Effect of lasalocid on fall-calving beef cows

Area of Science:

• Animal Science
• Ruminant Nutrition
• Beef Cattle Production

Background:

• Lasalocid is an ionophore antibiotic used in beef cattle diets.
• Understanding its long-term effects on reproductive performance and production is crucial for optimal herd management.

Purpose of the Study:

• To evaluate the effects of lasalocid supplementation on fall-calving beef cows.
• To assess impacts on cow body condition, milk production, calf growth, and reproductive efficiency.

Main Methods:

• A 196-day trial involving 42 crossbred cow-calf pairs.
• Two treatment groups: 0 mg/head/day (control) and 200 mg lasalocid/head/day.
• Cows were fed haylage and grass hay, with pasture access except during breeding.

Main Results:

• Lasalocid did not significantly affect cow weight changes or body condition.
• Milk yield showed a slight, non-significant increase in treated cows; milk fat and protein percentages were unaffected.
• Calf gain and 205-day adjusted weaning weights were not influenced by lasalocid treatment.
• Average days open for cows remained similar between treatment groups.

Conclusions:

• Long-term feeding of lasalocid at 200 mg/head/day had no detrimental effects on fall-calving beef cows.
• Lasalocid supplementation did not improve cow performance, milk yield, calf growth, or reproductive parameters in this study.