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Nicolas Gengler - One of the best experts on this subject based on the ideXlab platform.
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Hot topic: Innovative Lactation-Stage-dependent prediction of methane emissions from milk mid-infrared spectra
Journal of Dairy Science, 2015Co-Authors: Annick Vanlierde, F Grandl, Birgit Gredler, Marie-laure Vanrobays, Eric Froidmont, Hélène Soyeurt, Frédéric Dehareng, Martin Kreuzer, Pierre Dardenne, M H Deighton, Sinead Mcparland, Elfed Lewis, Nicolas GenglerAbstract:The main goal of this study was to develop, apply, and validate a new method to predict an indicator for CH4 eructed by dairy cows using milk mid-infrared (MIR) spectra. A novel feature of this model was the consideration of Lactation Stage to reflect changes in the metabolic status of the cow. A total of 446 daily CH4 measurements were obtained using the SF6 method on 142 Jersey, Holstein, and Holstein-Jersey cows. The corresponding milk samples were collected during these CH4 measurements and were analyzed using MIR spectroscopy. A first derivative was applied to the milk MIR spectra. To validate the novel calibration equation incorporating days in milk (DIM), 2 calibration processes were developed: the first was based only on CH4 measurements and milk MIR spectra (independent of Lactation Stage; ILS); the second included milk MIR spectra and DIM information (dependent on Lactation Stage; DLS) by using linear and quadratic modified Legendre polynomials. The coefficients of determination of ILS and DLS equations were 0.77 and 0.75, respectively, with standard error of calibration of 63 g/d of CH4 for both calibration equations. These equations were applied to 1,674,763 milk MIR spectra from Holstein cows in the first 3 parities and between 5 and 365 DIM. The average CH4 indicators were 428, 444, and 448 g/d by ILS and 444, 467, and 471 g/d by DLS for cows in first, second, and third Lactation, respectively. Behavior of the DLS indicator throughout the Lactations was in agreement with the literature with values increasing between 0 and 100 DIM and decreasing thereafter. Conversely, the ILS indicator of CH4 emission decreased at the beginning of the Lactation and increased until the end of the Lactation, which differs from the literature. Therefore, the DLS indicator seems to better reflect biological processes that drive CH4 emissions than the ILS indicator. The ILS and DLS equations were applied to an independent data set, which included 59 respiration chamber measurements of CH4 obtained from animals of a different breed across a different production system. Results indicated that the DLS equation was much more robust than the ILS equation allowing development of indicators of CH4 emissions by dairy cows. Integration of DIM information into the prediction equation was found to be a good strategy to obtain biologically meaningful CH4 values from lactating cows by accounting for biological changes that occur throughout the Lactation.
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Within-herd effects of age at test day and Lactation Stage on test-day yields
Journal of dairy science, 2003Co-Authors: Jeanne Bormann, G.r. Wiggans, Tom Druet, Nicolas GenglerAbstract:Variance ratios were estimated for random within-herd effects of age at test day and Lactation Stage, on test-day yield and somatic cell score to determine whether including these effects would improve the accuracy of estimation. Test-day data starting with 1990 calvings for the entire US Jersey population and Holsteins from California, Pennsylvania, Wisconsin, and Texas were analyzed. Test-day yields were adjusted for across-herd effects using solutions from a regional analysis. Estimates of the relative variance (fraction of total variance) due to within-herd age effects were small, indicating that regional adjustments for age were adequate. The relative variances for within-herd Lactation Stage were large enough to indicate that accuracy of genetic evaluations could be improved by including herd Stage effects in the model for milk, fat, and protein, but not for somatic cell score. Because the within-herd Lactation Stage effect is assumed to be random, the effect is regressed toward the regional effects for small herds, but in large herds, Lactation curves become herd specific. Model comparisons demonstrated the greater explanatory power of the model with a within-herd-Stage effect as prediction error standard deviations were greater for the model without this effect. The benefit of the within-herd-Stage effects was confirmed in a random regression model by comparing variance components from models with and without random within-herd regressions and through log-likelihood ratio tests.
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Estimating effects of permanent environment, Lactation Stage, age, and pregnancy on test-day yield.
Journal of Dairy Science, 2002Co-Authors: Jeanne Bormann, G.r. Wiggans, Tom Druet, Nicolas GenglerAbstract:Test-day variances for permanent environmental effects within and across parities were estimated along with Lactation Stage, age, and pregnancy effects for use with a test-day model. Data were test-day records for calvings since 1990 for Jerseys and for Holsteins from California, Pennsylvania, Texas, and Wisconsin. Single-trait repeatability models were fitted for milk, fat, and protein test-day yields. Method R and a preconditioned conjugate gradient equation solver were used for variance component estimation because of large data sets. Test-day yields were adjusted for environmental effects of calving age, calving season, and milking frequency and for estimated breeding value (EBV) expressed on a daily basis. To assess the effect of adjustments, test-day yields also were analyzed without adjustment. For adjusted data, permanent environmental variances across parities relative to phenotypic variance ranged from 8.3 to 15.2% for milk, 4.4 to 8.3% for fat, and 6.9 to 11.0% for protein across regions and breeds; relative permanent environmental variances within parity ranged from 31.4 to 34.7% for milk, 18.2 to 22.3% for fat, and 28.3 to 29.1% for protein and were similar across regions and breeds. Adjustment for EBV reduced permanent environmental variance across parities and removed cow genetic variance. Relative permanent environmental variances within parity from unadjusted testday yields were nearly identical to those from adjusted test-day yields. For unadjusted test-day yields, heritabilities ranged from 0.19 to 0.30 for milk, 0.13 to 0.15 for fat, and 0.17 to 0.23 for protein. Adjustments for Lactation Stage, age at milking, previous days open, and days pregnant were estimated from adjusted test-day yields using the same single-trait repeatability models and variance ratios estimated for permanent environment
Zvonko Antunović - One of the best experts on this subject based on the ideXlab platform.
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Concentrations of mercury and other elements in ewes' milk: Effect of Lactation Stage.
Chemosphere, 2020Co-Authors: Zvonko Antunović, Boro Mioč, Zdenko Lončarić, Željka Klir, Ivan Širić, Valentino Držaić, Gordana Bukvić, Josip NovoselecAbstract:Abstract There is an increased production and demand for ewes´ milk in the Republic of Croatia, as well as globally. There is also a growing concern about its quality, since milk from farm animals may become contaminated with mercury and other toxic elements. Thus, the aim of this paper is to determine the influence of Lactation Stage on the ewes´ milk quality in western Croatia by considering concentrations of mercury and other elements in ewes´ milk. The research was conducted on 36 Travnik pramenka sheep during different Lactation Stages. The digested milk samples were analysed with continuous flow hydride generation technique by using inductively coupled plasma mass spectrometry. Samples were taken during 40th, 80th and 120th d of Lactation. Yield and quality of ewes’ milk was within Lactation curve. As Lactation progressed, significantly lower concentrations of Hg (on 80th d compared to 40th d) and of Cd (120th d compared to 80th d) were noted, and Hg on 120th d was below the detection limit. Concentrations of Ca and Cu were lower on the 120th d compared to 40th d, while P, Mg, Fe, Zn, Mn, and Se were lower on the 80th and 120th d compared to the 40th d. Concentrations of K, Mo, and Cr differed among all Stages of Lactation. Regarding toxic elements, the observed low concentrations of Hg, Co, Cd and As suggest that ewes´ milk in western Croatia is safe for human or animal consumption.
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Concentrations of selected toxic elements (cadmium, lead, mercury and arsenic) in ewe milk in dependence on Lactation Stage
Czech Journal of Animal Science, 2018Co-Authors: Zvonko Antunović, Ivan Bogut, Đuro Senčić, Miroslav Katić, Pero MijićAbstract:ABSTRACT: Biological investigations on ewes of Merinolandschaf breed (n = 10) were conducted by the 60th Lactation day during the summer on pasture. Ewe milk sampling was carried out on the 2nd ; 10th ; 30th and 60th Lactation day. An electrothermal technique was used to determine Cd and Pb concentrations in food and milk whereas As and Hg concentrations in food and milk were determined by a hydrid technique on an atomic absorption spectrophotometer. The investigation results indicate that concentrations of selected toxic elements in ewe milk varied in dependence on Lactation Stage. In colostrum (2nd Lactation day) Cd and Pb (0.011 and 0.035 mg/kg) concentrations were significantly higher (P 0.05) were found in milk Hg concentration in relation to Lactation Stage (from 0.021 to 0.026 mg/kg). The selected toxic elements appeared to be present in ewe milk in very low concentrations.
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Changes in macroelements, trace elements, heavy metal concentrations and chemical composition in milk of Croatian spotted goats during different Lactation Stages
International Journal of Dairy Technology, 2018Co-Authors: Zvonko Antunović, Boro Mioč, Ivica Marić, Josip Novoselec, Zdenko Lončarić, Željka KlirAbstract:The research was conducted on days 60, 90, 120 and 150 during the Lactation with the aim to determine the effect of Lactation Stage on the concentration of crucial elements and chemical composition in Croatian spotted goats’ milk. Milk yield significantly decreased (from 1.15 to 0.76 kg/day), while the concentration of Ca, Mg, P, Zn and Mo in the milk of the goats significantly increased during Lactation. The concentrations of Cr, Cd and Pb in milk were very low, with no significant deviations during Lactation. The quality of milk from Croatian spotted goats is adequate compared with other breeds in the surrounding area of Croatia.
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Effect of Lactation Stage on the concentration of essential and selected toxic elements in milk of Dubrovačka ruda - Croatian endangered breed
Mljekarstvo, 2016Co-Authors: Zvonko Antunović, Boro Mioč, Ivica Marić, Josip Novoselec, Zdenko Lončarić, Meri Engler, Darko Kerovec, Danijela Samac, Željka KlirAbstract:The aim of the present study was to determine the Lactation Stage effect on the concentration of essential and selected toxic elements in the sheep’s milk of Dubrovacka ruda. The research was conducted with 23 sheep, average age of 4 years, of 3rd Lactation, while the milk samples were taken during the early (60th day), middle (90th day) and late (120th day) Lactation Stage. The sheep were selected according to uniformed body development, adequate health status, body condition, equable age (4 years), parity (3rd Lactation), Stage of Lactation (±7 days) and litter size (single). Sheep were reared on the extensive Mediterranean pastures, reared indoors afterwards, fed with hay ad libitum and feed mixtures in average 0.5 kg/day. Milk sample was collected during morning milking from each sheep. The digested samples were analyzed with continuous flow hydride generation technique using inductively coupled plasma for Ca, Mg, K, P, Na, Cu, Fe, Zn, Mn, Ni, Mo, Co, Cr, Cd and Pb concentrations. Significant increase of Mg, Na, Se, Mn, Mo and Cd concentrations were found in milk as well as decrease of K concentration during the Lactation. Although the concentration of Ca, Cu, Cr and As in milk during the Lactation is increased, the differences between the Lactation Stages were not observed. Concentrations of P, Fe, Ni, Pb and Hg in milk of Dubrovacka ruda did not differ during the Lactation. The low concentrations of Cr, Cd, Pb, As, Hg in milk indicate the safety for consumers and preserved environment of Dubrovnik-Neretva County.
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Changes of heavy metal ConCentrations in goats milk DUring Lactation Stage in organiC breeDing
2012Co-Authors: Zvonko Antunović, S. Cavar, Boro Mioč, J. Novoselec, F. KrežmeAbstract:AntunoviC, Z., t. KLAPEC, S. CAvAR, B. MioC, J. novoSELEC and Z. KLiR, 2012. Changes of heavy metal concentrations in goats milk during Lactation Stage in organic breeding.
C Martínez-costa - One of the best experts on this subject based on the ideXlab platform.
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Impact of Lactation Stage, gestational age and mode of delivery on breast milk microbiota
Journal of Perinatology, 2014Co-Authors: P Khodayar-pardo, L Mira-pascual, Maria Carmen Collado, C Martínez-costaAbstract:Objective:There is an increasing evidence of the immunological role of breast milk (BM) microbiota on infant health. This study aims to analyze several determining factors of milk microbiota.Study Design:A total of 96 milk samples from 32 healthy mothers (19 preterm vs 13 at term gestations; and 15 vaginal deliveries vs 17 Cesarean sections) were longitudinally collected. Microbiota composition was studied by quantitative PCR and the influence of Lactation Stage, gestational age and delivery mode was evaluated.Result:Globally, Lactobacillus, Streptococcus and Enterococcus spp. were the predominant bacterial groups. Total bacteria, Bifidobacterium and Enterococcus spp. counts increased throughout the Lactation period. At all Lactation Stages, Bifidobacterium spp. concentration was significantly higher in milk samples from at term gestations than in preterm gestations. Higher bacterial concentrations in colostrum and transitional milk were found in Cesarean sections. Nevertheless, Bifidobacterium was detected more frequently in vaginal than in Cesarean deliveries.Conclusion:Lactation Stage, gestational age and delivery mode all influence the composition of several bacteria inhabiting BM: Bifidobacterium , Lactobacillus , Staphylococcus , Streptococcus and Enterococcus spp., and, consequently, may affect the infant’s early intestinal colonization.
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Impact of Lactation Stage, gestational age and mode of delivery on breast milk microbiota.
Journal of perinatology : official journal of the California Perinatal Association, 2014Co-Authors: P Khodayar-pardo, L Mira-pascual, Maria Carmen Collado, C Martínez-costaAbstract:There is an increasing evidence of the immunological role of breast milk (BM) microbiota on infant health. This study aims to analyze several determining factors of milk microbiota. A total of 96 milk samples from 32 healthy mothers (19 preterm vs 13 at term gestations; and 15 vaginal deliveries vs 17 Cesarean sections) were longitudinally collected. Microbiota composition was studied by quantitative PCR and the influence of Lactation Stage, gestational age and delivery mode was evaluated. Globally, Lactobacillus, Streptococcus and Enterococcus spp. were the predominant bacterial groups. Total bacteria, Bifidobacterium and Enterococcus spp. counts increased throughout the Lactation period. At all Lactation Stages, Bifidobacterium spp. concentration was significantly higher in milk samples from at term gestations than in preterm gestations. Higher bacterial concentrations in colostrum and transitional milk were found in Cesarean sections. Nevertheless, Bifidobacterium was detected more frequently in vaginal than in Cesarean deliveries. Lactation Stage, gestational age and delivery mode all influence the composition of several bacteria inhabiting BM: Bifidobacterium, Lactobacillus, Staphylococcus, Streptococcus and Enterococcus spp., and, consequently, may affect the infant's early intestinal colonization.
Henk Bovenhuis - One of the best experts on this subject based on the ideXlab platform.
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Genome-wide association study for genotype by Lactation Stage interaction of milk production traits in dairy cattle.
Journal of dairy science, 2020Co-Authors: Yachun Wang, Henk BovenhuisAbstract:Substantial evidence demonstrates that the genetic background of milk production traits changes during Lactation. However, most GWAS for milk production traits assume that genetic effects are constant during Lactation and therefore might miss those quantitative trait loci (QTL) whose effects change during Lactation. The GWAS for genotype by Lactation Stage interaction are aimed at explicitly detecting the QTL whose effects change during Lactation. The purpose of this study was to perform GWAS for genotype by Lactation Stage interaction for milk yield, lactose yield, lactose content, fat yield, fat content, protein yield, and somatic cell score to detect QTL with changing effects during Lactation. For this study, 19,286 test-day records of 1,800 first-parity Dutch Holstein cows were available and cows were genotyped using a 50K SNP panel. A total of 7 genomic regions with effects that change during Lactation were detected in the GWAS for genotype by Lactation Stage interaction. Two regions on Bos taurus autosome (BTA)14 and BTA19 were also significant based on a GWAS that assumed constant genetic effects during Lactation. Five regions on BTA4, BTA10, BTA11, BTA16, and BTA23 were only significant in the GWAS for genotype by Lactation Stage interaction. The biological mechanisms that cause these changes in genetic effects are still unknown, but negative energy balance and effects of pregnancy may play a role. These findings increase our understanding of the genetic background of Lactation and may contribute to the development of better management indicators based on milk composition.
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GWAS for genotype by Lactation Stage interaction for milk production
2019Co-Authors: Henk BovenhuisAbstract:The genetic background of milk production traits changes during Lactation. However, most genome-wide association study (GWAS) for milk production traits assume that genetic effects are constant during Lactation. The objective of this study was to identify those QTL whose effects on milk production traits change during Lactation. Test-day records were available for eight milk production traits on 1,829 first-parity Holstein cows. On average, each cow had 10.7 test-day records. The Lactation was divided in 26 Lactation Stages of 15 days each. After SNP filtering, 30,348 SNP remained for the GWAS. A GWAS specifically for SNP by Lactation Stage interaction was performed. Significance for the interaction term was determined based on permutation of the genotypes. Eleven genomic regions showing significant SNP by Lactation Stage interaction were identified indicating that the effects of those regions change during Lactation. The region on BTA 14 containing the diacylglycerol O-acyltransferase 1 (DGAT1) K232A polymorphism showed highly significant SNP by Lactation Stage interaction on milk yield, lactose yield, protein content and fat content. Another strong interaction was detected for a region on BTA 19 on lactose content. Less pronounced but significant interaction signals were detected for chromosomal regions on BTA 3, 9, 10b, and 27 on protein content, for regions on BTA 4 and 16 on fat yield and for regions on BTA 10a, 11, and 23 on fat content. The estimated effects for the lead SNP in the identified regions showed that the interaction was due to changes in SNP effects either in early or late Lactation. We hypothesize that different SNP effects in early Lactation are due to the negative energy balance which affects fat metabolism. Deviating SNP effects in late Lactation might be due to pregnancy. Our study demonstrated that a GWAS for genotype by Lactation Stage interaction can identify new genomic regions involved in milk production. This will help to elucidate the genetic and biological background of milk production. The performed methods can also be used for other longitudinal traits like body weight or egg production.
Josip Novoselec - One of the best experts on this subject based on the ideXlab platform.
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Concentrations of mercury and other elements in ewes' milk: Effect of Lactation Stage.
Chemosphere, 2020Co-Authors: Zvonko Antunović, Boro Mioč, Zdenko Lončarić, Željka Klir, Ivan Širić, Valentino Držaić, Gordana Bukvić, Josip NovoselecAbstract:Abstract There is an increased production and demand for ewes´ milk in the Republic of Croatia, as well as globally. There is also a growing concern about its quality, since milk from farm animals may become contaminated with mercury and other toxic elements. Thus, the aim of this paper is to determine the influence of Lactation Stage on the ewes´ milk quality in western Croatia by considering concentrations of mercury and other elements in ewes´ milk. The research was conducted on 36 Travnik pramenka sheep during different Lactation Stages. The digested milk samples were analysed with continuous flow hydride generation technique by using inductively coupled plasma mass spectrometry. Samples were taken during 40th, 80th and 120th d of Lactation. Yield and quality of ewes’ milk was within Lactation curve. As Lactation progressed, significantly lower concentrations of Hg (on 80th d compared to 40th d) and of Cd (120th d compared to 80th d) were noted, and Hg on 120th d was below the detection limit. Concentrations of Ca and Cu were lower on the 120th d compared to 40th d, while P, Mg, Fe, Zn, Mn, and Se were lower on the 80th and 120th d compared to the 40th d. Concentrations of K, Mo, and Cr differed among all Stages of Lactation. Regarding toxic elements, the observed low concentrations of Hg, Co, Cd and As suggest that ewes´ milk in western Croatia is safe for human or animal consumption.
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Changes in macroelements, trace elements, heavy metal concentrations and chemical composition in milk of Croatian spotted goats during different Lactation Stages
International Journal of Dairy Technology, 2018Co-Authors: Zvonko Antunović, Boro Mioč, Ivica Marić, Josip Novoselec, Zdenko Lončarić, Željka KlirAbstract:The research was conducted on days 60, 90, 120 and 150 during the Lactation with the aim to determine the effect of Lactation Stage on the concentration of crucial elements and chemical composition in Croatian spotted goats’ milk. Milk yield significantly decreased (from 1.15 to 0.76 kg/day), while the concentration of Ca, Mg, P, Zn and Mo in the milk of the goats significantly increased during Lactation. The concentrations of Cr, Cd and Pb in milk were very low, with no significant deviations during Lactation. The quality of milk from Croatian spotted goats is adequate compared with other breeds in the surrounding area of Croatia.
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Effect of Lactation Stage on the concentration of essential and selected toxic elements in milk of Dubrovačka ruda - Croatian endangered breed
Mljekarstvo, 2016Co-Authors: Zvonko Antunović, Boro Mioč, Ivica Marić, Josip Novoselec, Zdenko Lončarić, Meri Engler, Darko Kerovec, Danijela Samac, Željka KlirAbstract:The aim of the present study was to determine the Lactation Stage effect on the concentration of essential and selected toxic elements in the sheep’s milk of Dubrovacka ruda. The research was conducted with 23 sheep, average age of 4 years, of 3rd Lactation, while the milk samples were taken during the early (60th day), middle (90th day) and late (120th day) Lactation Stage. The sheep were selected according to uniformed body development, adequate health status, body condition, equable age (4 years), parity (3rd Lactation), Stage of Lactation (±7 days) and litter size (single). Sheep were reared on the extensive Mediterranean pastures, reared indoors afterwards, fed with hay ad libitum and feed mixtures in average 0.5 kg/day. Milk sample was collected during morning milking from each sheep. The digested samples were analyzed with continuous flow hydride generation technique using inductively coupled plasma for Ca, Mg, K, P, Na, Cu, Fe, Zn, Mn, Ni, Mo, Co, Cr, Cd and Pb concentrations. Significant increase of Mg, Na, Se, Mn, Mo and Cd concentrations were found in milk as well as decrease of K concentration during the Lactation. Although the concentration of Ca, Cu, Cr and As in milk during the Lactation is increased, the differences between the Lactation Stages were not observed. Concentrations of P, Fe, Ni, Pb and Hg in milk of Dubrovacka ruda did not differ during the Lactation. The low concentrations of Cr, Cd, Pb, As, Hg in milk indicate the safety for consumers and preserved environment of Dubrovnik-Neretva County.