Multicenter biomonitoring of polybrominated diphenyl ethers (PBDEs) in colostrum from China: Body burden profile and risk assessment.

Polybrominated diphenyl ethers (PBDEs) were listed in the Stockholm Convention due to their persistent and toxic nature. In utero exposure to PBDEs might affect fetal development as it is sensitive when exposed to even low dose of xenobiotic substances during the pregnancy. In this study, a multi-centre human biomonitoring study of tri-to hexa-BDEs was conducted in three Chinese cities using 60 colostrum samples from local residents. The patterns and influencing factors, correlation with the birth outcome, and potential health risks during the breastfeeding of tri-to hexa-BDEs in the colostrum samples were assessed. The median concentration of tri-to hexa-BDEs was 9.1 (Interquartile range: 3.1-19.5) ng g-1 lipid weight, and BDE-153 contributed 68% of the detected PBDEs. The PBDE levels were mostly associated with maternal age and drinking water sources, while correlations with other factors including weight gain, BMI, parity and the number of aborted pregnancies was not significant. The level of BDE-28 was positively correlated with the birth weight, while the BDE-99 was positively correlated with the head circumference, using multilinear regression. For the total hazard quotients, 60% of the infants have an estimated value higher than 1, showed potential chronic hazard for future development and possible adverse health effects to the babies from the exposure to PBDE congeners. Alternative food source seems to have a lower risk for neonates than the colostrum, but the advantages of breastfeeding undoubtedly outweigh the risks and potential adverse health effects caused by environmental PBDEs and other xenobiotic chemical exposure.

Upregulation of innate antiviral restricting factor expression in the cord blood and decidual tissue of HIV-infected mothers.

Programs for the prevention of mother-to-child transmission of HIV have reduced the transmission rate of perinatal HIV infection and have thereby increased the number of HIV-exposed uninfected (HEU) infants. Natural immunity to HIV-1 infection in both mothers and newborns needs to be further explored. In this study, we compared the expression of antiviral restricting factors in HIV-infected pregnant mothers treated with antiretroviral therapy (ART) in pregnancy (n=23) and in cord blood (CB) (n=16), placental tissues (n=10-13) and colostrum (n=5-6) samples and compared them to expression in samples from uninfected (UN) pregnant mothers (n=21). Mononuclear cells (MNCs) were prepared from maternal and CB samples following deliveries by cesarean section. Maternal (decidua) and fetal (chorionic villus) placental tissues were obtained, and colostrum was collected 24 h after delivery. The mRNA and protein expression levels of antiviral factors were then evaluated. We observed a significant increase in the mRNA expression levels of antiviral factors in MNCs from HIV-infected mothers and CB, including the apolipoprotein B mRNA-editing enzyme 3G (A3G), A3F, tripartite motif family-5α (TRIM-5α), TRIM-22, myxovirus resistance protein A (MxA), stimulator of interferon (IFN) genes (STING) and IFN-ß, compared with the levels detected in uninfected (UN) mother-CB pairs. Moreover, A3G transcript and protein levels and α-defensin transcript levels were decreased in the decidua of HIV-infected mothers. Decreased TRIM-5α protein levels in the villi and increased STING mRNA expression in both placental tissues were also observed in HIV-infected mothers compared with uninfected (UN) mothers. Additionally, colostrum cells from infected mothers showed increased tetherin and IFN-ß mRNA levels and CXCL9 protein levels. The data presented here indicate that antiviral restricting factor expression can be induced in utero in HIV-infected mothers. Future studies are warranted to determine whether this upregulation of antiviral factors during the perinatal period has a protective effect against HIV-1 infection.

Newborn calf vitality: risk factors, characteristics, assessment, resulting outcomes and strategies for improvement.

Dystocia is a stressful and traumatic event for both the cow and calf. As the prevalence of dystocia has increased over time, attention has been focused on maintaining the health and longevity of the cow. Lack of vitality in the newborn calf may go unnoticed and result in short or long-term implications for calf health and performance. A prolonged or assisted delivery may increase birth stress in calves causing a variety of effects including injury, inflammation, hypoxia, acidosis, pain and an inability to maintain homeostasis. Each of these effects can further contribute to a reduced state of vitality in the newborn calf. Newborn vitality is essential to the health, survival and welfare of the calf. If the calf is not vital at birth, it may be unwilling or unable to get up and suckle colostrum in a timely manner. Early colostrum intake improves passive transfer of immunoglobulins, energy uptake and thermoregulation. Intervention may be required to assist these calves such as respiratory and thermal support, manual feeding of colostrum or the administration of non-steroidal anti-inflammatory drugs to aid health and long-term survival. However, more research is needed to determine ways in which newborn calf vitality can be assessed and improved in order to reduce the increased risk of morbidity and mortality and long-term effects on performance.

Effects of continuous lactation and short dry periods on mammary function and animal health.

The dry period is required to facilitate cell turnover in the bovine mammary gland in order to optimize milk yield in the next lactation. Traditionally, an 8-week dry period has been a standard management practice for dairy cows based on retrospective analyses of milk yields following various dry period lengths. However, as milk production per cow has increased, transitioning cows from the nonlactating state to peak milk yield has grown more problematic. This has prompted new studies on dry period requirements for dairy cows. These studies indicate a clear parity effect on dry period requirement. First parity animals require a 60-day dry period, whereas lactations following later parities demonstrate no negative impact with 30-day dry period or even eliminating the dry period when somatotropin (ST) is also used to maintain milk yields. Shortened dry periods in first parity animals were associated with reduced mammary cell turnover during the dry period and early lactation and increased numbers of senescent cells and reduced functionality of lactating alveolar mammary cells postpartum. Use of ST and increased milking frequency postpartum reduced the impact of shortened dry periods. The majority of new intramammary infections occur during the dry period and persist into the following lactation. There is therefore the possibility of altering mastitis incidence by modifying or eliminating the dry period in older parity animals. As the composition of mammary secretions including immunoglobulins may be reduced when the dry period is reduced or eliminated, there is the possibility that the immune status of cows during the peripartum period is influenced by the length of the dry period.

Assessment of mammary gland metabolism in the sow. I. Development of methods for the measurement of cellular metabolites in milk and colostrum.

We have modified deproteinization methods and a number of spectrophotometric and bioluminescent methods in order to measure the concentrations of cellular metabolites in small volumes (< 0.3 ml) of sows' colostrum and milk. For the majority of the assays, recoveries ranged from 92 to 105%. The binding of ATP and UTP to a calcium phosphate-citrate-caseinate complex in milk, and the decrease in ATP (92%/h) and UTP (18.1%/h) concentrations during in vitro incubation of the whey fraction suggested that it was unlikely ATP and UTP (both < 1 microM) could exist free in sows' milk. The mean concentrations (range) of cellular metabolites in milk (6-11 d post partum) were: glucose, 669 microM (220-1367); glucose 6-phosphate, 63.0 microM (27.6-101.4); glucose 1-phosphate, 18.3 microM (13.1-24.8); UDPglucose, 296 microM (170-494); UDPgalactose, 635 microM (230-945); lactose, 162 mM (124-187); UDP, 105 microM (85-130); UMP, 1760 microM (1326-2587); inorganic phosphate, 13.5 mM (1.4-29.3); ATP, < 0.5 microM; ADP, 53.6 microM (10.5-171.25); AMP, 215 microM (61.6-491.6); cAMP, 22.3 microM (3.5-61.6); galactose, 198 microM (118-474) and fructose, 226 microM (172-283). Differences in the concentrations of glucose, glucose 6-phosphate, glucose 1-phosphate, UDPgalactose and cAMP between fore and hind milk samples indicated postsecretory changes in the concentrations of certain metabolites. Changes in the concentrations of metabolites during in vitro incubation of milk and of colostrum suggested that these postsecretory changes were probably due to the actions of enzymes present in mammary secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Lactoferrin levels and unsaturated iron-binding capacity in colostrum of Brazilian women of two socioecomic levels

The objetive of this study was to compare lactoferrin (LF) levels and unsaturated iron-binding capacity (UIBC) of colostrum from Brazilian women aged 20-38 years of low (N = 28) and high (N = 15) socioeconomic level. Both groups received a similar amount of supplental iron (25-65 mg/day) during pregnancy. We also determined the relationship between LF levels and UIBC, and between these components and maternal iron status. Both groups (low and high socieconomic level) showed adequate and similar mean hematocrit (35.0 ñ 13% and 35.9 ñ 1.3%, respectively) and serum ferritin (64 ñ 12 µg/1 and 57 ñ 12 µg/1, respectively) levels. Furthermore, LF levels (5.7 ñ 0.9 mg/ml and 5.5 ñ 0.6 mg/ml) and UIBC (3.8 ñ 0.3 µg/ml and 3/1 ñ 0.3 µg/ml) were not significantly different in the two groups of women, nor were they related to maternal hematocrit or serum ferritin. UIBC was significantly (P = 0.009), although weakly positively correlated (r= 0.45) with LF levels, suggesting that other colostrum ligands may contribute substantially to the capacity of colostrum to bind exogenous iron

Lactoferrin levels and unsaturated iron-binding capacity in colostrum of Brazilian women of two socioeconomic levels.

The objective of this study was to compare lactoferrin (LF) levels and unsaturated iron-binding capacity (UIBC) of colostrum from Brazilian women aged 20-38 years of low (N = 28) and high (N = 15) socioeconomic level. Both groups received a similar amount of supplemental iron (25-65 mg/day) during pregnancy. We also determined the relationship between LF levels and UIBC, and between these components and maternal iron status. Both groups (low and high socioeconomic level) showed adequate and similar mean hematocrit (35.0 +/- 1.3% and 35.9 +/- 1.3%, respectively) and serum ferritin (64 +/- 12 micrograms/l and 57 +/- 12 micrograms/l, respectively) levels. Furthermore, LF levels (5.7 +/- 0.9 mg/ml and 5.5 +/- 0.6 mg/ml) and UIBC (3.8 +/- 0.3 micrograms/ml and 3.1 +/- 0.3 micrograms/ml) were not significantly different in the two groups of women, nor were they related to maternal hematocrit or serum ferritin. UIBC was significantly (P = 0.009), although weakly positively correlated (r = 0.45) with LF levels, suggesting that other colostrum ligands may contribute substantially to the capacity of colostrum to bind exogenous iron.

Copper, zinc, and magnesium content of breast milk of Indian women.

Copper, zinc, and magnesium contents were determined in samples of breast milk obtained from 412 women in a low income group, from 100 women in a high income group of an urban population, and from 22 women from a low income group living in a rural area. Paired samples of milk and serum were collected from 152 women and the concentrations of copper and zinc in these two fluids were estimated. Copper levels fell from 0.46 microgram/ml in colostrum to 0.17 microgram/ml at 7 to 12 months of lactation; zince levels fell from 5.32 to 1.12 microgram/ml by 7 months. Magnesium level in colostrum was 40 micrograms/ml and reached a stable level of around 30 micrograms/ml in mature milk samples. Concentrations of copper and zinc in serum were not correlated with those in milk. Day to day and diurnal variations in the concentrations of these elements in milk were not significant indicating thereby that analysis of one sample provides satisfactory information of the trace element content in milk. There were no differences in the levels of these elements in milk between rural and urban low income groups of women. However significant differences were noted in the copper and zinc contents of milk of women from low and high income groups of the urban population, from the 1st to 3rd month of lactation.

Breast milk composition in Ethiopian and Swedish mothers. I. Vitamin A and beta-carotene.

The vitamin A and beta-carotene contents of breast milk were determined at different stages of lactation in three population groups: nonprivileged Ethiopian, privileged Ethiopian, and Swedish mothers. In addition, a fractionation of vitamin A giving the proportion of retinol was performed. The concentrations of retinol-binding protein (RBP) and (in part of the material) beta-carotene and prealbumin in plasma were also measured. The mean concentrations of vitamin A and beta-carotene in the milk from the Swedish mothers (period 0.5 to 6.5 months) were in the range of 40.0 to 53.1 and 16.3 to 20.8 mug/100 ml, respectively. For the privileged Ethiopian mothers (period 0.5 to 3.5 months) the corresponding ranges were 36.2 to 36.4 and 26.2 to 28.1 mug/100 ml and for the nonprivileged Ethiopian mothers (period 0.5 to 6.5 months) 28.1 to 33.1 and 23.9 to 25.6 mug/100 ml. Only the nonprivileged Ethiopian mothers were examined during a later stage of lactation (6.5 to 11.5 and 11.5 to 23.5 months). The concentrations of vitamin A and beta-carotene in their milk showed a downward trend. The proportion of retinyl ester (percentage of total vitamin A content) was significantly higher in the milk of Swedish mothers than in privileged and nonprivileged Ethiopian mothers. In the Swedish mothers retinol constituted 3.5% of the total vitamin A content of the milk; in Ethiopian mothers it was 15 to 30%. Determination of RBP in plasma showed normal values for Swedish mothers and lowered values for Ethiopian mothers--particularly the nonprivileged, in whom 14 of 81 values were below 20 mug/ml. RBP was demonstrated in colostrum, but only in a low concentration (in the order of 5 mug/ml).