cows. Livestock Science, 213,1–6.https:// doi. org/ 10. 1016/j. livsci. 2018. 04. 013 Kamal,F.,Ullah,H.,Khan,H.,Knoca,H.,&Khan,R.U.(2020).Effectsoforganic selenium on blood progesterone, metabolires, milk yield and service period of Jersey cows. Journal of Animal Physiology and Nutrition Science, 1,7–11.https://doi.org/10.46417/JAPN/2020.002 Khalili,M.,Chamani,M.,Amanlou,H.,Nikkhah,A.,Sadeghi,A.A.,Dehkordi, F.K.,Rafiei,M.,&Shirani,V.(2019).Theeffectoffeedinginorganic and organic selenium sources on the hematological blood parameters, reproduction and health of dairy cows in the transition period. Acta Scientiarum Animal Science, 42,1–10.https:// doi. org/ 10. 4025/ actas ciani msci. v42i1. 4537. 1 Khatti, A., Mehrotra, S., Patel, P. K., Singh, G., Maurya, V. P., Mahla, A. S., Chaudhari, R. K., Das, G. K., Shingh, M., Sarkar, M., Kumar, H., &Krishnaswamy,N.(2017).SupplementationofvitaminE,selenium and increase energy allowance mitigates the transition stress and improves postpartum reproductive performance in the crossbred cow. Theriogenology, 104,142–148.https:// doi. org/ 10. 1016/j. theri ogeno logy. 2017. 08. 014 Kupczyńsk, R., & Chudoba-Drozdowska, B. (2002). Values of selected biochemicalparameters ofcows'blood duringtheirdrying-offand the beginning of lactation. Electronic Journal of Polish Agricultural Universities, 5(1), 01. Availabe online https://www.ejpau.media.pl/ volume5/issue1/veterinary/art01.html Lisuzzo, A., Laghi, L., Fiore, F., Harvatine, K., Mazzotta, E., Faillace, V., Spissu,N.,Zhu,C.,Moscati,L.,&Fiore,E.(2022).Evaluationofthe metabolomic profile through (1)H-NMR spectroscopy in ewes affected by postpartum hyperketonemia. Scientific Reports, 12, 16463. https://doi.org/10.1038/s41598-022-20371-9 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 9 of 9 MUIÑO et al. López-Alonso,M.(2012).Tracemineralsandlivestock:Nottoomuchnot too little. ISRN Veterinary Science, 4,1–18.https:// doi. org/ 10. 5402/ 2012/ 704825 Manríquez,D.,Thatcher,W.W.,Santos,J.E.P.,Chebel,R.C.,Galvão,K. N.,Schuenemann,G.M.,Bicalho,R.C.,Gilbert,R.O.,Rodriguez-Zas, S.,Seabury,C.M.,Rosa,G.J.M.,&Pinedo,P.(2021).Effectofbody condition change and health status during early lactation on performanceandsurvivalofHolsteincows.Journal of Dairy Science, 104, 12785–12799. Muiño,R.,Hernández,J.,Benedito,J.L.,&Castillo,C.(2021).Effectsof calvingbodyconditionscoreonbloodacid-basebalanceofprimiparousHolsteinFriesiandairycowsinacommercialdairyfarm:Acase study. Animals, 11, 2075. https:// doi. org/ 10. 3390/ ani11 072075 Mulligan,F.,O'Grady,L.,Rice,D.,&Doherty,M.(2006).Productiondiseases of the transition cow: Body condition score and energy balance. Irish Veterinary Journal, 59,505–510.https:// doi. org/ 10. 3390/ ani11 072075 Nkrumah,J.,Okine,E.,Mathison,G.,Schmid,K.,Li,C.,Basarab,J.A.,Price, M.A.,Wang,Z.,&Moore,S.S.(2006).Relationshipsoffeedlotfeed efficiency, performance, and feeding behavior with metabolic rate, methane production, and energy partitioning in beef cattle. Journal of Animal Science, 84, 145–153. https:// doi. org/ 10. 2527/ 2006. 841145x Palomares,R.A.(2022).Tracemineralssupplementationwithgreatimpact on beef cattle immunity and health. Animals, 12, 2839. https:// doi. org/ 10. 3390/ ani12 202839 Pinedo,P.,Manríquez,D., Azocar, J., Klug, B. R., & De Vries, A.(2022). Dynamics of automatically generated body condition scores during early lactation and pregnancy at first artificial insemination of Holsteincows.Journal of Dairy Science, 105,4547–4564.https:// doi. org/10.3168/jds.2021-21501 Pryce, J. E., Coffey, M. P., & Brotherstone, S. (2000). The genetic relationship between calving interval, body condition score and linear type and management traits in registered Holsteins. Journal of Dairy Science, 83, 2664–2671. https:// doi. org/ 10. 3168/ jds. s0022 -0302(00)75160-5 Rabiee,A.R.,Lean,I.J.,Stevenson,M.A.,&Socha,M.T.(2010).Effects of feeding organic trace mineral on milk production and reproductive performanceinlactatingdairycows:Ameta-analysis.Journal of Dairy Science, 93,4239–4251.https://doi.org/10.3168/jds.2010-3058 Real Decreto 53/2013, de 1 de Febrero, por el que se Establecen las Normas Básicas Aplicables Para la Protección de los Animales utilizados en Experimentación y otros Fines Científicos, Incluyendo laDocencia.BoletinOficialdelEstadodelGobiernodeEspaña34. Retrieved June 20, 2023, from https:// www. boe. es/ buscar/ doc. php? id=BOE-A-2021-2845 Risco, C. A., Drost, M., Thatcher, W. W., Sabio, J., & Thatcher, M. J. (1994). Effects of calving-related disorders on prostaglandin, calcium, ovarian activity and uterine involution in postpartum dairy cows. Theriogenology, 42,183–203.https://doi.org/10.1016/0093- 691x(94)90675-9 Silva,J.H.,Contreras,L.V.Q.,Ponath,C.F.,Bondan,C.,Machado,M.C., &González,F.(2023).Bloodconcentrationsofcalcium,phosphorus and magnesium and dietary cation-anion difference in dairy cows. Arquivo Brasileiro de MedicinaVeterinaria e Zootecnia, 75,127–136. https://doi.org/10.1590/1678-4162-12774 Skrzypczak,W.,Kurpińska,A.,Stański,L.,&Jarosz,A.(2015).Sodium,potassium and chloride homeostasis in cows during pregnancy and first months of lactation. Acta biológica Cracoviensia, 55,58–64. Spears,J.W.,&Weiss,W.P.(2008).Roleofantioxidantsandtraceelements in health and immunity of transition dairy cows. The Veterinary Journal, 176(1),70–76.https:// doi. org/ 10. 1016/j. tvjl. 2007. 12. 015 VanEmon,M.,Sanford,C.,&McCoski,S.(2020).Impactsofbovinetrace mineral supplementation on maternal and offspring production and health. Animals, 10(12), 2404. https:// doi. org/ 10. 3390/ ani10 122404 Whiteford,L.C.,&Sheldon,I.M.(2005).Associationbetweenclinicalhypocalcaemia and postpartum endometritis. Veterinary Record, 157, 202–203.https:// doi. org/ 10. 1136/ vr. 157.7. 202 Wilde, D. (2006). Influence of macro and micro minerals in the periparturient period on fertility in dairy cattle. Animal Reproduction Science, 96, 240–249.https:// doi. org/ 10. 1016/j. anire prosci. 2006. 08. 004 Wynn,S.,Teramura,M.,Sato,T.,&Hanada,M.(2015).Changesofserum calcium concentration, frequency of ruminal contraction and feed intake soon after parturition of dairy cows fed difructose anhydride III. AsianAustralasian Journal of Animal Sciences, 28,58–68.https:// doi. org/ 10. 5713/ ajas. 14. 0418 Wysocka,D.,Snarska,A.,&Sobiech,P.(2020).Ironincattlehealth.Journal of Elementology, 25, 1175–1185. https:// doi. org/ 10. 5601/ jelem. 2020. 25.2. 1960 Xu,Z.J.,Liu, M., Niu, Q. J., Huang, Y. X., Zhao, L., Lei, X.G., & Sun,L. H.(2023).Bothseleniumdeficiencyandexcessimpairmalereproductive system via inducing oxidative stress-activated PI3K/AKT- mediated apoptosis and cell proliferation signaling in testis of mice. Free Radical Biology and Medicine, 197, 15–22. https:// doi. org/ 10. 1016/j. freer adbio med. 2023. 01. 024 Zhao,L.,Liu,M.,Sun,H.,Yang,J.C.,Huang,Y.X.,Huang,J.Q.,Lei,X.,& Sun,L.H.(2023).Seleniumdeficiency-inducedmultipletissuedamage with dysregulation of immune and redox homeostasis in broiler chicks under heat stress. Science China Life Sciences, 66(9), 2056– 2069. https://doi.org/10.1007/s11427-022-2226-1 SUPPORTING INFORMATION Additional supporting information can be found online in the Supporting Information section at the end of this article. How to cite this article: Muiño,R.,Castillo,C.,Hernandez,J., Yeste,M.,&Benedito,J.L.(2024).Associationbetweenserum mineral levels and reproductive performance in primiparous dairy cows during the peripartum period. Reproduction in Domestic Animals, 59, e14578. https://doi.org/10.1111/ rda.14578 14390531, 2024, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/rda.14578 by Consorcio Interuniversitario Do Sistema Universitario De Galicia (Cisug), Wiley Online Library on [08/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License