Anaemia affects more than 36 % of all pregnancies globally and is associated with significant maternal and neonatal morbidity and mortality. Iron deficiency is widely recognised as the most common nutritional cause of anaemia but other nutrient deficiencies are also implicated, including the B vitamin riboflavin, albeit its role is largely under-investigated and thus typically overlooked. Riboflavin, in its co-factor forms flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), is required for numerous oxidation-reduction reactions, antioxidant function and in the metabolism of other B vitamins and iron. While clinical deficiency of riboflavin is largely confined to low-income countries, sub-clinical (functional) deficiency is much more widespread, including in high-income countries, and is particularly common among women of reproductive age and during pregnancy. Limited observational evidence from high-income populations suggests that suboptimal riboflavin status contributes to an increased risk of anaemia. Furthermore, randomised controlled trials in pregnant women from low- and middle-income countries have demonstrated beneficial effects of riboflavin on haematological status and anaemia. Various mechanisms have been proposed to explain the contribution of riboflavin deficiency to anaemia, with the strongest evidence pointing to an adverse effect on iron metabolism, given that riboflavin co-factors are required for the release of iron from storage ferritin in the production of red blood cells. Overall, this review investigates riboflavin intakes and status during pregnancy in different populations and evaluates the available evidence for the under-recognised role of riboflavin in the maintenance of haemoglobin concentrations together with its potential to protect against the development of anaemia during pregnancy.

Even though antiretroviral therapy (ART) access for human immunodeficiency virus (HIV)-infected children increased dramatically, anaemia has continued as a challenge regardless of a cluster of differentiation (CD4) count and viral load. Hence, the present study aimed to assess the determinants of iron deficiency anaemia among children living with HIV after the initiation of ART. An institution-based unmatched case–control study was conducted among consecutively selected 712 children on HIV care from 1 September to 30 October 2022 in the Metekel zone. A pre-tested and structured data extraction checklist was used to collect the data. Data were analysed using STATA version 16 software. Binary logistic regression was used to find the association between independent variables and anaemia. The level of statistical significance was declared at a value of P < 0⋅05. A total of 712 HIV-positive children (178 cases and 534 controls) were included in this study, with a completeness rate of 98⋅8 %. In multivariable analysis, variables that have a statistically significant association with anaemia were as follows: CD4 count <350 (Adjusted Odds Ratio [AOR] 2⋅76; 95 % CI 1⋅76, 4⋅34), World Health Organization (WHO) clinical stage III (AOR 7⋅9; 95 % CI 3⋅5, 17⋅91) and stage IV (AOR 7⋅8; 95 % CI 3⋅37, 18⋅1), cotrimoxazole prophylaxis therapy (AOR 0⋅5; 95 % CI 0⋅31, 0⋅8) and mid-upper arm circumference (MUAC) ≤11⋅5 mm (AOR 2⋅1; 95 % CI 1⋅34, 3⋅28). The present study found that CD4 count, WHO clinical stage, cotrimoxazole prophylaxis therapy and MUAC were significantly associated with anaemia in children on ART. Therefore, continuous screening of anaemia and nutritional treatment is essential in these patients.

Anaemia remains among the most prevalent nutritional problems among children in developing countries. In Ethiopia, more than half of children <5 years of age are anaemic. In the early stages of life, it leads to poor cognitive performance, delay psychomotor development and decreases working capacity in later life. The present study aimed to assess the prevalence and associated factors of anaemia among children aged 6–23 months in the Bale zone. A community-based cross-sectional study was conducted from 1 to 30 June 2021. Multistage stratified sampling and simple random sampling techniques were employed to select 770 samples. An interviewer-administered questionnaire was used to collect data on socio-demographic, child health and feeding practices. Haemoglobin levels were estimated using a portable Hemosmart machine. Children with haemoglobin values below 11 g/dl were considered anaemic. Binary logistic regression analysis was performed to identify factors associated with anaemia. Statistical significance was set at P < 0⋅05. The prevalence of anaemia was 47⋅9 % (95 % CI (44⋅4, 51⋅5)). The multivariate analysis showed that child age (6–11 months) (AOR 1⋅47; 95 % CI (1⋅06, 2⋅03)), household food insecurity (AOR 1⋅44; 95 % CI (1⋅01, 2⋅04)), having diarrhoea and cough in the past 2 weeks (AOR 1⋅70; 95 % CI (1⋅18, 2⋅44)) and (AOR 1⋅97; 95 % CI (1⋅28, 3⋅04), respectively), not consuming the recommended dietary diversity (AOR 2⋅72; 95 % CI (1⋅96, 3⋅77)) and stunting (AOR 1⋅88; 95 % CI (1⋅31, 2⋅70)) were significantly associated with anaemia. Anaemia in children aged 6–23 months was a severe public health problem in the study area. Integrated nutritional interventions combined with iron fortification and supplementation is recommended.

Ethiopia recently scaled up the implementation of a school feeding program (SFP) as a targeted intervention for protecting disadvantaged school children from hunger and food insecurity. However, the contribution of the program to advancing the nutritional status of children has not been adequately explored. We assessed the effect of SFP on the anthropometric and haemoglobin status of school children in Sidama Region, Southern Ethiopia. Our prospective cohort study compared the height-for-age z-score (HAZ), BMI-for-age z-score (BAZ) and haemoglobin concentration of SFP beneficiary (n 240) and non-beneficiary (n 240) children, 10–14 years of age. The children were recruited from 8 SFP implementing and 8 control schools using a multistage sampling procedure and were followed for an academic year. The SFP intervention and control schools were matched one-to-one based on agro ecological features and geographical proximity. Exposure, outcome and pertinent extraneous variables were collected through baseline and end-line surveys. Multilevel difference-in-differences (DID) analysis was used to measure the net effect on the outcomes of interest. In the multivariable DID model adjusted for potential confounders including maternal and paternal literacy, household monthly income, wealth index and household food insecurity, the SFP did not show significant effects on the haemoglobin concentration (β = 0⋅251, 95 % confidence interval (CI): −0⋅238, 0⋅739), BAZ (β = 0⋅121, 95 % CI: −0⋅163, 0⋅405) and HAZ (β = −0⋅291, 95 % CI: −0⋅640, 0⋅588) of children.

We studied ethnic differences in terms of iron status during pregnancy between Dutch women and other ethnicities and explore to what extent these differences can be explained by environmental factors. This cross-sectional population-based study (2002–2006) was embedded in the Generation R study and included a total of 4737 pregnant women from seven ethnic groups (Dutch, Turkish, Moroccan, Cape Verdean, Surinamese-Hindustani, Surinamese-Creole and Antillean). Ethnicity was defined according to the Dutch classification of ethnic background. Ferritin, iron and transferrin were measured in early pregnancy. The overall prevalence of iron deficiency was 7 %, ranging from 4 % in both Dutch and Surinamese-Creoles, to 18 % in Turkish, Moroccan and Surinamese-Hindustani women. Iron overload was most prevalent in Surinamese-Creole (11 %) and Dutch (9 %) women. Socioeconomic factors accounted for 5–36 % of the differences. Income was the strongest socioeconomic factor in the Cape Verdean and Surinamese-Hindustani groups and parity for the Turkish and Moroccan groups. Lifestyle determinants accounted for 8–14 % of the differences. In all groups, the strongest lifestyle factor was folic acid use, being associated with higher iron status. In conclusion, in our population, both iron deficiency and iron overload were common in early pregnancy. Our data suggest that ethnic differences in terms of socioeconomic and lifestyle factors only partly drive the large ethnic differences in iron status. Our data support the development of more specific prevention programmes based on further exploration of socioeconomic inequities, modifiable risk and genetic factors in specific ethnic subgroups, as well as the need for individual screening of iron status before supplementation.

Deer mice (Peromyscus maniculatus) are hosts to ixodid ticks as well as the associated tick-borne pathogens they can spread. As the ranges of black-legged ticks (Ixodes scapularis) and American dog ticks (Dermacentor variabilis) expand northwards, naïve host populations of deer mice are likely to become infested by ticks and experience the physiological effects that ticks can have on them via blood-feeding. The prevalence of these haematophagous ticks can affect the haemoglobin levels of the mice they infest. Haemoglobin levels were compared and analysed in deer mice populations at three different sites with varying tick exposure. These results suggested that without confounding effects, the abundance of black-legged and American dog ticks on individual mice had a significant negative effect on the hosts' haemoglobin levels, but only in an area with high tick infestation. This was seen across the average haemoglobin levels between populations, where there was a significant difference between the source population with the longest established tick populations and the source population where neither black-legged nor American dog ticks were prevalent. As the ticks' ranges expand and they become more abundant, it is important to understand how their prevalence and intensity can alter host physiology, potentially affecting their own range expansion and the spread of the diseases they may carry.

Undernutrition is a major global health problem. Various types of animal milk are used for feeding children at early ages; however, associations of camel milk (CaM) and bovine milk (BM) with the nutritional status of children have not been explored. A comparative community-based cross-sectional study was conducted among pre-schoolers in rural pastoral districts of Somali, Ethiopia. Children were selected from households with lactating camels or cows. Anthropometric measurements followed standard procedures for height-for-age, weight-for-age and weight-for-height scores. Independent sample t-tests identified significant differences in anthropometric indices based on the type of milk consumed. Multivariable logistic regression was used to examine associations between milk consumption and other predictors of growth failures. The prevalence of stunting was 24⋅1 % [95 % confidence interval (CI) 20⋅5, 28⋅3] of pre-schoolers, 34⋅8 % (95 % CI 29⋅9, 39⋅6) were wasted and 34⋅7 % (95 % CI 30⋅1, 39⋅9) were underweight. Higher proportions of BM-fed children were severely stunted, wasted and underweight compared with CaM consumers. Using logistic regression models, children who consumed BM [adjusted odds ratio (AOR): 2⋅10; 95 % CI 1⋅22, 3⋅61] and who were anaemic (AOR: 4⋅22; 95 % CI 2⋅23, 7⋅98) were more likely to be stunted than their counterparts, while girls were less likely to be stunted than boys (AOR: 0⋅57; 95 % CI 0⋅34, 0⋅94). Similarly, children who consumed BM (AOR: 1⋅97; 95 % CI 1⋅20, 3⋅24), who were anaemic (AOR: 2⋅27; 95 % CI 1⋅38, 3⋅72) and who drank unsafe water (AOR: 1⋅91; 95 % CI 1⋅19, 3⋅07) were more likely to be underweight than their counterparts. In conclusion, CaM consumption was associated with lower prevalence of stunting and underweight than BM. Promoting CaM in pastoralist areas may help to curb the high level of undernutrition.

Genetic parameters were estimated for haemoglobin (Hb) levels in sows and piglets as well as sow reproductive performance and piglet survival. Reproductive traits were available between 2005 and 2014 for 7857 litters from 1029 Large White and 858 Landrace sows. In 2012 and 2013, Hb levels, sow BW and sow back fat depth were measured on 348 sows with 529 litters 5 days prior to farrowing. In addition, Hb levels were available for 1127 one-day-old piglets from 383 litters (a maximum of three piglets per litter) of 277 sows with Hb levels. The average Hb levels in sows (sow Hb), their litters (litter Hb, based on average Hb of three piglets) and individual piglets (piglet Hb) were 112 ± 12.6 g/l, 103 ± 15.3 g/l and 105 ± 21.7 g/l, respectively. Heritabilities for Hb levels were 0.09 ± 0.07 for sow Hb, 0.19 ± 0.11 for litter Hb and 0.08 ± 0.05 for piglet Hb. Estimates for the permanent environment effect of sows were 0.09 ± 0.09 for sow Hb, 0.11 ± 0.12 for litter Hb and 0.12 ± 0.03 for piglet Hb. In comparison, heritabilities for both number of stillborn piglets and pre-weaning survival were lower (0.05 ± 0.01 and 0.04 ± 0.01). Sow BW had no significant heritability, while sow back fat depth was lowly heritable (0.10 ± 0.08). Positive genetic correlations were found between sow Hb and litter Hb (0.64 ± 0.47) and between litter Hb and sow back fat depth (0.71 ± 0.53). Higher litter Hb was genetically associated with lower number of stillborn piglets (−0.78 ± 0.35) and higher pre-weaning survival (0.28 ± 0.33). Negative genetic correlations between sow Hb and average piglet birth weight of the litter (−0.60 ± 0.34) and between piglet Hb and birth weight of individual piglets (−0.37 ± 0.32) indicate that selection for heavier piglets may reduce Hb levels in sows and piglets. Similarly, selection for larger litter size will reduce average piglet birth weight (rg: −0.40 ± 0.12) and pre-weaning survival (−0.57 ± 0.13) and may lead to lower litter Hb (−0.48 ± 0.27). This study shows promising first results for the use of Hb levels as a selection criterion in pig breeding programs, and selection for higher Hb levels may improve piglet survival and limit further reduction in Hb levels in sows and piglets due to selection for larger and heavier litters.

Strategies for preventing Fe deficiency include Fe supplementation and Fe fortification of foods. The absorption, metabolism and chemical characteristics of Fe multi-amino acid chelate (IMAAC) are not known. Absorption of IMAAC was compared with FeSO4 in Fe-depleted mice and in vitro chemical studies of the Fe supplement was performed in HuTu 80 cells. Hb repletion study was carried out in Fe-deficient CD1 mice that were fed for 10 d a diet supplemented with ferrous IMAAC or FeSO4. A control group of Fe-replete mice was fed a diet with adequate Fe concentrations throughout the study. Tissues were collected from the mice, and the expression of Fe-related genes was determined by quantitative PCR. Ferric reductase and Fe uptake were evaluated in HuTu 80 cells. Supplementation of the diet with FeSO4 or IMAAC significantly increased Hb levels (P<0·001) in Fe-deficient mice from initial 93·9 (SD 10·8) or 116·2 (SD 9·1) to 191 (SD 0·7) or 200 (SD 0·5) g/l, respectively. Initial and final Hb for the Fe-deficient control group were 87·4 (SD 6·7) and 111 (SD 11·7) g/l, respectively. Furthermore, the liver non-haem Fe of both supplement groups increased significantly (P<0·001). IMAAC was more effective at restoring Fe in the spleen compared with FeSO4 (P<0·005). Gene expression showed the IMAAC supplement absorption is regulated by the body’s Fe status as it significantly up-regulated hepcidin (P<0·001) and down-regulated duodenal cytochrome b mRNA (P<0·005), similar to the effects seen with FeSO4. A significant proportion of Fe in IMAAC is reduced by ascorbic acid. Fe absorption in mice and cells was similar for both IMAAC and FeSO4 and both compounds induce and regulate Fe metabolism genes similarly in the maintenance of homeostasis in mice.

Gastrothylax crumenifer haemoglobin was isolated, purified, chromatographed, and its molecular weight determined on a calibrated Sephadex G–100 column as well as by sodium dodecyl sulphate by the former and 16 500 by the latter method. The oxygen affinity of the pigment (P50O2) was found to be 6·1 mm Hg at pH 7·4.

A comparative studs of the spectral, electrophoretic and isoelectric properties of the haemoglobins of three trematodes. Paramphistomum epiclitum. Gigantocotyle explanatum and Gastrothylax erumenifer was carried out. A high absorption in the beta band region indicates that trematode haemoglobins have high oxygen affinities. Electrophoretic mobilities of all trematode and their host haemoglobins were different. The isoelectric points of trematode haemoglobins were found to focus in the acidic range except that of G. crumenifer haemoglobin I. which focused at an alkaline pH.

A haemoprotein released in vitro by adult Fasciola hepatica was purified by gel filtration chromatography on Sephacryl S-200 and ion-exchange chromatography on DEAE-Sepharose. The molecule, with an apparent molecular weight of > 200 kDa, contains a haem group and has absorption spectra characteristics similar to haemoglobins. N-terminal amino acid sequence analysis revealed no similarity between the F. hepatica haemoglobin and other vertebrate or invertebrate haemoglobins. Antibodies to the haemoglobin molecule can be detected in the sera of F. hepatica-infected bovines as early as 1 week after infection.

Intraerythrocytic malaria parasites ingest the cytosol of their host cell and digest it inside their acid food vacuoles. Acidified (pH 4–5·5, 37 °C) human red blood cell lysates were used to simulate this process, measuring the denaturation of haemoglobin (Hb) and the release of iron, in the absence or presence of exogenous protease. Spontaneous Hb denaturation and appearance of non-heme iron were observed upon lysate acidification, their rates decreasing with increasing pH, and increasing in the presence of protease. Both processes were inhibited by the quinoline-containing anti-malarial drugs (QCDs) chloroquine, quinine, mefloquine and amodiaquine at concentrations well below those expected in the acidic food vacuole of the parasite. Spectrophotometric analysis indicated that chloroquine complexes with heme in acid-denatured haemoglobin. Other weak bases as well as verapamil and diltiazem, known to reverse the resistance of malarial parasites to chloroquine, were without efifect indicating that the action of QCDs is specific. Based on our previous results and the present report, we suggest that iron release in acidified lysates is mediated through the formation of ferryl (Fe(IV)) radicals. QCDs possibly complex with this radical, as they do with heme, and prevent its contact with an adjacent heme molecule which is required for ring opening and iron release. These results may suggest that one of the anti-malarial effects of QCDs is to deprive the parasite of an adequate iron supply. Addition of iron to cultures of Plasmodium falciparum was expected to circumvent the deprivation of iron and reduce the anti-malarial eflfect of QCDs. However, adding iron as penetrating fructose or nitrilotriacetate complexes did not alter the parasite's susceptibility to chloroquine. Ascorbate markedly increased the release of iron in acidified lysates, and this effect was not reduced by chloroquine. Ascorbate was found to decrease parasite susceptibility to chloroquine, suggesting that iron deprivation may be an important factor in the anti-malarial action of QCDs.

Western blot analysis using an anti-globin rabbit serum Rb94 revealed a major band of 17 kDa in extracts of Ostertagia ostertagi adults and 4th-stage larvae. The adult stage globin-like antigen (OoAdGlb) was purified from total worm extracts by liquid chromatography. The protein has an estimated molecular mass of 36 kDa under non-reducing conditions, suggesting a dimeric structure containing 2 non-covalently linked 17 kDa monomers. Tryptic peptides were sequenced and showed strong similarities with the globins of free-living and parasitic nematodes. Immunolocalization revealed the presence of this globin-like antigen in the body wall musculature and/or the cuticle of O. ostertagi adults. An enzyme-linked immunosorbent assay based on the purified OoAdGlb showed no differences in response between calves infected by O. ostertagi and/or Cooperia oncophora and the negative controls.