Thermosensitive Chitosan Hydrogels: A Potential Strategy for Prolonged Iron Dextran Parenteral Supplementation

Iron deficiency anemia (IDA) presents a global health challenge, impacting crucial development stages in humans and other mammals. Pigs, having physiological and metabolic similarities with humans, are a valuable model for studying and preventing anemia. Commonly, a commercial iron dextran formulation (CIDF) with iron dextran particles (IDPs) is intramuscularly administered for IDA prevention in pigs, yet its rapid metabolism limits preventive efficacy. This study aimed to develop and evaluate chitosan thermosensitive hydrogels (CTHs) as a novel parenteral iron supplementation strategy, promoting IDPs' prolonged release and mitigating their rapid metabolism. These CTHs, loaded with IDPs (0.1, 0.2, and 0.4 g of theoretical iron/g of chitosan), were characterized for IM iron supplementation. Exhibiting thermosensitivity, these formulations facilitated IM injection at ~4 °C, and its significant increasing viscosity at 25-37 °C physically entrapped the IDPs within the chitosan's hydrophobic gel without chemical bonding. In vitro studies showed CIDF released all the iron in 6 h, while CTH0.4 had a 40% release in 72 h, mainly through Fickian diffusion. The controlled release of CTHs was attributed to the physical entrapment of IDPs within the CTHs' gel, which acts as a diffusion barrier. CTHs would be an effective hydrogel prototype for prolonged-release parenteral iron supplementation.

Effects of dietary supplement with a Chinese herbal mixture on growth performance, antioxidant capacity, and gut microbiota in weaned pigs

Weaning stress decreases the growth performance of piglets and is one of the main concerns of pig industries. Traditional Chinese herbal medicines have been used to reduce the adverse effects of weaning stress as both nutritional supplements and antibiotic substitutes. This study aimed to evaluate the effects of a Chinese herbal mixture (Kangtaile, which contained Paeonia lactiflora, licorice, dandelion, and tea polyphenols) on the growth performances, immune response, antioxidant capacity, and intestinal microbiota of weaned pigs. A total of 400 weaned pigs [Duroc × (Landrace × Yorkshire)] were randomly allocated into one of four treatments: the CON group, fed with basic diet; the HM1 group, fed with basal diet supplemented with 0.5 g herbal mixture/kg diet; the HM2 group, fed with basal diet supplemented with 1.0 g herbal mixture/kg diet; or the HM3 group, fed with basal diet supplemented with 1.5 g herbal mixture/kg diet. The results revealed that dietary supplementation with the herbal mixture for 28 days improved average daily gain and feed conversion ratio, while decreased the diarrhea rate of weaned pigs. Moreover, dietary supple-mentation with the herbal mixture improved the antioxidant capacity through increasing the activity of catalase (CAT) and the total antioxidant capacity (T-AOC) level, while decreasing the concentration of malondialdehyde (MDA) in the serum. Pigs supplemented with herbal mixture presented an increased serum immunoglobulin (Ig)M level on day 14 compared with control pigs. The herbal mixture altered the composition of intestinal microbiota by influencing the relative abundances of Firmicutes and Bacteroidetes at the phylum level. The relative abundances of the Firmicutes and Bacteroidetes were significantly related to the body weight gain of pigs. In conclusion, supplementation of herbal mixture to the diet improved growth performance, immunity, and antioxidant capacity and modified the composition of intestinal microbiota in weaning pigs. This study provided new insights into the nutritional regulation effects of the herbal mixtures on weaned pigs.

Novel edible toys as iron carrier to prevent iron deficiency of postweaned pigs

The current preventive treatment for iron deficiency in pigs is inefficient, resulting in a high prevalence of iron-deficient or anemic postweaned pigs. The aim of this study was to develop and characterize edible toys (ETs) to be used as oral iron supplements, and to assess their effect on feeding behavior and iron status of postweaned pigs. Three types of ETs, varying in sweetness, were produced by ionic gelation, using whey, sodium alginate, ferrous sulfate and atomized bovine erythrocytes. ET control (ETC) was developed without sweetener, ET1 contained 15% w/v sucrose and ET2 contained 0.03% w/v of Sucram (98% sodium saccharin, 1% neosperidine dihydrocalcone and 1% maltol). ETs were mainly composed of carbohydrates and protein, with a similar concentration of iron (2.2-2.7 mg/g). The ETs were offered to 24 postweaned pigs to measure acceptability and preference. The animals preferred ETC and ET2 over ET1. To assess the nutritional benefit of the ETs, 24 postweaned pigs were distributed into three groups: ETC (without iron), ETC-Fe (ETC with iron) and ET2-Fe (with iron and Sucram). Iron-loaded ET (ETC-Fe and ET2-Fe) significantly increased the concentration of red blood cells (from 6.1 to 7.5·10⁶ x mm³ for ETC-Fe and from 6.2 to 7.8 for ET2-Fe), hematocrit (from 32.8 to 37.9% for ETC-Fe and from 32.3 to 35.1 for ET2-Fe), serum iron (from 28.6 to 120.6 µmol/L for ETC-Fe and from 34.9 to 145.4 for ET2-Fe) and serum ferritin (from 7.8 to 18.5 µg/L for ETC-Fe and from 8.1 to 20.2 for ET2-Fe). In conclusion, the ETs developed in this study were accepted by the pigs and provided adequate iron to improve the iron status of postweaned pigs.

Exploratory Study: Excessive Iron Supplementation Reduces Zinc Content in Pork without Affecting Iron and Copper

Simple Summary

Currently, all pigs raised on intensive farms develop iron-deficiency anemia if they do not receive supplemental iron at birth. Weaning diets commonly contain high concentrations of iron, and the effect on the copper and zinc contents in pork is unknown. In this exploratory work, we determined the effect of excessive oral iron supplementation on the contents of these microminerals in pork. Surprisingly, we found that high iron doses of 3000 ppm reduced the zinc content of pork by 32–55%.

Abstract

The aim of this work was to determine in an exploratory manner the effect of excessive iron supplementation on iron, zinc, and copper contents in pork and pork offal. Pigs averaging 50 days in age and 15 ± 1.3 kg body weight were allocated to a control group (500 ppm dietary Fe) and a supplemental group (3000 ppm dietary Fe). After an iron supplementation period of 60 days, blood samples were analyzed to determine iron biomarkers, serum copper, and zinc contents. Animals were slaughtered to assess total iron, non-heme iron, heme iron, zinc, and copper contents in samples of nine meat cuts and some offal. Iron supplementation improved the iron status in pigs with increased hemoglobin and hematocrit, but did not affect serum levels of iron, zinc, and copper. Iron supplementation did not affect the heme and non-heme iron contents of the different meat cuts. Zinc contents decreased by 32–55% in meat cuts, where iron content increased in the liver, spleen, kidneys, and pancreas. No differences of zinc and copper were observed in offal samples. High concentrations of iron supplementation reduce zinc content in pork.

Peroral iron supplementation can be provided to piglets through a milk cup system with results comparable to parenteral iron administration

The objective of this study was to investigate if iron can be allocated to piglets through sow milk replacer fed in a milk cup system with efficacies comparable to intramuscular (IM) administration of 200 mg gleptoferron. Two hundred and ninety-four piglets from 21 litters were allocated to three different iron treatments (n = 98). The treatments were 1) Control (CON) provided no supplemental iron, 2) Injected iron (II) provided 200 mg gleptoferron IM on day 3 postpartum, and 3) Milk iron (MI) provided sow milk replacer “DanMilk Supreme” added 1 % “Piglet Boozt” ad libitum from day 0 until 21 days postpartum. All piglets had access to dry feed from day 6. Initial and final body weight was registered and hemoglobin (Hb) levels were analyzed on day 0, 3, 7, 10, 17, and 21 after farrowing. In order to correlate drinking pattern with Hb level and growth, video cameras were installed, and drinking pattern was recorded on day 18 postpartum. A blood sample was drawn from piglets from three litters per treatment on day 21 for a complete hematology profile. The results showed that iron treatment had an effect on Hb levels (P < 0.001) that were different between all groups from day 10, resulting in a mean Hb level of 76.2 g/L (CON), 120.9 g/L (II), and 105.4 g/L (MI) on day 21. The mean Hb level for both MI and II was above the anemia threshold of 90 g/L and the Hb level of the II group was above 110 g/L and the piglets thus defined as normal. Treatment had a significant effect on Hb, hematocrit (hct), mean corposcular volume (MCV), mean corpuscular hemoglobin (MCH), red blood cell distribution width (RDW), lymphocytes (%), neutrophils (bill/L) (P < 0.05), neutrophils (%) (P < 0.01), with CON being significantly different from MI and II that were similar or tended to differ. Total visits at the cup was not correlated to Hb level (r = 0.08) and growth was not affected by treatment (P = 0.99). It is concluded that iron can be supplemented to piglets through a milk cup system with efficacies comparable to parenteral administration of 200 mg gleptoferron.

Long-term Effect of Split Iron Dextran/Hemoglobin Supplementation on Erythrocyte and Iron Status, Growth Performance, Carcass Parameters, and Meat Quality of Polish Large White and 990 Line Pigs

Heme is an efficient dietary iron supplement applied in humans and animals to prevent iron deficiency anemia (IDA). We have recently reported that the use of bovine hemoglobin as a dietary source of heme iron efficiently counteracts the development of IDA in young piglets, which is the common problem in pig industry. Here, we used maternal Polish Large White and terminal sire breed (L990) pigs differing in traits for meat production to evaluate the long-term effect of split supplementation with intramuscularly administered small amount of iron dextran and orally given hemoglobin on hematological indices, iron status, growth performance, slaughter traits, and meat quality at the end of fattening. Results of our study show that in pigs of both breeds split supplementation was effective in maintaining physiological values of RBC and blood plasma iron parameters as well as growth performance, carcass parameters, and meat quality traits. Our results prove the effectiveness of split iron supplementation of piglets in a far-reach perspective.

Use of Encapsulation Technology to Improve the Efficiency of an Iron Oral Supplement to Prevent Anemia in Suckling Pigs

Simple Summary

In animal nutrition, encapsulation technologies have been poorly explored, even though they may improve oral iron supplementation in suckling pigs. We hypothesized that the encapsulation of an oral supplement could enhance iron bioavailability for suckling pigs. We compared the levels of biomarkers for iron nutritional status among three groups of animals: piglets receiving oral encapsulated supplements, individuals receiving oral non-encapsulated supplements (as control group), and animals who were supplemented by parenteral route (strategy currently used in pig production systems). All treatments prevented anemia at weaning; however, only oral treatments prevented the first stage of anemia, which is iron depletion. In conclusion, piglets supplemented with encapsulated iron showed a higher concentration of serum ferritin and, therefore, had better iron reserves.

Abstract

The objective of this study was to develop an encapsulated iron supplement for oral ingestion and to determine its effect on the iron nutrition status of suckling pigs. Encapsulated and non-encapsulated iron supplement was prepared. Seventy-two neonatal piglets were assigned to three experimental groups: (1) parenteral group (gold standard treatment), which received one dose of parenteral iron (200 mg), 2 days of age, (2) “non-encapsulated” group (as a control group), which received 4 oral doses of unencapsulated iron supplement at 2, 7, 12 and 17 days of age, and (3) “encapsulated” group, which received 4 oral doses of encapsulated iron supplement on the same days. The encapsulated and unencapsulated iron supplements contained 65.2 and 65.0 mg/iron/dose, respectively. Parenteral treatment was not sufficient to ensure an adequate iron nutritional state in piglets at the end of the lactation period, showing iron depletion (serum ferritin: 8.4 µg/L). In contrast, oral supplementation prevented the development of iron depletion. Higher serum ferritin values were observed in the encapsulated (19.9 µg/L) compared to the unencapsulated group (17.4 µg/L) (p = 0.020). In conclusion, the use of four oral doses of an encapsulated iron supplement prevents iron deficiency anemia and its previous stages in suckling pigs.

Iron Supplementation in Suckling Piglets: An Ostensibly Easy Therapy of Neonatal Iron Deficiency Anemia

In pigs, iron deficiency anemia (IDA) is the most prevalent deficiency disorder during the early postnatal period, frequently developing into a serious illness. On the other hand, in humans, only low-birth-weight infants, including premature infants, are especially susceptible to developing IDA. In both human and pig neonates, the initial cause of IDA is low birth iron stores. In piglets this shortage of stored iron results mainly from genetic selection over the past few decades for large litter sizes and high birth weights. As a consequence, pregnant sows cannot provide a sufficient amount of iron to the increasing number of developing fetuses. Supplementation with iron is a common practice for the treatment of IDA in piglets. For decades, the preferred procedure for delivering iron supplements during early life stages has been through the intramuscular injection of a large amount of iron dextran. However, this relatively simple therapy, which in general, efficiently corrects IDA, may generate toxic effects, and by inducing hepcidin expression, may decrease bioavailability of supplemental iron. New iron supplements are considered herein with the aim to combine the improvement of hematological status, blunting of hepcidin expression, and minimizing the toxicity of the administered iron. We propose that iron-deficient piglets constitute a convenient animal model for performing pre-clinical studies with iron supplements.

Longitudinal Effects of Iron Deficiency Anemia and Subsequent Repletion on Blood Parameters and the Rate and Composition of Growth in Pigs

Iron deficiency is reported as the most common nutrient deficiency worldwide. Due to rapid growth, infants are at particular risk for developing iron deficiency, which can easily progress to iron deficiency anemia (IDA), if not treated. The aim of this study was to determine the lasting effects of an early-life iron deficiency after a period of dietary iron repletion. Forty-two intact male pigs were fed, ad libitum, either control (CONT, 21.3 mg Fe/L) or iron-deficient (ID 2.72 mg Fe/L) milk replacer from postnatal day (PND) 2 to 32 (phase 1). From PND 33 to 61 (phase 2), all pigs were transitioned onto a series of industry-standard, iron-adequate diets. Blood was collected weekly from PND 7 to 28, and again on PND 35 and 56, and tissues were collected at either PND 32 or PND 61. At the end of phase 1, ID pigs exhibited reduced hematocrit (Hct; p < 0.0001) and hemoglobin (Hb; p < 0.0001) compared with CONT pigs, but neither Hct (p = 0.5968) nor Hb (p = 0.6291) differed between treatment groups after dietary iron repletion at the end of phase 2. Body weight gain was reduced (p < 0.0001) 58% at PND 32 in ID pigs compared with CONT pigs during phase 1, and this effect remained significant at the end of phase 2 (p = 0.0001), with ID pigs weighing 34% less than CONT pigs at PND 61. Analysis of peripheral protein and messenger RNA (mRNA) gene expression biomarkers yielded inconclusive results, as would be expected based on previous biomarker analyses across multiple species. These findings suggest that early-life iron status negatively influences blood parameters and growth performance, with dietary iron repletion allowing for full recovery of hematological outcomes, but not growth performance.

Oral iron administration in suckling piglets – a review

Iron deficiency is presently a serious problem in suckling piglets on pig farms. The most often used method of anaemia prevention in piglets is parenteral administration of iron dextran. Oral iron represents an alternative to this method. The goal of this article is to review current knowledge on oral iron administration in suckling piglets. The substances that can be used for this purpose include iron dextran, iron salts, iron chelates, carbonyl iron, an iron polymaltose complex and iron microparticles. The different methods of oral iron administration in piglets are discussed.