April Cattle Checklist: CDT Boosters, Fly Control, Pre-Breeding Vaccines

April is the busiest month of the year for most small cattle operations. Four things need to happen in this window, and skipping any one typically costs you a lot more than getting them done. Here’s the concise version.

1. CDT boosters (annual, all animals)

Clostridium perfringens types C & D + Tetanus. Every animal on the property, every year, no exceptions. The vaccine runs about $2 per dose. A single case of enterotoxemia (overeating disease) in a calf runs $400+ in vet bills and often ends in death.

Time it so the booster lands 30-45 days before breeding on bred cows, or about 6 weeks before calves hit new spring pasture. For open cows and bulls, any time in April works.

2. Fly and parasite control starts NOW

Fly pressure in Texas typically peaks from May through August. If you wait until you see face flies on cattle, you’re already behind — horn fly and face fly populations double every 10-14 days in spring conditions.

Two options:

• Fly tags: slip into the ear at the same time as CDT boosters. $3 per tag, lasts 4-5 months. Rotate the active ingredient yearly (pyrethroid one year, organophosphate the next) to prevent resistance.
• Pour-ons: monthly application, easier but more labor. Effective for parasites (lice, mites) as well as flies.

For deworming specifically: do a fecal egg count before treating rather than blanket-deworming. About 30% of the herd carries 80% of the parasite load; treating that 30% is more effective and delays resistance.

3. Pre-breeding vaccines (30-day window)

If you’re pasture-breeding in May or June, pre-breeding vaccines need to go in 30 days before bull turn-out. The core stack:

• BVD (Bovine Viral Diarrhea) — prevents early embryonic loss
• IBR (Infectious Bovine Rhinotracheitis) — same
• Leptospirosis — major cause of late-term abortion
• Vibriosis / Campylobacter — venereal disease, often in breeding bulls

4. Spring pasture rotation (start this week)

The single cheapest way to improve animal performance is rotational grazing, and April is when you set the pattern for the whole year. Goal: never let cattle graze a pasture below 3-4 inches of height, and give each paddock 28-35 days of rest before return.

For a typical small operation (5-15 head, 10-30 acres), this means 3-4 paddocks minimum, moving every 7-10 days in April-May when growth is fastest. A polywire and a solar energizer will fence temporary paddocks for under $300.

5. Bonus: weight everybody

Every animal through the chute, every April. A single body condition score + weight measurement in spring tells you which cows didn’t winter well, which calves are hitting targets, and who to cull before you spend another $400/head on winter hay.

This checklist is the short version. Ranch Intel’s monthly reminders panel pulls the specific actions for your herd’s location and stage — updated every month on your dashboard.