Zinc is an essential trace mineral for humans, animals and aquaculture alike. The symptoms caused by a zinc deficiency in humans and animals include, but are not limited to:
Zinc is also a structural constituent of about 750 Zn-finger transcription factors enabling gene transcription and is a catalytic component of approximately 2,000 enzymes. Therefore, zinc is essential for cellular processes including growth and development, DNA synthesis and RNA transcription. Additionally, zinc is known to benefit shrimp beyond growth and performance as illustrated below.
One of the main causes of a zinc deficiency is malnutrition. Illness and/or infection reduce zinc bioavailability. The replacement of fish meal in aquaculture diets may also significantly reduce zinc content and increase the levels of anti-nutritional factors, like phytic acid, which may bind trace minerals like zinc and make them less available for absorption.
A 1995 study by Paripatananont and Lovell was the first to demonstrate that ZINPRO® zinc methionine complex was three to five times more bioavailable than inorganic zinc sulfate (ZnSO4) in meeting growth requirements of channel catfish fed purified and practical diets containing phytic acid.
Davis et al. (1993) reported that L. vanammei required 33 ppm of zinc to maintain normal growth and maximize zinc concentrations in hepatopancreas. In the same study, supplementation with 200 ppm of inorganic zinc was required to overcome depressed zinc bioavailability caused by phytates and return zinc levels in hepatopancreas back to that observed in semi-purified diets without phytate.
When supplemented in shrimp diets, performance trace minerals, like Zinpro Performance Minerals®, have an absorption advantage over inorganic minerals because they are minimally antagonized by dietary components like phytic acid and utilize the amino acid transporters instead of the common metal transporters.
Two more recent studies have demonstrated how adjusting the level and source of zinc in practical L. vannamei diets influences growth, health and final product quality.
Study I showed that zinc supplementation positively and significantly affected growth and feed conversion rate (FCR), despite a high fish meal inclusion level (Figure 1, Study I). Replacing 120 ppm of zinc sulfate with just 60 ppm of zinc from Availa-Zn maintained shrimp growth and FCR, showing that Zinpro Performance Minerals is a more effective source of zinc. The most efficient FCR was seen when combining 60 ppm of zinc from Availa-Zn with 60 ppm of from zinc sulfate, indicating that higher zinc supplementation levels may be required to maximize shrimp performance.
In Study II, replacing the inorganic mineral premix (sulfates) with Zinpro Performance Minerals at one-half the rate of the inorganic mineral premix resulted in a numerically higher final body weight and 8.3% lower FCR (Figure 1, Study II). Return on investment (ROI), measured by additional income over feed cost, was 16% higher for shrimp fed Zinpro Performance Minerals at one-half the rate vs. inorganic minerals.
Additionally, Study I showed zinc supplementation in practical shrimp diets significantly enhanced antioxidant capacity and immune-related enzymes. Activity of hemolymph phenoloxidase — a crucial component of the shrimp immune system — significantly increased when zinc sulfate was partially or completely replaced with zinc from Availa-Zn (Figure 2, Study I). In addition, the hepatopancreas antioxidant capacity and immune-related enzyme activity was higher in shrimp that were fed a combination of zinc sulfate and zinc from Availa-Zn at one-half the rate (60 ppm Zn as ZnAA) of inorganic (120 ppm).
Partial or complete replacement of an inorganic mineral premix with zinc, manganese, copper, iron and selenium from Zinpro Performance Minerals improved shrimp immune status, as indicated by the increased hemocyte count and phenoloxidase activity (Figure 2, Study II). Importantly, the cumulative mortality of shrimp challenged with Vibrio harveyi was significantly reduced when the mineral inorganic premix was partially or completed replaced with performance trace minerals as illustrated below.
In both studies, zinc level and source had a significant effect on shrimp quality, namely drip and thaw loss. Supplementation of zinc from Availa-Zn in combination with zinc sulfate — or at one-half the rate of inorganic — significantly reduced drip loss in muscle and thawing loss in whole shrimp (Figure 3, Study I).
Moreover, partial or complete inorganic mineral premix replacement with performance trace minerals also reduced drip loss of peeled shrimp four days post-refrigeration (Figure 3, Study II).
Therefore, supplementation of zinc from Zinpro Performance Minerals proved superior to inorganic zinc supplementation for improved product quality.
Supplementing 60 ppm of zinc from performance trace minerals in shrimp diets alone or in combination with other trace mineral amino acid complexes proved to be an efficient approach in promoting shrimp growth, antioxidant capacity, immune response and product quality.
The high bioavailability of Zinpro Performance Minerals contributes to a more cost-efficient production of shrimp while decreasing nutrient excretion into the environment, making it a more sustainable choice as well.
To learn more about including zinc from Zinpro Performance Minerals in your shrimp nutrition program, contact your Zinpro representative today.