Delaying growth-promoting implants until day 64 of the feeding period improved feed efficiency by 4% and produced leaner meat with larger muscle areas in beef cattle, according to a 2026 study of 232 steers published in Translational Animal Science. Gram Research analysis shows that both delayed implants and early feed restriction produced similar final cattle weights and meat quality compared to standard practices, giving farmers flexibility in their management strategies without sacrificing profitability or meat characteristics.
Researchers tested whether limiting how much food young beef cattle eat and delaying when they receive growth-promoting implants would affect their final size and meat quality. Using 232 Charolais cross steers over a 85-day study, they compared cattle that ate freely versus those limited to 92% of normal intake, and cattle that received implants immediately versus 64 days into the feeding period. According to Gram Research analysis, both strategies produced similar final weights and meat quality, but delaying implants improved feed efficiency and created leaner meat with larger muscle areas. This finding suggests farmers have flexibility in managing cattle growth without sacrificing meat quality or final outcomes.
Key Statistics
A 2026 study of 232 Charolais cross steers found that delaying growth-promoting implants until day 64 improved feed efficiency by 4% compared to implanting on day 1, according to research published in Translational Animal Science.
Restricting feed intake to 92% of normal for the first 63 days produced similar final body weights and hot carcass weights as unrestricted feeding in a 232-steer trial, demonstrating that early feed restriction does not reduce final meat production.
Delayed implant timing shifted carcass yield grade distribution toward higher quality grades (Yield Grades 1 and 2) in 55% more cattle compared to early implanting, with statistical significance at P = 0.02 in the 232-steer study.
Cattle receiving delayed implants had 3.2% larger ribeye muscle area and 8.1% less rib fat thickness compared to cattle implanted on day 1, producing leaner meat with greater muscle development in the 85-day feeding trial.
The Quick Take
- What they studied: Whether limiting feed intake and delaying growth-promoting implants in beef cattle would change how fast they grow, how efficiently they convert feed to meat, and the quality of their final meat.
- Who participated: 232 young Charolais cross steers (a beef cattle breed) weighing about 1,055 pounds on average at the start. Cattle were divided into 32 pens and randomly assigned to different feeding and implant strategies over an 85-day period.
- Key finding: Delaying implants until day 64 improved feed efficiency by 4% and created leaner meat with larger muscle areas compared to immediate implants, while feed restriction and delayed implants both produced similar final weights and meat quality to standard practices.
- What it means for you: Cattle farmers can choose to delay growth implants or restrict early feed intake without losing money on final cattle weight or meat quality. This flexibility may help farmers manage costs or meet specific market demands for leaner beef. However, these findings apply specifically to beef cattle management and may not translate to other livestock or human nutrition.
The Research Details
Researchers divided 232 young beef steers into 32 pens and tested four different management strategies in a controlled experiment. Half the cattle received growth-promoting implants (a hormone treatment) on day 1, while the other half received them on day 64. Simultaneously, half the cattle ate as much feed as they wanted throughout the 85-day study, while the other half were limited to 92% of normal intake for the first 63 days, then allowed to eat freely for the remaining 22 days. This created four groups to compare: early implant with free feeding, early implant with restricted feeding, delayed implant with free feeding, and delayed implant with restricted feeding.
The researchers carefully measured how much feed each group ate, how much weight they gained, and how efficiently they converted feed into body weight. After the 85-day feeding period ended, they processed the cattle and measured meat quality characteristics including fat thickness, muscle size, and marbling (fat within the meat). They used statistical analysis to determine whether differences between groups were meaningful or just due to chance.
This research design allows farmers to understand the real-world effects of two common management decisions: when to give growth implants and whether to restrict early feed intake. By testing both strategies together, researchers could see if they work better or worse when combined. The study used realistic farm conditions with cattle in outdoor pens, making the results more applicable to actual farming operations than laboratory studies would be.
This study has several strengths: it included a large number of cattle (232), used random assignment to treatment groups to reduce bias, and measured multiple important outcomes including growth, feed efficiency, and meat quality. The researchers used proper statistical methods to analyze their data. However, the study was conducted at a single location with one breed type, so results may vary in different regions or with different cattle breeds. The study was published in a peer-reviewed scientific journal, meaning other experts reviewed the methods and findings before publication.
What the Results Show
During the first 63 days when feed was restricted, cattle eating freely gained more weight and ate more feed than restricted cattle, which was expected. However, by the end of the 85-day period, all four groups reached similar final weights regardless of whether they had restricted feed early or received implants early versus late. This means the cattle that ate less early on caught up in growth during the final 22 days when all groups could eat freely.
The most important difference appeared in feed efficiency, which measures how much feed is needed to produce a pound of meat. Cattle that received delayed implants (day 64) converted feed to meat 4% more efficiently than cattle receiving implants on day 1. This efficiency advantage occurred during days 64 to 85, suggesting the delayed implant timing worked better during that specific period.
Carcass quality measurements showed that delayed implants produced leaner meat with less fat thickness on the ribs, but larger muscle areas (ribeye). The meat quality score (marbling) was similar across all groups. The yield grade distribution, which categorizes meat quality for market purposes, shifted toward higher quality grades in the delayed implant group.
Feed intake as a percentage of body weight was higher in the restricted feeding group, meaning they ate a larger proportion of their body weight even though the absolute amount was less. This suggests their bodies were working harder to maintain growth despite limited food. Energy calculations based on performance data did not differ significantly between groups, indicating that the different feeding and implant strategies did not substantially change the overall energy requirements or utilization.
Previous research on beef cattle has shown that growth-promoting implants generally increase weight gain and feed efficiency, and that feed restriction early in the feeding period can reduce costs without severely limiting final weight. This study confirms those general findings but adds new information: delaying implants until mid-way through the feeding period can actually improve feed efficiency compared to early implanting, and the combination of strategies produces predictable, manageable results. The finding that restricted cattle catch up in weight during the final phase aligns with previous research showing that compensatory growth occurs when cattle return to full feeding after restriction.
This study was conducted with only one breed type (Charolais cross steers) at one location, so results may differ with other cattle breeds or in different climates. The study lasted only 85 days, which is shorter than some commercial feeding periods, so long-term effects are unknown. The implant dose and type used in this study may not represent all implant products available to farmers. Additionally, the study did not measure economic costs, so farmers cannot determine from this research alone whether the improved feed efficiency of delayed implants justifies the management complexity of changing implant timing.
The Bottom Line
Based on this research, beef cattle farmers can confidently use either early or delayed implant timing without expecting major differences in final cattle weight or meat quality. Delaying implants until day 64 may provide a slight advantage in feed efficiency (4% improvement) and produce leaner meat with larger muscles, which some markets prefer. Feed restriction during the first 63 days reduces feed costs without harming final outcomes, though it requires more careful management. These recommendations apply specifically to beef cattle in finishing operations and should be adapted based on individual farm conditions, market demands, and economic factors.
Beef cattle farmers and ranchers managing finishing cattle (cattle in the final growth phase before processing) should consider these findings when planning their feeding and implant strategies. Meat processors and retailers interested in specific meat quality characteristics may find the leaner meat profile from delayed implants valuable. This research does not apply to dairy cattle, breeding cattle, or other livestock species. Consumers interested in beef production methods may find this information relevant to understanding farming practices.
The effects measured in this study occurred over an 85-day feeding period. Farmers implementing these strategies would see results within this timeframe. The feed efficiency improvements from delayed implants appeared specifically during days 64 to 85, suggesting that the benefits emerge during the later stages of the feeding period. Farmers should expect to see weight gain differences during the first 63 days of restriction, followed by catch-up growth during the final 22 days.
Frequently Asked Questions
Does delaying growth implants in beef cattle affect how much meat they produce?
No, delaying implants until day 64 produced similar final weights and carcass sizes as early implanting in a 232-steer study. However, delayed implants improved feed efficiency by 4% and created leaner meat with larger muscles, which some markets prefer.
Can farmers limit how much feed beef cattle eat without losing money on final weight?
Yes, restricting feed to 92% of normal intake for 63 days produced similar final weights as unrestricted feeding in this 232-steer trial. Cattle caught up in growth during the final 22 days when feed was unlimited, reducing early feed costs without sacrificing final outcomes.
What is the best time to give growth implants to finishing beef cattle?
This study found that delaying implants until day 64 improved feed efficiency by 4% and produced higher quality meat grades compared to day 1 implanting. The best timing depends on your farm’s specific goals, market demands, and economic factors.
How does feed restriction affect meat quality in beef cattle?
Feed restriction during the first 63 days did not significantly change meat quality scores or marbling in this 232-steer study. However, combining feed restriction with delayed implants produced leaner meat with larger muscle areas, which represents higher quality for some market segments.
Will cattle catch up in weight after early feed restriction?
Yes, cattle that received restricted feed for 63 days caught up completely in weight during the final 22 days of unrestricted feeding, reaching similar final weights as cattle fed freely throughout the entire 85-day period.
Want to Apply This Research?
- Track daily feed intake as a percentage of cattle body weight and average daily weight gain separately for the first 63 days and final 22 days of the feeding period. Record implant administration date and type. Compare actual feed efficiency (pounds of feed per pound of gain) between implant timing strategies to verify whether delayed implants improve efficiency on your farm.
- Farmers using a cattle management app could set reminders for implant administration on day 1 versus day 64 to test both strategies in separate pens. Use the app to log daily feed amounts offered and actual intake, allowing real-time comparison of feed restriction effectiveness. Document final weights and carcass measurements to track whether results match this study’s findings on your specific farm.
- Establish a long-term tracking system comparing feed efficiency, final weight, and carcass quality metrics across multiple feeding cycles using different implant timing strategies. Record environmental conditions, cattle health events, and feed quality to identify factors that may modify the study’s results. Compare your farm’s results to this research baseline to determine whether delayed implants provide economic benefits that justify the management changes.
This research applies specifically to beef cattle management in finishing operations and may not apply to other livestock species, dairy cattle, or breeding animals. Results were obtained from one breed type at one location and may vary with different cattle breeds, climates, or farm conditions. This study does not include economic analysis, so farmers should consult with agricultural economists and their veterinarians before implementing these strategies. Individual farm results may differ based on feed quality, cattle genetics, health management, and environmental factors. This information is intended for agricultural professionals and should not be applied without consideration of local conditions and expert consultation.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.