One Iron Injection Is Not Enough—Iron Status and Growth of Suckling Piglets on an Organic Farm

Abstract

Simple SummarySuckling piglets need more iron for rapid and healthy growth than is available from sow’s milk alone. Therefore, iron supplementation is common on both conventional and organic farms and is usually carried out by a single injection of 200 mg iron during the piglets’ first days of life. However, the long suckling periods in organic pig farming can still lead to iron deficiency, as we found in a study with 288 piglets on an experimental farm. A single subcutaneous injection of iron led to lower iron levels and slower growth until weaning, when compared with giving iron two or three times. We conclude that one iron injection is not enough to ensure adequate iron supply and unimpaired growth of organically reared piglets, and options of additional iron supply need to be explored. AbstractSuckling piglets cannot satisfy their demand for the essential trace element iron from sows’ milk alone, which is poor in iron. Therefore, iron is usually supplemented by injecting 200 mg iron (as iron dextran) on day 3 post natum. However, the longer suckling period in organic pig herds leads to iron intake from feed starting later. We hypothesized that one iron injection is not enough for organically reared piglets, and that a second and third injection would improve their iron status and growth. On an organically certified experimental farm, 288 piglets from 32 litters were allocated to three treatments with one iron injection on day 3, two injections on day 3 and 14 and three injections on day 3, 14 and 21 post natum, respectively. One injection resulted in the lowest hematocrit and serum iron levels until day 28 post natum and the lowest daily weight gains until weaning, while piglets receiving two or three iron injections did not differ from each other. Based on these observations, we conclude that one iron injection is not enough to ensure adequate iron supply and unimpaired growth of organically reared piglets, and additional iron supply is necessary.

Effect of Additional Iron Injection to Suckling Pigs on Hematocrit Level during the Suckling Period

“…This indicates that the piglets could not meet their daily iron requirement over the suckling period and need an iron injection at birth. Furthermore, daily gain during suckling period increased from the first week to weaning [ 21 ] and hemoglobin and hematocrit decreased from d 17 to 21 of age after the iron injection at birth [ 6 , 17 ]. This supports the suggestion that an additional iron injection may be needed when they are weaned at older age over d 21 of age.…”

“…However, Friendship et al [ 3 ] reported that a single iron injection at d 4 of age was not sufficient to prevent iron deficiency at weaning ranged from 16 to 21 d. Perri et al [ 4 ] also reported that the traditional 200 mg of iron injection is insufficient to meet the needs for iron for the large and fast-growing piglets. As piglets grow fast during the suckling period and weaning weight increases with increasing weaning age up to d 28 of age, a single iron injection at birth may not be sufficient to prevent large piglets from anemia at weaning, which may result in growth retardation afterward [ 5 , 6 , 7 ]. However, Williams et al [ 8 ] reported that intramuscular injection of a 200 mg iron within 7 d after birth was sufficient to optimize pre- and postweaning growth performance of pigs.…”

“…Due to low absorption rate and less tissue retention of iron administered orally [ 10 , 11 ], an additional iron injection before weaning might be needed to improve hematological status and potentially growth of piglets [ 12 , 13 , 14 ] when the pigs are weaned at over 26–28 d of age although an additional iron injection could be laborious in the pig production [ 15 ]. Furthermore, it has not been demonstrated yet whether the effectiveness of additional iron injection depends on the hematological status of piglets at the administration that are dependent on the level of the first iron injection at birth [ 14 ] and the amount of iron additionally administered to piglets prior to weaning [ 6 ]. Therefore, the objective of the current study was to evaluate the effects of additional iron injection in suckling piglets when administered before weaning or with two levels of iron at birth on hematocrit levels during the suckling period as the hematocrit is a representative indicator of hematological status of pigs that is positively related to hemoglobin level and potential growth of piglets after weaning [ 16 ].…”

Pig Farming in Alternative Systems: Strengths and Challenges in Terms of Animal Welfare, Biosecurity, Animal Health and Pork Safety

“…Another study showed that supplemented piglets born outdoors had higher haemoglobinemia and body weight at weaning and lower pre-weaning morbidity and mortality than unsupplemented pigs [175]. Finally, a more recent study showed that a second iron intake at about 2 weeks of age can even be useful in organic piglets weaned at about 42 (±1.7) days of age, to ensure adequate iron intake and better piglet growth until weaning [176]. It is therefore probably appropriate to assume that the risk of anaemia is low in free-range farms where the soil provides iron in its intrinsic composition [41].…”

The Effect of Needle Reuse on Piglet Skin Puncture Force

“…Parenteral iron administration prevents iron deficiency anaemia, a condition which can reduce growth rates and increase disease susceptibility and mortality [4]. A single dose of iron may not provide sufficient iron for adequate growth, suggesting a requirement for multiple post-natum injections, particularly on organic farms where piglets experience extended suckling periods [5].…”