The ability of a handheld near-infrared spectrometer to do a rapid quality assessment of bovine colostrum, including the immunoglobulin G concentration.

Portable infrared-based instruments have made important contributions in different research fields. Within the dairy supply chain, for example, most of portable devices are based on near-infrared spectroscopy (NIRS) and are nowadays an important support for farmers and operators of the dairy sector, allowing fast and real-time decision-making, particularly for feed and milk quality evaluation and animal health and welfare monitoring. The affordability, portability, and ease of use of these instruments have been pivotal factors for their implementation on farm. In fact, pocket-sized devices enable nonexpert users to perform quick, low-cost, and nondestructive analysis on various matrixes without complex preparation. Because bovine colostrum (BC) quality is mostly given by the IgG level, evaluating the ability of portable NIRS tools to measure antibody concentration is advisable. In this study we used the wireless device SCiO manufactured by Consumer Physics Inc. (Tel Aviv, Israel) to collect BC spectra and then attempt to predict IgG concentration and gross and fine composition in individual samples collected immediately after calving (<6 h) in primiparous and pluriparous Holstein cows on 9 Italian farms. Chemometric analyses revealed that SCiO has promising predictive performance for colostral IgG concentration, total Ig concentration, fat, and AA. The coefficient of determination of cross-validation (R2CV) was in fact ≥0.75). Excellent accuracy was observed for dry matter, protein, and S prediction in cross-validation and good prediction ability in external validation (R2CV ≥ 0.93; the coefficient of determination of external validation, R2V, was ≥0.82). Nonetheless, SCiO's ability to discriminate between good- and low-quality samples (IgG ≥ vs. < 50 g/L) was satisfactory. The affordable cost, the accurate predictions, and the user-friendly design, coupled with the increased interest in BC within the dairy sector, may boost the collection of extensive BC data for management and genetic purposes in the near future.

Comparison of turbidometric immunoassay and brix refractometry to radial immunodiffusion for assessment of colostral immunoglobulin concentration in beef cattle.

BACKGROUND: Colostral immunoglobulin G (IgG) concentration is critical to the attainment of adequate transfer of passive immunity in cattle, however, studies comparing available tools for measurement of colostral IgG concentration in beef cattle are limited. OBJECTIVES: To report the agreement between 3 commercially available tests for evaluating IgG concentration in beef colostrum. ANIMALS: Two hundred six beef-breed cows hospitalized for calving management or dystocia. METHODS: Retrospective study to assess IgG of whole colostrum measured stall-side via turbidimetric immunoassay (TI) and brix refractometry (BRIX), compared to fat separated (FS) analysis via single radial-immunodiffusion (RID; reference standard), TI-FS and BRIX-FS. Test performance was assessed using Passing Bablock regression, Bland-Altman analysis, and area under the curve to determine optimal thresholds. RESULTS: Correlation between RID and TI-FS, BRIX-FS, or BRIX was similar (Spearman's ρ = 0.717, 0.715, 0.716, respectively) but correlation for TI was poor (ρ = 0.586). Regression analysis identified a substantial constant (-214.75 [CI: -272.03 to -178.07]) and proportional (13.24 [CI: 11.81-15.37]) bias between the RID and TI-FS which was similar for TI. TI-FS concentrations of 28.47, 38.75, and 50.62 g/L, BRIX-FS of ≤21.9%, ≤24.0%, and ≤27.4%, and BRIX of ≤21.3%, ≤23.8%, and ≤26.4% indicated IgG concentrations <50, <100, and <150 g/L, respectively; appropriate cutoffs for TI could not be generated. CONCLUSIONS AND CLINICAL IMPORTANCE: Both TI and TI-FS demonstrated a large constant and proportional bias compared to RID; BRIX and BRIX-FS were well correlated with RID and remain a reliable method for estimation of colostral IgG concentration in beef cattle.

Polychlorinated biphenyls (PCBs) in the colostrum samples from the Yangtze River Region: Exposure profile and risk assessment.

Polychlorinated biphenyls (PCBs) may transfer into the neonates through the placental transfer and via breastfeeding after the delivery, thus might be harmful to the infant. Sixty colostrum samples in the Yangtze River Region were collected to investigate the concentration, distribution pattern, and enantiomer characteristic of the PCB exposure. Among all samples, over 90% of pollutants were tetra-to hepta-chlorinated PCBs. The sum concentration of the PCB was 512 (IQR: 322-856) ng g-1 lipid weight. Enantiomer fraction (EF) of PCB 95 and PCB 149 was found lower than the racemic value, while EFs of PCB 45 and PCB 136 were found higher and near-racemic state, respectively. The concentration pattern and enantiomeric properties of the PCBs indicated that the mothers from Mianyang had a recent exposure to PCBs. Among all samples, similar exposure and metabolic pathways of the PCB congeners were observed. PCB exposure showed no significant correlation with the birth outcome of the infants, but 43.3% of the infants have potential health risks via breastfeeding.

Assessment of Brix refractometry to estimate immunoglobulin G concentration in beef cow colostrum.

BACKGROUND: Brix refractometry can be used to assess colostral immunoglobulin G (IgG) concentration, but studies identifying Brix percentages to detect high- and low-IgG colostrum are lacking for beef cows and interlaboratory agreement is unknown. OBJECTIVES: Evaluate Brix refractometer performance and interlaboratory agreement for assessing beef cow colostrum IgG concentration, including determination of thresholds to identify colostrum containing IgG concentrations <100 g/L and ≥150 g/L. ANIMALS: Beef cows (n = 416) from 11 cow-calf operations in Alberta, Canada. METHODS: Colostral IgG concentrations were measured using radial immunodiffusion (RID) and estimated by Brix refractometry for this retrospective study. Spearman correlation coefficients were assessed between RID and Brix refractometry. Likelihood ratios and misclassification cost-term analysis were used to determine optimal Brix percentages for detecting colostrum containing IgG concentrations <100 g/L and ≥150 g/L. Concordance correlation coefficient (CCC) and Bland-Altman analyses were performed for Brix percentages obtained at 3 different laboratories. RESULTS: Brix percentages obtained at 3 laboratories were positively correlated with IgG results (r = 0.72, 0.68, and 0.76, respectively). Colostrum Brix percentages of <24% and ≥30% were optimal for indicating IgG concentrations of <100 g/L and ≥150 g/L, respectively. Interlaboratory agreement was substantial, with CCC ranging from 0.89 to 0.96 and Bland-Altman analysis showing small mean differences (-1.2% to 0.09% Brix) and narrow limits of agreements (-4.8% to 2.4% Brix) among laboratories. CONCLUSIONS AND CLINICAL IMPORTANCE: Brix refractometry shows good potential for reliably estimating IgG concentrations in beef cow colostrum across multiple laboratories and can be recommended to aid colostrum management decisions on farms.

Quantitative assessment of German Holstein dairy cattle colostrum and impact of thermal treatment on quality of colostrum viscosity and immunoglobulins.

OBJECTIVE: This study aimed to determine the color, fat, viscosity, IgG concentration, %Brix and refractive index of fresh postpartum colostrum of German Holstein dairy cattle and assess the impact of different thermal treatments on the visual and dynamic viscosity, in association to IgG concentration, of colostrum that can be used for pasteurization process. RESULTS: Of the total 40 fresh postpartum colostrum, the color of colostrum (ranging from white-pale yellow to yellow and dark-yellowish), fat (1.4-8.2 100 g-1), IgG (4-116 mg mL-1), %Brix (8.5-35.4%), refractive index (1.3454-1.3905 nD), visual (ranging from watery to liquid and thick) and dynamic (4.9-219 cp) viscosity, were recorded. Statistical analysis between visual and dynamic viscosity of fresh colostrum showed significant correlation coefficients (rs = 634). Moreover, a significant correlation between viscosity and three IgG concentrations was also observed. Heat-treated colostrum showed dynamic viscosity ranged from 25 to 3066 cP, where dynamic viscosity of colostrum before- and after heat-treatment showed no significant correlation. Treated colostrum at 60 °C/60 min and 63.5 °C/30 min containing IgG concentration ≤ 80 mg mL-1 and ≤ 68 mg mL-1 showed no significant change in the viscosity and can successfully be applied for pasteurization of first postpartum colostrum.

Immunoglobulins content in colostrum, transitional and mature milk of Bangladeshi mothers: Influence of parity and sociodemographic characteristics.

BACKGROUND: The study investigated the concentration of IgA, IgM and IgG in colostrum, transitional and mature milk and the effect of parity, age, BMI and family income on secreted immunoglobulin contents of human milk. METHODS: Sequential samples of colostrum, transitional and mature milk were collected from 38 women. Enzymelinked immunosorbent assay was used to analyse the immunoglobulin concentrations. RESULTS: The study revealed that IgA was the dominant immunoglobulin and mean concentration in colostrum, transitional and mature milk was 5.92 ± 1.50 g/L, 3.85 ± 0.64 g/L and 3.72 ± 0.68 g/L, respectively. Both IgA and IgM levels of colostrum decreased significantly in both transitional (P = 0.000) and mature milk (P = 0.000), while the concentration of IgG rises significantly in them (colostrum vs. transitional milk, P = 0.000; and colostrum vs. mature milk P = 0.011). While maternal age, BMI and family income had no significant influence on the immunoglobulin levels at different stages of lactation, parity showed significant influence on IgG (P = 0.03) and IgM (P = 0.05) levels of transitional milk and IgA level of colostrum (P = 0.05). CONCLUSION: The findings suggest that immunoglobulin composition in breast milk is strongly associated with stage of lactation and is likely to be more susceptible to parity than BMI and socioeconomic characteristics.

[Quality Assessment of Bovine and Equine Colostrum - An Overview]. / Qualitätsbeurteilung von bovinen und equinen Kolostrum ­ Eine Übersicht.

INTRODUCTION: Good quality colostrum intake is essential for passive immunity in neonatal calf and foals. The quality of colostrum depends on its IgG content. Since in practice the possibilities for a direct determination of these parameter are limited, an estimation of colostrum quality is often based on its biophysical properties. The simple methodology allows to perform measurements directly on site and immediately after birth. The biophysical properties included in the current review are density, refractive index, relative density, viscosity, pH, and color. The determination of the density of bovine colostrum is a common method for the evaluation of the IgG content in practice since it correlates with IgG. Density of bovine colostrum should be 1047 g/l. Different colostrometers are available for the measurement. This method is also used in the horses. Density of equine colostrum should be 1060 g/l. Refractive index or the relative density by refractometer has been proven to correlate with the IgG and is an established method in cattle and horses. Good bovine colostrum should have an index of 22% brix and equine colostrum 23% brix. Although not yet established in practice an additional methodology would be the determination viscosity of bovine colostrum. Viscosity could be measured with an outlet cup. A relationship between viscosity and IgG has demonstrated. Sufficient data for this method is missing for equine colostrum. Color and pH are not suitable for estimating the IgG content.

INTRODUCTION: La prise de colostrum de bonne qualité est essentielle pour la construction d'une immunité passive chez le veau et le poulain nouveau-nés. La qualité du colostrum dépend de sa teneur en IgG. Comme dans la pratique les possibilités de détermination directe de ce paramètre sont limitées, une estimation de la qualité du colostrum est souvent basée sur ses propriétés biophysiques. Grâce à une méthodologie simple, la mesure peut généralement être effectuée directement sur place et immédiatement après la naissance. Les propriétés biophysiques incluses dans cette revue sont la densité, l'indice de réfraction, la densité relative, la viscosité, le pH et la couleur. La détermination de la densité du colostrum bovin est en pratique une méthode courante pour évaluer la teneur en IgG, car la densité est en corrélation avec la teneur en IgG. La densité du colostrum doit être d'au moins 1047 g/l. Différents colostromètres sont disponibles pour cette mesure. Cette méthode est également utilisée chez le cheval. La densité du colostrum équin doit être d'au moins 1060 g/l. La détermination de l'indice de réfraction ou de la densité relative au moyen d'un réfractomètre est une procédure établie chez les bovins et les chevaux, car une corrélation claire avec la teneur en IgG est prouvée. Pour être considéré comme bon, le colostrum bovin doit atteindre une valeur de 22% et le colostrum équin une valeur de 23% sur l'échelle de Brix. L'évaluation du colostrum bovin par viscosité est une autre approche qui doit encore être mise en pratique. Là encore, une relation entre la viscosité et la teneur en IgG pourrait être prouvée. La mesure de la viscosité peut être effectuée à l'aide d'une coupe d'écoulement. Chez le cheval, on ne dispose pas encore de données suffisantes sur cette méthode. La valeur du pH et la couleur ne conviennent pas pour estimer la teneur en IgG.

Vitamin A nutritional status in high- and low-income postpartum women and its effect on colostrum and the requirements of the term newborn / Estado nutricional de vitamina A de puérperas de alta e baixa renda e seu efeito sobre o colostro e a necessidade do recém-nascido a termo

Abstract Objective To evaluate the vitamin A status in serum and colostrum of postpartum women with different socioeconomic status, comparing the colostrum retinol supply with the vitamin A requirement of the newborn. Methods Cross-sectional study conducted with 424 postpartum women. Vitamin A maternal dietary intake was estimated using a food frequency questionnaire. Colostrum and serum retinol levels were measured by high performance liquid chromatography (HPLC). Serum retinol concentrations <20 µg/dL were indicative of vitamin A deficiency (VAD). Vitamin A levels provided by colostrum <400 µgRAE/day were considered as insufficient for term newborns. Results The mean maternal vitamin A intake during pregnancy was 872.2 ± 639.2 µgRAE/day in low-income women and 1169.2 ± 695.2 µgRAE/day for high-income women (p < 0.005). The prevalence of vitamin A deficiency was 6.9% (n = 18) in the low-income group and 3.7% (n = 6) in the high-income group. The estimated mean retinol intake by infants of the high- and low-income mothers were 343.3 µgRAE/day (85.8% AI) and 427.2 µgRAE/day (106.8% AI), respectively. Conclusions Serum vitamin A deficiency was considered a mild public health problem in both populations; however, newborns of low-income women were more likely to receive lower retinol levels through colostrum when compared with newborns of high-income mothers.

Resumo Objetivo Avaliar o estado nutricional de vitamina A no soro e colostro de puérperas com diferentes condições de renda, comparando os níveis de retinol fornecido através do colostro coma necessidade de vitamina A do recém-nascido. Métodos Estudo transversal com 424 mulheres pós-parto. A ingestão de vitamina A dietética pelas mães foi estimada através de um questionário de frequência do consumo alimentar. Os níveis retinol no soro e colostro foram quantificados por cromatografia líquida de alta eficiência (CLAE). Concentrações de retinol <20 µg/dL no soro foram indicativas de vitamin A deficiency. Os níveis de vitamina A fornecidas pelo colostro < 400 µg/RAE/dia foram considerados insuficientespara os recém-nascidos a termo. Resultados A ingestão média de vitamina A das mães durante a gravidez foi de 872,2 ± 639,2 µgRAE/dia em mulheres de baixa renda e 1169,2 ± 695,2 µgRAE/dia em mulheresde alta renda (p < 0,005). A prevalência de vitamin A deficiency foi de 6,9% (n = 18) no grupo de baixa renda e de 3,7% (n = 6) no grupo de alta renda. A estimativa dos valores médios de ingestão de retinol por lactentes de mães de baixa e alta renda foi de 343,3 µg/RAE/dia (85,8%AI) e 427,2 µg/RAE/dia (106,8% AI), respectivamente. Conclusões A vitamin A deficiency no soro foi prevalente em ambas as populações, entretanto, recém-nascidos de mães de baixa renda foram mais propensos a receberem níveis inferiores de retinol no colostro em comparação com recém-nascidos de mães de alta renda.

Vitamin A nutritional status in high- and low-income postpartum women and its effect on colostrum and the requirements of the term newborn.

OBJECTIVE: To evaluate the vitamin A status in serum and colostrum of postpartum women with different socioeconomic status, comparing the colostrum retinol supply with the vitamin A requirement of the newborn. METHODS: Cross-sectional study conducted with 424 postpartum women. Vitamin A maternal dietary intake was estimated using a food frequency questionnaire. Colostrum and serum retinol levels were measured by high performance liquid chromatography (HPLC). Serum retinol concentrations <20µg/dL were indicative of vitamin A deficiency (VAD). Vitamin A levels provided by colostrum <400µgRAE/day were considered as insufficient for term newborns. RESULTS: The mean maternal vitamin A intake during pregnancy was 872.2±639.2µgRAE/day in low-income women and 1169.2±695.2µgRAE/day for high-income women (p<0.005). The prevalence of vitamin A deficiency was 6.9% (n=18) in the low-income group and 3.7% (n=6) in the high-income group. The estimated mean retinol intake by infants of the high- and low-income mothers were 343.3µgRAE/day (85.8% AI) and 427.2µgRAE/day (106.8% AI), respectively. CONCLUSIONS: Serum vitamin A deficiency was considered a mild public health problem in both populations; however, newborns of low-income women were more likely to receive lower retinol levels through colostrum when compared with newborns of high-income mothers.

Retinol and α-Tocopherol in the Breast Milk of Women after a High-Risk Pregnancy.

BACKGROUND: There is scant information about whether, after a high-risk pregnancy, breast milk provides enough vitamins for assuring satisfactory bodily reserves in newborns. OBJECTIVE: To comparatively evaluate, in women with high-risk and normal pregnancy, the concentration of retinol and α-tocopherol in breast milk. METHODS: This cross-sectional, analytical study was evaluated with reverse-phase high-performance liquid chromatography (HPLC). Informed consent was signed by 95 mothers with a high-risk pregnancy and 32 mothers with a normal pregnancy. From the mothers with a high-risk pregnancy were obtained: 23 samples of colostrum, 24 of transitional milk, and 48 of mature milk. From the normal pregnancy group, 32 mature milk samples were collected. Pregestational Body Mass Index (BMI) and the gestational weight gain were noted. Models of logistic regression were constructed to identify the variables related to a low concentration of either retinol or α-tocopherol in breast milk. RESULTS: The concentration of retinol and α-tocopherol in mature milk was 60 (interquartile range (IQR), 41-90) and 276 (103-450) µg/dL, respectively, for the high-risk pregnancy group, and 76 (65-91) and 673 (454-866) µg/dL, respectively, for the normal pregnancy group (p = 0.001). The concentration of retinol and α-tocopherol was similar in the subgroups of mothers with different disorders during gestation. A clear correlation was found between a greater pregestational weight and a lower concentration of retinol (Rho = -0.280, p = 0.006), and between α-tocopherol and retinol in all cases (Rho = 0.463, p = 0.001). Among women having a high-risk pregnancy, those delivering prematurely rather than carrying their pregnancy to term had a reduced concentration of retinol (54 (37-78) vs. 70 (49-106) µg/dL; p = 0.002) and a tendency to a lower concentration of α-tocopherol in breast milk (185 (75-410) vs. 339 (160-500) µg/dL; p = 0.053). Compared to mothers with a normal pregnancy, those with a high-risk pregnancy (whether carried to term or ending in preterm delivery) exhibited a reduced concentration of retinol in mature milk (p = 0.003), as well as a tendency to a lower concentration of α-tocopherol (p = 0.054). CONCLUSION: Even though the women in the high-risk pregnancy group showed a deficiency of vitamins A and E in their breast milk, the unique biological benefits of this milk justify the promotion of breast feeding as the optimal method of nourishing neonates and infants. In these cases, it should be recommended that the woman increase her consumption of certain nutrients during pregnancy. Additionally, after childbirth mothers should consider the use of supplements to produce milk of adequate quality and thus meet the needs of the baby and prevent any deficiency in micronutrients.

The effect of vitamin A supplementation with 400 000 IU vs 200 000 IU on retinol concentrations in the breast milk: A randomized clinical trial.

BACKGROUND & AIMS: The vitamin A nutritional status is marginal for most of the newborns, and the prevention of that deficiency is promoted by breastfeeding. The Ministry of Health of Brazil established the National Vitamin A Supplementation Program, giving mega-doses of this nutrient to women right after delivery, in order to provide adequate vitamin A content in the breast milk and The International Vitamin A Consultative Group has supported the recommendation, to supplement with 400 000 IU of VA immediately after delivery. This study compares retinol concentrations in breast milk (colostrum, 2 and 4 months) from mothers supplemented during immediate postpartum with 400 000 IU versus 200 000 IU of vitamin A. METHODS: A randomized, controlled, triple-blind trial, conducted in two public maternities in Recife, Northeast Brazil. Two hundred and ten mothers were recruited and allocated into two treatment groups: 400 000 IU or 200 000 IU of Vitamin A and monitored for 4 months. RESULTS: There was no significant difference between retinol concentrations in breast milk between treatment groups (400 000 IU vs 200 000 IU) in the studied period: 2 months (p = 0.790) and 4 months (p = 0.279), although a progressive reduction of concentrations throughout the study was observed in both treatment groups, 400 000 IU (p < 0.0001) and 200 000 IU (p < 0.0001). CONCLUSIONS: The absence of an additional effect of a higher dosage justifies the 200 000 IU supplementation, according to the World Health Organization. Registered under ClinicalTrials.gov Identifier No. NCT00742937.

Rapid assessment of bovine colostrum quality: How reliable are transmission infrared spectroscopy and digital and optical refractometers?

The objectives of this study were to evaluate the performance of the transmission infrared (IR) spectroscopic method and digital and optical Brix refractometers for measurement of colostral IgG concentration and assessment of colostrum quality of dairy cows. Colostrum samples (n = 258) were collected from Holstein cows on 30 commercial dairy farms in Nova Scotia and Newfoundland, Canada. Colostral IgG concentrations of 255 samples were measured by the reference radial immunodiffusion (RID) assay and IR spectroscopy. The Brix scores were determined on 240 of these samples using both the digital and optical Brix refractometers. Approximately half (48%) of the colostrum samples had RID IgG concentrations <50 g/L, which was the cut-point for poor quality. The correlation between RID and IR IgG concentrations was 0.88. The correlations between RID IgG concentration and Brix scores, as determined by the digital and optical refractometers, were 0.72 and 0.71, respectively. The optimal cutoff levels for distinguishing good- and poor-quality colostrum using IR spectroscopy, and digital and optical Brix refractometers were at 35 g/L and 23% Brix, respectively. The IR spectroscopy showed higher sensitivity (90%) and specificity (86%) than the digital (74 and 80%, respectively) and optical (73 and 80%, respectively) Brix refractometers for assessment of colostrum quality, as compared with RID. In conclusion, the transmission-IR spectroscopy is a rapid and accurate method for assessing colostrum quality, but is a laboratory-based method, whereas Brix refractometers were less accurate but could be used on-farm.

Assessment of arsenic in colostrum and cord serum and risk exposure to neonates from an island population in China.

Arsenic (As) has been proven to be highly toxic to humans, but limited attention has focused on exposure levels and potential risks to mother-neonate pairs of coastal populations. This study was conducted by examining the As concentration in colostrum and umbilical cord serum collected from 106 mother-neonate pairs living on Shengsi Island, facing the Yangtze River estuary and Hangzhou Bay in China. Average concentrations of total As in colostrum and cord serum were 18.51 ± 7.00 and 19.83 ± 10.50 µg L-1. One-way ANOVA analysis showed delivered ages and source of drinking water played significant roles in influencing the maternal exposure patterns. Correlation analysis indicated a significantly positive association between As concentrations in colostrum and cord serum. Multivariable linear regression models adjusted for other confounders clarified the dose-response relationship with a coefficient value of 0.23 and a 95 % confidence interval of (0.006, 0.492); p < 0.05. The calculated daily intake of total As for neonates through breastfeeding was in the range from 0.413 to 3.65 µg kg-1 body weight, and colostrum As, especially the most toxic species, inorganic arsenic (iAs), would pose a risk to neonates.

Assessment of different methods to estimate bovine colostrum quality on farm.

AIMS: To evaluate two different hydrometers and an optical and a digital Brix refractometer for the assessment of bovine colostrum quality, in terms of accuracy and precision compared with the measurement of IgG concentrations using radial immunodiffusion (RID), and to evaluate the reliability and repeatability of the Brix refractometers. METHODS: To determine reliability and repeatability, 145 colostrum samples were tested by two independent observers twice, using the optical and digital Brix refractometers. A further 193 colostrum samples from Holstein cows were collected on one commercial dairy farm at first milking and tested with two hydrometers and an optical and digital Brix refractometer. An aliquot of each sample was frozen for RID measurement of IgG concentrations and samples were classified as poor (≤50 g IgG/L) or good (>50 g IgG/L) quality colostrum. Intraclass correlation coefficients (ICC) were used to determine inter- and intra-observer reliability and repeatability. Optimised cut-off values for the four devices were determined using receiver operating characteristics (ROC) analysis with the RID results as the reference. Using these cut-offs, sensitivities and specificities for determining good quality colostrum were calculated. RESULTS: The ICC for inter-observer reliability was 0.98 for the optical Brix refractometer, and for intra-observer repeatability was 0.97 and 0.98 for the optical and the digital Brix refractometers, respectively. For the 193 colostrum samples, 67 (34.7%) had concentrations of IgG ≤50 g/L determined by RID. Optimised cut-off values evaluated by ROC analysis were higher for all devices compared with manufacturer reference or previously published values. Using these values, the sensitivities for the two hydrometers, and the optical and the digital Brix refractometers were 0.73, 0.71, 0.56 and 0.79, respectively; specificities were 0.72, 0.61, 0.90 and 0.69, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The Brix refractometers provided the most accurate assessment of colostrum quality of the devices evaluated, and demonstrated excellent precision in terms of repeatability. To provide optimal health for newborn calves, a sufficient intake of good quality colostrum is essential. The Brix refractometers provide rapid, convenient tools for classification of colostrum quality.

Refractometer assessment of colostral and serum IgG and milk total solids concentrations in dairy cattle.

BACKGROUND: Estimation of the quantity of colostral IgG or serum IgG absorbed following ingestion of colostrum by calves is essential for monitoring the effectiveness of colostrum feeding practices on dairy farms. Milk total solids concentrations determination is a critical part of quality assessment of nonsaleable whole milk prior to feeding to calves. To date, on-farm methods to assess colostral IgG, serum IgG or milk total solids concentrations have been performed separately with various instruments. The objective of this study was to evaluate the diagnostic performance of a single electronic, hand-held refractometer for assessing colostral and serum IgG concentrations and milk total solids in dairy cattle. Colostral IgG, serum IgG and milk total solids concentrations were determined by the refractometer. Corresponding analysis of colostral and serum IgG concentrations were determined by radial immunodiffusion (RID) while milk total solids were determined by spectrophotometry. Sensitivity and specificity of the refractometer for colostrum and serum samples were calculated as determined by RID. Sensitivity and specificity of the refractometer for milk samples was calculated as determined by spectrophotometry. RESULTS: The sensitivity of the refractometer was 1 for colostral IgG, serum IgG and milk total solids determinations. Specificity of the refractometer was 0.66, 0.24 and 0 for colostral IgG, serum IgG and milk total solids determinations, respectively. The refractometer underestimated colostral IgG, serum IgG and milk total solids concentrations compared to the concentrations determined by RID or spectrophotometry. CONCLUSIONS: The refractometer was an acceptable, rapid, convenient on-farm method for determining colostral IgG and milk total solids. The refractometer was not an acceptable method for determination of serum IgG concentrations as it severely underestimated the serum IgG concentrations.

Correlation of serum IgG concentration in foals and refractometry index of the dam's pre- and post-parturient colostrums: an assessment for failure of passive transfer in foals.

The object of this study was to evaluate the usefulness of measuring the differences in the values of the serum total protein (DVSTP) concentration of foals and the refractometry index (DVRI) of the milk of dams before and after nursing of the colostrum for assessing failure of passive transfer (FPT) in foals. Serum samples from 31 foals were collected before the first nursing and other 1 to 6 times between 4 and 24 hr after birth. Paired colostrum and milk samples were collected from 14 of their dams at the same time. Serum samples were analyzed for IgG concentration using a single radial immunodiffusion (SRID) test (98 samples) and total protein concentration using a temperature-compensating refractometer (98 samples). Colostrum and milk samples were analyzed for refractometry index (RI) using a Brix refractometer (71 samples). DVSTP concentration and DVRI were significantly correlated with serum IgG concentration. The negative predictive values (NPVs) of DVSTP concentration for detecting serum IgG concentrations<400 mg/dl and<800 mg/dl were 98.2% and 91.3% when the cutoff value is set to 0.4 mg/dl and 0.8 mg/dl, respectively. Furthermore, the NPVs of DVRI for detecting serum IgG concentrations<400 mg/dl and<800 mg/dl were 97.3% and 96.3% when the cutoff value is set to 6% and 10%, respectively. The results suggest that measurement of DVRI is useful in assessing FPT as an initial "stall-side" screening test, because it is easy, inexpensive to perform and allows for rapid interpretation.

Breastfeeding, long-chain polyunsaturated fatty acids in colostrum, and infant mental development.

BACKGROUND: Breastfeeding has been associated with improved neurodevelopment in children. However, it remains unknown to what extent nutritional advantages of breast milk may explain this relationship. OBJECTIVE: We assessed the role of parental psychosocial factors and colostrum long-chain polyunsaturated fatty acid (LC-PUFA) levels in the relationship between breastfeeding and children's neurodevelopment. METHODS: A population-based birth cohort was established in the city of Sabadell (Catalonia, Spain) as part of the INMA-INfancia y Medio Ambiente Project. A total of 657 women were recruited during the first trimester of pregnancy. Information about parental characteristics and breastfeeding was obtained by using a questionnaire, and trained psychologists assessed mental and psychomotor development by using the Bayley Scales of Infant Development in 504 children at 14 months of age. RESULTS: A high percentage of breastfeeds among all milk feeds accumulated during the first 14 months was positively related with child mental development (0.37 points per month of full breastfeeding [95% confidence interval: 0.06-0.67]). Maternal education, social class, and intelligence quotient only partly explained this association. Children with a longer duration of breastfeeding also exposed to higher ratios between n-3 and n-6 PUFAs in colostrum had significantly higher mental scores than children with low breastfeeding duration exposed to low levels. CONCLUSIONS: Greater levels of accumulated breastfeeding during the first year of life were related to higher mental development at 14 months, largely independently from a wide range of parental psychosocial factors. LC-PUFA levels seem to play a beneficial role in children's mental development when breastfeeding levels are high.

[Relationship between lead levels in colostrum, dietary intake, and socioeconomic characteristics of puerperal women in Goiânia, Brazil]. / Relação entre níveis de chumbo no colostro, consumo alimentar e características socioeconômicas de puérperas em Goiânia, Brasil.

OBJECTIVE: To estimate the levels of lead in human colostrum and investigate whether they are correlated with dietary intake and socioeconomic factors in puerperal women. METHOD: This cross-sectional study was carried out with 80 puerperal women from a maternity hospital in Goiânia, Brazil. Data were collected between July and December 2008. A questionnaire was used to collect socioeconomic and lifestyle information. A dietary intake frequency questionnaire was also applied. After that, colostrum samples were collected and analyzed using flame atomic absorption spectrometry to quantify lead levels. The correlation between lead levels, socioeconomic variables, and dietary intake was calculated. RESULTS: The mean concentration of lead in colostrum samples was 6.88 µg/L, and the median concentration was 4.65 µg/L. There was no association between socioeconomic aspects and lead levels. The intake of saturated fatty acids, eggs, pork meats, chicken, and chicken products (r = -0.26 and P = 0.020) was inversely correlated with the levels of lead in human colostrum, whereas the intake of squash (r = 0.26; P = 0.019) and eggplant (r = 0.27; P = 0.015) was positively correlated with the levels of lead. The correlation observed for cooked squash, eggs, pork and chicken meats, and chicken products was maintained after logistic regression adjustment. CONCLUSIONS: The presence of lead was detected in human colostrum in this sample, probably as a result of dietary exposure. In addition to a correlation between presence of lead and dietary intake, the present findings suggest that specific nutrients may result in increased or decreased levels of lead, without a direct relationship with socioeconomic factors.

Relação entre níveis de chumbo no colostro, consumo alimentar e características socioeconômicas de puérperas em Goiânia, Brasil / Relationship between lead levels in colostrum, dietary intake, and socioeconomic characteristics of puerperal women in Goiânia, Brazil

OBJETIVO: Estimar a concentração de chumbo em colostro humano e verificar a existência de relação entre esse dado, consumo alimentar e fatores socioeconômicos das puérperas. MÉTODOS: Estudo transversal com 80 puérperas de uma maternidade de Goiânia, Brasil, realizado de julho a dezembro de 2008. Aplicou-se um questionário socioeconômico e de estilo de vida, além do questionário de frequência de consumo alimentar. Posteriormente, foram coletadas amostras de colostro, analisadas por espectrometria de absorção atômica por chama para quantificar o chumbo. Calculou-se a correlação entre o teor de chumbo, as variáveis socioeconômicas e o consumo alimentar. RESULTADOS: A média da concentração de chumbo foi 6,88 μg/L, e a mediana foi 4,65 μg/L. Os aspectos socioeconômicos não apresentaram associação significativa com o teor de chumbo. A ingestão de ácidos graxos saturados, ovos, carnes suínas, frango e derivados (todos com valores de r = -0,26 e P = 0,020) correlacionou-se inversamente ao teor chumbo do colostro humano, ao passo que a ingestão de abóbora (r = 0,26 e P = 0,019) e berinjela (r = 0,27 e P = 0,015) correlacionou-se proporcionalmente ao valor obtido. A correlação entre abóbora cozida, ovos, carnes suínas, de frango e derivados foi mantida após ajuste na regressão logística. CONCLUSÕES: Foi detectada presença de chumbo no colostro materno, possivelmente como resultado da exposição dietética das puérperas deste estudo. Além da correlação entre presença de chumbo e consumo alimentar, os resultados sugerem que a ingestão de nutrientes específicos pode propiciar maior ou menor concentração desse contaminante, sem relação direta com fatores socioeconômicos.

OBJECTIVE: To estimate the levels of lead in human colostrum and investigate whether they are correlated with dietary intake and socioeconomic factors in puerperal women. METHOD: This cross-sectional study was carried out with 80 puerperal women from a maternity hospital in Goiânia, Brazil. Data were collected between July and December 2008. A questionnaire was used to collect socioeconomic and lifestyle information. A dietary intake frequency questionnaire was also applied. After that, colostrum samples were collected and analyzed using flame atomic absorption spectrometry to quantify lead levels. The correlation between lead levels, socioeconomic variables, and dietary intake was calculated. RESULTS: The mean concentration of lead in colostrum samples was 6.88 μg/L, and the median concentration was 4.65 μg/L. There was no association between socioeconomic aspects and lead levels. The intake of saturated fatty acids, eggs, pork meats, chicken, and chicken products (r = -0.26 and P = 0.020) was inversely correlated with the levels of lead in human colostrum, whereas the intake of squash (r = 0.26; P = 0.019) and eggplant (r = 0.27; P = 0.015) was positively correlated with the levels of lead. The correlation observed for cooked squash, eggs, pork and chicken meats, and chicken products was maintained after logistic regression adjustment. CONCLUSIONS: The presence of lead was detected in human colostrum in this sample, probably as a result of dietary exposure. In addition to a correlation between presence of lead and dietary intake, the present findings suggest that specific nutrients may result in increased or decreased levels of lead, without a direct relationship with socioeconomic factors.

[Cadmium in human milk: concentration and relation with the lifestyle of women in the puerperium period]. / Cádmio no leite materno: concentração e relação com o estilo de vida da puérpera.

PURPOSE: To relate the cadmium concentration of colostrum with the lifestyle of women in the puerperium period. METHODS: A cross-sectional study was conducted in Goiânia, Goiás (Mid-western Region of Brazil). Eighty women, according to inclusion criteria, were interviewed about their socioeconomic characteristics and lifestyle. They answered a questionnaire about food frequency consumption (FFQ). The colostrum samples collected were analyzed by flame atomic absorption spectrometry to quantify cadmium levels. For statistical analysis, central tendency measures were obtained, and the Mann-Whitney and Kruskal-Wallis tests were performed, as well as correlation and regression tests. RESULTS: The average cadmium concentration was 2.3 µg/L and the median was 0.9 µg/L. Variables such as age and parity showed a nonsignificant positive correlation with cadmium. Smoking habit was not significantly associated with cadmium. CONCLUSIONS: Postpartum food intake influences the level of cadmium in colostrum, especially vegetables such as cereals.