Detailed Explanation of Various Reproductive Organ Diseases in Cattle (Part One)

I. Endometritis

Is an important cause of infertility in cattle, divided into acute and chronic types.

Causes and symptoms: It is caused by the invasion of bacteria and other microorganisms after calving (including abortion, management of dystocia, and mating). Brucellosis, trichomoniasis, improper handling, and drug stimulation can all serve as triggering factors. During acute attacks, body temperature rises, appetite decreases, the animal is listless, arches its back, strains, and urinates frequently. Mucous and purulent exudate flows from the vulva, with more discharge when lying down, and there is a fishy odor. On rectal examination, an elevated temperature can be felt, the uterine horns become enlarged, thickened, and sunken, with weak contraction response, and the uterus has a fluctuating feel. During chronic inflammation, the estrous cycle is abnormal, repeated mating fails to achieve conception, or silent abortion occurs. When the cow is in estrus or lying down, turbid mucus with flocculent material (including transparent mucus with small floccules) flows from the vulva. The mucous membrane of the vagina and cervical opening is congested and swollen, and the cervix is slightly open.

Treatment: Flushing the uterus is an effective method for treating chronic and acute inflammation. Various solutions can be selected, such as sodium chloride saline, potassium permanganate, furacilin, rivanol, and chlorhexidine, followed by infusion of antibiotics such as penicillin, streptomycin, and chlortetracycline. The selection of antibiotics should be made through drug sensitivity testing.

II. Premature Birth and Abortion

Refers to the disruption of the gestational relationship between the embryo or fetus and the mother, resulting in termination of pregnancy. In cattle, loss before 210 days of gestation is abortion, while birth between 210 and 269 days of gestation is called premature birth.

Causes and symptoms: There are many causes of abortion, such as infectious abortion and parasitic abortion. General abortion also includes interruption of nutrition between mother and fetus, disorders of reproductive hormone secretion, external force (or mechanical), and toxic causes, most of which are caused by improper feeding management or unbalanced rations. In early pregnancy, the embryo is still not fully developed and is absorbed by the mother, manifesting only as the disappearance of the corpus luteum of pregnancy. Estrus reappears, and it is not easily detected clinically. At about 2 months of gestation, the fetus is basically formed (fetal body length reaches 8 cm). For some cows at 3 to 7 months of gestation, abortion will show warning signs, such as swelling and congestion of the vulva, discharge of mucus mixed with blood, and enlargement of the mammary glands, which may even produce milk. After abortion, some cows show straining, arching of the back, and frequent urination. If the expelled fetus is edematous, emphysematous, dark in color, necrotic, putrid, and foul-smelling, it is an abortion caused by uterine inflammation. In cases caused by trauma, the fetus is mostly fresh in color, and a live fetus may even be delivered. It is only discovered through rectal examination. If the fetus is mummified or only bones remain, it is mostly due to death of the fetus and absorption of water, or corruption after infection by pathogenic microorganisms in the uterus, with soft tissues decomposed and liquefied and then expelled, while bones remain. The corpus luteum of pregnancy on the ovary still exists, so it is not easily detected clinically. This is also why sometimes after pregnancy testing has confirmed a pregnant cow, another pregnancy test is still performed before dry-off. Treatment: Statistics in recent years show that aborted cows account for more than 10% of cows of breeding age, resulting in considerable economic loss. Prevention should mainly start with improving feeding management, actively detecting diseased cows and giving thorough treatment in advance, and reducing contamination during handling (before and after calving and during mating). If signs of abortion are discovered, drugs can be used to prevent abortion, such as progesterone, chloral hydrate, and oral administration of Chinese herbal medicines to help stabilize pregnancy. If abortion cannot be prevented, assistance with delivery should be attempted (using methods for managing dystocia). After handling, the cow should be managed to prevent the occurrence of uterine inflammation.