# The effects of injectable trace mineral solutions on beef cattle performance and health during preconditioning and feedlot receiving: a systematic review and meta-analysis

## TL;DR

This study reviews whether injecting trace minerals helps beef cattle during stressful periods like preconditioning and feedlot receiving.

## Contribution

A systematic review and meta-analysis of 16 studies on injectable trace mineral effects in beef cattle.

## Key findings

- Injectable trace minerals did not significantly affect overall average daily gain or morbidity compared to saline injections.
- High-risk cattle showed increased average daily gain with injectable trace minerals, but low-risk cattle did not.
- Injectable trace minerals increased average daily gain in moderate-length studies and in B. taurus and crossbred cattle.

## Abstract

During the preconditioning and feedlot receiving phases of the beef cattle industry, animals undergo a myriad of stressors which may lead to decreased animal performance and immune system function. However, the supplementation of various trace minerals may aid in the mitigation of the negative effects attributed to these stressors. Since many animals experience decreased feed intake during these periods, producers may opt to utilize an injectable trace mineral (ITM) solution to provide prompt supplementation. However, research surrounding cattle health and production effects of such products is variable. Therefore, a meta-analysis further analyzing the effects of ITM solutions was conducted. Studies were collected through independent literature searches, resulting in 16 studies. Data was extracted as treatment means, a value with the ability to calculate standard deviations, p-values, and odds ratios, which were then analyzed within the meta package of R (v. 4.3.2). Overall, the usage of an ITM solution did not affect average daily gain (ADG  P = 0.21) or overall morbidity (P = 0.20) when compared to a saline injection. Additionally, ADG differed between risk classifications (P = 0.03) with the usage of an ITM product increasing ADG by 0.12 kg/d in high-risk cattle (no known management history; P = 0.02) with no effect in low-risk cattle (known management history; P = 0.93) when compared to a saline injection. Furthermore, the administration of an ITM did not affect ADG within the preconditioning (beginning of preconditioning period; P = 0.39) but tended to increase ADG (P = 0.09) by 0.06 kg/day within the feedlot receiving (arrival to feedlot facility) subclasses when compared to a saline injection. Average daily gain did not differ based on the inclusion (P = 0.49) or exclusion (P = 0.37) of additional oral supplementation. Additionally, ADG did not differ (P = 0.15) based on study length, accordingly, ITM usage had no effect in short (≤ 30 days; P = 0.41) or extended (≥ 60 days; P = 0.74) studies, but increased ADG by 0.07 kg/d in moderate (30–60 days; P = 0.04) studies. Lastly, ITM administration did not affect ADG within B. indicus (P = 0.42), but increased ADG (P = 0.05) by 0.03 kg/d within B. taurus cattle and increased ADG (P = 0.21) by 0.09 kg/d within crossbred cattle. In conclusion, ITM administration did not affect overall ADG or morbidity, but may increase ADG within specific production or animal circumstances.

Injectable trace mineral solutions may be a viable way to provide beef cattle with efficient trace mineral supplementation during periods of increased stress and decreased feed intake, such as during preconditioning and feedlot receiving. This systematic review and meta-analysis evaluates the effects of such solutions on cattle performance and health during these periods.