Zinc fate in animal husbandry systems

Abstract

Zinc (Zn) is considered in animal production systems as both an essential nutrient and a possible pollutant. While it is generally supplemented at low levels in animal diets, with less than 200 mg kg(-1) in complete feeds, it is under scrutiny due to potential accumulation in the environment. This explains why international regulations limit maximum supplementation levels in animal feeds in a stricter way. This article gives an overview of the current knowledge on the fate of zinc in animal production systems, from animal diets to animal wastes. Some analytical methods can be used for the quantification and qualification of Zn chemical forms: X-ray crystallography, electrospray tandem mass spectrometry, separation techniques, hyphenated techniques… Analysis of chelated forms issued from complex matrices, like hydrolysed proteins, remains difficult, and the speciation of Zn in diluted carriers (premix and feed) is a challenge. Our understanding of Zn absorption has made progress with recent research on ZnT/Zip families and metallothioneins. However, fine-tuned approaches towards the nutritional and metabolic interactions for Zn supplementation in farm conditions still require further studies. The speciation of zinc in pig manure and poultry litter has been a priority as monogastric animals are usually raised under intensive conditions and fed with high quantities of trace minerals, leading to high animal density and elevated quantities of zinc from animal wastes.

Drastic Change in Zinc Speciation during Anaerobic Digestion and Composting: Instability of Nanosized Zinc Sulfide

“…The Zn concentration in pig slurries is always significantly higher than in cattle slurries 8,44 because of the addition of Zn in pig feed and low intake by the animal. 45 In samples from the centralized AD plants (Central-1, -2, -3), we also observed a wide range of Zn concentrations among sites. Raw OWs with high Zn concentration…”

Effects of dietary xylo-oligosaccharide on growth performance, serum biochemical parameters, antioxidant function, and immunological function of nursery piglets

“…Because of its low digestibility, about 80% of ZnO is expelled through the Effects of dietary xylo-oligosaccharide on growth performance, serum biochemical parameters, antioxidant... Hou et al feces (Buff et al, 2005). High dietary ZnO leads to the development of Zn resistance by animal intestinal bacteria and may play a role (Cavaco et al, 2011;EFSA, 2014) in the co-occurrence of antibiotic resistance and excessive fecal Zn content (Case and Carlson, 2002;Buff et al, 2005); therefore, Zn accumulation in soil after intensive pig farming (Romeo et al, 2014) will be a serious environmental concern.…”

Effects of zinc sources and levels of zinc amino acid complex on growth performance, hematological and biochemical parameters in weanling pigs

“…Zinc (Zn) is an important trace element for the maintenance of body normal physiological functions [ 1 ]. Zn is ubiquitously distributed in animal bones, muscles, liver, kidney and skin.…”