The term “must” describes a state of heightened aggression in large animals like elephants, leading to questions about whether other species experience it. Pet owners sometimes use the term “must rat” for intense behaviors in domestic rats. This article explores the biology of must, whether it applies to rats, and how to manage these behaviors.
The Phenomenon of “Must” in the Animal Kingdom
Must, or musth, is a physiological and behavioral period in the males of large mammal species, most notably elephants. This state is driven by a surge in reproductive hormones, with testosterone levels increasing by as much as 100 times their normal baseline. This hormonal flood transforms the animal’s disposition and physical state. It is a natural condition in healthy adult males, linked to mating and establishing dominance.
A visible sign of musth in elephants is the secretion of a thick, tar-like liquid called temporin from temporal glands between the eyes and ears. This discharge has a strong odor that signals the male’s reproductive readiness to females and his dominant state to other males.
During musth, an elephant’s behavior becomes more aggressive, restless, and unpredictable. They may engage in destructive actions, challenge other males, and pose a greater danger to humans. This heightened aggression helps a male secure more mating opportunities, sometimes allowing a smaller male to temporarily outrank a larger competitor.
“Must Rat”: Reality or Misnomer?
The term “must rat” sometimes appears in owner communities, but scientifically, it is a misnomer. Rats do not experience true musth, as they lack the specific physiological markers like temporal gland secretions or the extreme testosterone spikes that define the condition in elephants. The term is used colloquially to describe periods of intense, problematic behavior.
What owners identify as “must rat” is hormonal aggression. This behavior is most common in unneutered male rats (bucks) as they reach social maturity between 6 and 12 months of age. During this phase, a surge in testosterone can cause some rats to become more agitated and aggressive toward their cagemates or handlers.
Behaviors associated with hormonal aggression include puffing up fur (piloerection), sidling up to another rat threateningly, or aggressive scent marking. These actions can escalate from dominance squabbles to serious fighting that may cause injury. This period of heightened conflict is what owners are referring to when using the “must rat” label.
Understanding and Managing Intense Rat Behaviors
Hormonal aggression is fueled by testosterone and can become problematic in the confined space of a cage, leading to stress and physical harm. For owners dealing with an aggressive rat, several management strategies can be effective.
Veterinary options include neutering, which removes the source of testosterone and often resolves the aggression within a few weeks. A non-surgical alternative is a hormonal implant administered by a veterinarian to suppress testosterone production. Beyond veterinary intervention, environmental management is also important for reducing conflict.
- Ensure the cage is sufficiently large for the number of rats.
- Provide multiple resources like food bowls and water bottles to reduce competition.
- Offer ample enrichment such as tunnels and chew toys to redirect energy.
- Introduce new rats slowly in a neutral space to allow social bonds to form peacefully.
Recognizing signs of serious aggression, such as frantic squeaking or biting that draws blood, is a signal to separate the rats and consult a professional.