The Breeder Blog

Whelping Box Rails: Creating a Safe Haven for Newborn Puppies

by Phenyx Media on Sep 23, 2023

my breeder supply heated whelping kit

In the world of puppies and their journey to maturity, the first few weeks of life are undeniably the most critical. The environment in which these fragile beings spend their initial days and weeks needs to be as secure and comforting as a mother's embrace. This is where whelping box rails step into the spotlight as an indispensable tool for a pet parent. A simple yet effective tool, these rails create a safe haven for the furriest of newborns.

Introduction to Whelping Box Rails

Whelping box rails, also referred to as anti-crush or pig rails, are a critical component of a well-designed whelping box. Designed to provide a safe barrier between the pups and the box walls, they prevent the mother from unintentionally smothering her offspring while lying against the box sides. This ingenious addition to the whelping box offers newborn pups a pocket of safety, where they can move and sleep without fear of accidental injury.

Importance of Safety for Newborn Puppies

whelping kit rails

Safety for newborn puppies isn't just crucial—it's a matter of life and death. Their tender age and underdeveloped senses make them highly susceptible to various risks, from suffocation to hypothermia. Their inability to regulate body temperature requires a warm environment to prevent cold-related complications. Additionally, their lack of mobility makes it easy for them to be trapped against a box wall or beneath their mother. That's where whelping box rails offer a solution, creating a protective barrier and warm zone for the puppies to thrive.

PVC Whelping Rail Adapters

PVC whelping rail adapters form a key part of the whelping box safety apparatus. Their role is to keep the PVC pipes, which serve as the actual rails, firmly in place. Made of robust and easy-to-clean material, these adapters not only ensure that the rails don't budge but also allow for easy adjustments or replacements when needed.

Measurement and Supplying the PVC Pipe

Setting up the whelping box rails requires an accurate measurement of your box or crate's interior dimensions. For this, you will need a 1-1/2" PVC Pipe. Measure the inside of the crate, and subtract 5" for the length and 5" for the width. These dimensions will provide sufficient clearance for the puppies to move safely. Most home improvement stores, such as Lowe's, Home Depot, or Ace, stock PVC pipes, and they may even cut them to your specifications.

Choosing the Right Crate

a heated whelping kit including a cage

While any crate can technically house a litter of puppies, not all crates are created equal when it comes to providing the best whelping environment. Several brands stand out for their quality and user-friendly design, such as Midwest Supply, Paws & Pals, and Amazon Basics. A crate with a double door, for instance, offers convenience and versatility. It facilitates easy access to puppies, helping you monitor their growth, clean the box, and handle any emergencies quickly.

The Threats of Hypothermia and Smothering for Newborns

The biggest threats to newborn puppies are hypothermia and smothering. Puppies, especially newborns, lack the ability to thermoregulate. That means they can't maintain their body temperature independently, making them highly susceptible to hypothermia. Similarly, due to their limited mobility and the mother dog's size, they risk being smothered without a protective system in place. The heated whelping box with pig rails significantly mitigates these risks, creating a controlled environment for the pups to grow safely.

The Heated Whelping Box Kit

To address the threats of hypothermia and smothering, consider investing in a heated whelping box kit. This kit typically includes a heating system and a pig rail. The heating system ensures that the box maintains an appropriate temperature to keep the pups warm, while the pig rail prevents the puppies from being crushed or suffocated by the mother.

The Concept of the Pig Rail

A pig rail, installed just above the floor of the whelping box, offers an escape zone for the pups. When the mother dog leans or lies against the box wall, the rail creates a safe space beneath her where the pups can retreat. This preventive measure significantly reduces the risk of the pups being suffocated or crushed.

The Heating Mechanism and its Benefits

In a heated whelping box, the floor beneath the pig rail is heated, creating a warm, cozy spot for the newborns. This targeted heating serves dual purposes: it keeps the pups warm and encourages them to stay within the safe zone defined by the pig rail. Moreover, it offers an added advantage – it does not subject the mother dog to excessive heat, reducing stress and discomfort.

Importance of the Nursing Area for Puppies

A designated nursing area in the whelping box is essential for the health and survival of the puppies. The nursing zone, combined with the heat from the box, encourages the pups to stay within the safe perimeter for nursing and resting, thus promoting their growth and preventing potential mishaps.

Benefits for the Mother Dog

Whelping box rails not only protect puppies but also offer benefits for the mother dog. They reduce the stress associated with caring for her young by providing a secure space where she can rest without worrying about harming her puppies. The heating mechanism also ensures that the mother dog is not continuously subjected to heat, offering her a more comfortable whelping environment.

What's Included in the Kit

The standard heated whelping box kit includes the PVC rail adapters that secure the safety rails in place. Remember, however, the kit does not include the PVC rails or crate – you will need to supply these separately based on the size and requirements of your specific setup.


Whelping box rails play an instrumental role in creating a safe and secure environment for newborn puppies. By offering a protective barrier and a warm nesting area, these rails significantly reduce the risks of hypothermia and suffocation, paving the way for healthy, happy puppies. As a pet parent, investing in a well-equipped whelping box is an act of love and care for your canine family.

Frequently Asked Questions

  1. What is a whelping box rail?

A whelping box rail, also known as a pig rail, is a safety feature installed in a whelping box. It creates a protective barrier to prevent newborn puppies from being accidentally crushed or suffocated by their mother.

  1. How do I measure for a PVC pipe for my whelping box rails?

To measure for the PVC pipe, calculate the internal dimensions of your crate. Subtract 5 inches from the length and width to allow for sufficient clearance for the puppies.

  1. What is the purpose of a heated whelping box?

A heated whelping box provides a warm environment that helps maintain the body temperature of newborn puppies, preventing hypothermia.

  1. What is included in a whelping box kit?

A typical heated whelping box kit includes PVC rail adapters. However, you will need to supply the PVC rails and the crate separately.

  1. How does a pig rail benefit the mother dog?

A pig rail provides a safe space for the puppies, reducing stress for the mother dog. She can rest without worrying about accidentally harming her puppies, and the heating mechanism doesn't expose her to excessive heat, ensuring her comfort.