An Electric fence (single wire at knee height) should take care of the dogs. Make sure you install small flags by the wire and signs warning people of the fence. After the dogs get zapped a time or two I suspect they won’t head your direction any longer.
Since the dogs appear aggressive to you I suspect you may be able to just shoot them during the time they are aggressive and on your property. i strongly suggest talking with a local lawyer about the legality of it first.
and what county is this?
It does appear that under texas law the dogs may be able to be classified as dangerous dogs
2) "Dangerous dog" means a dog that:
(A) makes an unprovoked attack on a person that causes bodily injury and occurs in a place other than an enclosure in which the dog was being kept and that was reasonably certain to prevent the dog from leaving the enclosure on its own; or
(B) commits unprovoked acts in a place other than an enclosure in which the dog was being kept and that was reasonably certain to prevent the dog from leaving the enclosure on its own and those acts cause a person to reasonably believe that the dog will attack and cause bodily injury to that person.
And if you are successful in havimg the dog listed listed as a dangerous dog, they are obligated by state law to restrain it
§ 822.042. Requirements for Owner of Dangerous Dog(a) Not later than the 30th day after a person learns that the person is the owner of a dangerous dog, the person shall:
(1) register the dangerous dog with the animal control authority for the area in which the dog is kept;
(2) restrain the dangerous dog at all times on a leash in the immediate control of a person or in a secure enclosure;
(3) obtain liability insurance coverage or show financial responsibility in an amount of at least $100,000 to cover damages resulting from an attack by the dangerous dog causing bodily injury to a person and provide proof of the required liability insurance coverage or financial responsibility to the animal control authority for the area in which the dog is kept; and
(4) comply with an applicable municipal or county regulation, requirement, or restriction on dangerous dogs.
(b) The owner of a dangerous dog who does not comply with Subsection (a) shall deliver the dog to the animal control authority not later than the 30th day after the owner learns that the dog is a dangerous dog.
(c) If, on application of any person, a justice court, county court, or municipal court finds, after notice and hearing as provided by Section 822.0423, that the owner of a dangerous dog has failed to comply with Subsection (a) or (b), the court shall order the animal control authority to seize the dog and shall issue a warrant authorizing the seizure. The authority shall seize the dog or order its seizure and shall provide for the impoundment of the dog in secure and humane conditions.