Pet emergencies rarely happen at a convenient time.

A dog gets into something at 9 p.m. on a Saturday, a cat stops eating over a holiday weekend, or a horse starts pawing and rolling after dark.

In a region as big and spread out as the Antelope Valley, the worst time to figure out where to go is in the middle of a crisis.

Here is what AV pet and horse owners should know now, before they need it.

Start with your own vet.

Call your regular veterinarian first, even after hours.

Many clinics have a recorded message that tells clients exactly where to go when the office is closed, and some offer after-hours advice to existing patients.

Urgent care in Lancaster for dogs and cats.

AV Veterinary Center, at 1055 W. Columbia Way, Suite 103, in Lancaster, offers urgent and emergency care for dogs and cats during its open hours, including weekend walk-ins from noon to 10 p.m.

The hospital asks owners to call ahead at (661) 729-1500 so the team can prepare, and to call from the parking lot instead of walking in if parvo is suspected.

Hours for doctor exams vary by day, so confirm by phone before you drive over.

The nearest round-the-clock ER.

For true middle-of-the-night emergencies, many AV families make the drive over the hill to VEG Santa Clarita, at 25820 The Old Road in Stevenson Ranch.

It is open 24 hours a day, every day of the year, takes walk-ins without appointments, and treats birds, reptiles and other exotic pets as well as dogs and cats.

You can call (661) 509-3115 and speak with a veterinarian before you leave, which helps you decide whether the trip is necessary.

From much of the Antelope Valley, plan on a drive of roughly 45 minutes to an hour, longer in traffic or wind.

Horses and livestock work differently.

There is no walk-in ER for horses, so after-hours care usually comes from your regular equine or large-animal vet's on-call line.

Becoming an established client before an emergency matters, since a vet who already knows your horse and property can respond faster.

Ask your vet now where they refer cases that need surgery or hospitalization, such as severe colic, and keep your truck and trailer ready to roll.

Poison help by phone.

If you think a pet swallowed something toxic, the ASPCA Animal Poison Control Center at (888) 426-4435 and Pet Poison Helpline at (855) 764-7661 are both available around the clock, and a fee may apply.

When it is an emergency.

Difficulty breathing, collapse, seizures, heavy bleeding, a swollen belly with unproductive retching, suspected poisoning, trauma such as being hit by a car, and straining to urinate all call for immediate care.

In horses, colic signs, a deep wound, sudden severe lameness or choke are reasons to call right away.

Get ready tonight.

Save these numbers in your phone, keep vaccination and medication records handy, and keep a carrier, leash or halter by the door.

Emergency care can be expensive, so it helps to know ahead of time whether you will use pet insurance, savings or a financing plan.

Hours and services can change, so always call ahead to confirm before you drive.

Five minutes of planning today can save precious time on the night it counts.

Helpful links

AV Veterinary Center, 1055 W. Columbia Way, Suite 103, Lancaster. Call (661) 729-1500 before you go.

VEG Santa Clarita, 25820 The Old Road, Stevenson Ranch. Open 24/7 at (661) 509-3115.

ASPCA Animal Poison Control Center, (888) 426-4435, and Pet Poison Helpline, (855) 764-7661.

AAEP colic prevention tips for horse owners.