Coat Coloration in Feral Hogs

The coat coloration patterns observed among populations of feral hogs (also called wild hogs; Sus scrofa) are extremely diverse (Fig. 1).  Much of this variation stems from the varied ancestral origins of these populations (History of Feral Hogs in the United States).  In general, feral hog coat coloration varies from solid to mixed patterns. 

The simplest of these is the solid coloration.  This can be expressed as any of the basic colors (that is, black, red-brown, or …

Feral Hog Tusk Characteristics

The tusks of feral hogs (also called wild hogs; Sus scrofa) have long been a physical feature of these animals that has garnered significant interest from both the sport-hunting and general publics.  These teeth, technically called canine teeth (as they are in all mammals that have them), have both deciduous (i.e., temporary, “baby” or “milk”) and permanent sets.  The permanent tusks, especially in boars, represent a major element of the trophy quality of a feral hog.  It is also …

Neck Wattles in Feral Hogs

Similar to “mule-footed” hooves (Mule-Footed Feral Hogs), neck wattles are uncommon physical features that have been reported in feral hogs (also called wild hogs; Sus scrofa).  The presence of neck wattles (also called “waddles” or “tassels”) in these animals is neither widespread nor frequently observed even where they are known to occur. 

Analogous to the bell on the throat region of a moose’s neck, these structures are gristle protuberances or tubular appendages in the hog’s skin.  Neck …

“Mule-Footed” Feral Hogs

One uncommon feature that has been reported in feral hogs (also called wild hogs; Sus scrofa) is the presence of syndactylous or “mule-footed” hooves.  The mule-footed condition in swine is structurally only a slight variation from the normal cloven-hoofed condition.  Internally, it is caused by a developmental fusion of the last pair of bones of the two middle toes or digits of the foot (Fig. 1).  In some cases, the next to the last toe bones can also …

Shoulder Shields in Feral Hogs

Sexually-mature male feral hogs (also called wild hogs; Sus scrofa) possess a thickened subcutaneous layer of tissue, commonly referred to as the “shield” or “shoulder plate,” which overlies the outermost muscles in the boar’s lateral shoulder region (Fig. 1).  This unique anatomical structure, a secondary sexual characteristic found in this species, serves a reported protective function for boars fighting for breeding opportunities with estrous sows (Feral Hog Behavior).

Figure 1. Illustration of the general location of the …

How do invasive species get here?

Invasive species have been introduced through many avenues. Intentional introductions have been made for agricultural crops, landscaping, ornamental plants, and for the pet trade. Once introduced, a few species have escaped cultivation  or domestication and have established viable populations in the wild. Some of these populations not only survive, but thrive and increase.

Accidental introductions include contaminated freight such as plants, wood, or food that contain propagules of invasive species,  such as seeds, eggs, spores, or other biological material capable …

Are there different strains of the foot-and-mouth disease (FMD) virus?

There are seven immunologically distinct serotypes of the foot-and-mouth disease (FMD) virus and over 60 subtypes. The seven serotypes are A, C, O, Asia 1, SAT 1, SAT 2, and SAT 3. New subtypes occasionally develop spontaneously. The large number of virus types and subtypes creates challenges for the maintenance of vaccine stockpiles that can be deployed in the event of an outbreak. 

Strains of FMD serotype O are of most concern for disease spread into new areas. FMD serotype …

How do invasive species cause harm?

Invasive species can cause harm in so many different ways that it isn’t practical to cover them all here. So, below is just a sample to give you an idea of how pervasive this problem is. Many of these changes are things you can see happening around you.

When a non-native species is introduced into a new environment it is freed from the natural predators, parasites, or competitors from its native habitat. This gives an advantage to non-native species competing …