Biomedical subjects

L H Lauerman

Publications and source records attributed to L H Lauerman.

At least 55 records · Page 3Linked to original sources

PubMed1976

Characteristics of semen changes during Brucella ovis infection in rams.

The effect of brucellosis on semen quality in rams was studied by means of artificially infecting five rams with a strain of Brucella ovis isolated in Kenya. Infection resulted in reduced semen quality including reduced total sperm output, poor motility and a high percentage of morphological abnormalities. Variation in semen quality both between and within rams appeared to be related to progress of the disease in the epididymis as well as to the distribution and severity of lesions in the reproductive tract.

Animals↗

PubMed1976

Shipping fever pneumonia in yearling feedlot cattle.

During each week of 1974, we surveyed, for illnesses and deaths, a continually changing population of yearling feedlot cattle that, for the year, totaled 407,000 animals. About 5.1% of the cattle sickened and, of these, 18.9% died. From the 3,943 fatalities, 1,988 necropsies were made. About 75% of the clinical diagnoses and 64% of the necropsy diagnoses were respiratory tract diseases; of the fatalities from respiratory tract diseases, 75% were attributed to shipping fever pneumonia. Nearly 72% of fatal cases of shipping fever pneumonia occurred during the first 45 days on feed. In the lungs of most cattle with shipping fever pneumonia, bronchiolitis, fibrinous exudate, colonies of microorganisms, lymphatic clots, intravascular clots, thromboses, and foci of necrosis were found. Pasteurella spp, Mycoplasma spp, and infectious bovine rhinotracheitis virus were isolated from pneumonic tissues. It was hypothesized that pathogenic Pasteurella spp and other microorganisms in nasal secretions transfer from the nasopharynx into the lungs by draining along the tracheal floor into ventral bronchi, bronchioles, and alveoli, and that pasteurella endotoxin, formed in infected lobules, thromboses and occludes lymphatics, capillaries, and veins and thereby causes ischemic necrosis.

Animals↗

PubMed1976

Diseases of yearling feedlot cattle in Colorado.

During all of 1974 we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle. The morbidity was 5.1%, with a case mortality of 18.9% and a population mortality of 1.0%. Both morbidity and mortality were higher during fall and winter than during spring and summer. Of the 3,943 dead cattle, 1,988 were necropsied. The most prevalent diseases were: pneumonia, 48%; diphtheria, 6%; brisket disease, 6%; hemorrhagic colitis, 5%; riding injury, 4%; bloat, 3%; calculosis, 2%; endocarditis, 2%; abomasal ulcers, 2%; bovine viral diarrhea, 2%; embolic pulmonary aneurysm, 1%; and pulmonary edema, 1%.

Animals↗

PubMed1976

Atypical interstitial pneumonia in yearling feedlot cattle.

During each week of 1974, we surveyed, for illnesses and deaths, a constantly changing population of yearling feedlot cattle that, for the year, totaled 407,000 animals. From 3,943 fatalities, 1,988 necropsies were made; of this number, 106 (5.3%) had atypical interstitial pneumonia. The death rate was higher during summer and fall than during the other seasons and was evenly distributed throughout each of the 4 stages of fattening. Gross pulmonary lesions involved both lungs and were prominent throughout the caudal (diaphragmatic) lobes. Epithelialization, hemorrhage, fibrin, hyaline membranes, emphysema, bronchiolitis, and interstitial edema were common, whereas chromatin strands, bronchiolar edema, interstitial emphysema, and obliterating bronchiolitis were less common histopathologic features.

Animals↗

PubMed1976

Brisket disease in yearling feedlot cattle.

During all of 1974, we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle maintained at 1,600 m altitude. Of 1,988 cattle necropsied, 116 (5.8%) had brisket disease. The malady occurred during all seasons but was most common throughout fall and winter. The gross changes were hypertrophy and dilatation of the right ventricle and generalizaed passive congestion. The postulated causative factors were high genetic susceptibility, rapid growth rate, previous mountain grazing, and hypoventilation with airway hypoxia.

Animals↗

PubMed1976

Fetal abomasal ulcers in yearling feedlot cattle.

During all of 1974, we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle. From the 3,943 dead cattle, 1,988 necropsies were made; of this number, 31 (1.6%) had ulcers with fatal perforations or hemorrhages; a similar additional number of necropsied cattle had innocuous ulcers as incidental findings. Ulcers developed during all seasons and all stages of fattening, but were more common during the first 45 days of winter-initiated fattening than during other times. Perforations of the abomasal wall resulted in spillage of abomasal contents into the abdominal cavity and the development of peritonitis.

Abomasum↗

PubMed1976

Sudden deaths in yearling feedlot cattle.

A survey of the causes for fatal diseases of yearling feedlot cattle was conducted on more than 407,000 cattle during a 14-month period. Of the 4,260 (1%) cattle that died during this period, 1,358 (32%) were categorized as cases of "sudden death syndrome." Of the 11 most frequent causes of the syndrome, as determined at necropsy, only 4--bloat, pulmonary aneurysms, riding injury, and hemopericardium--were considered as short-course problems and true causes of sudden death. The largest number of cases of sudden death were attributed to pneumonia (113 animals). Consequently, the sudden death syndrome is a misnomer for many long-course diseases and, in some instances, a mask for neglect because, as clinically used, the name frequently includes cattle that have been sick, often with pneumonia, for several days.

Animals↗

PubMed1976

Bronchiectasis in yearling feedlot cattle.

Thoughout all of 1974, we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle. From the 3,943 dead cattle, 1,988 necropsies were made; of the cattle necropsied, 32 (1.6%) had bronchiectasis. In this disease, the permanently dilated small bronchi and bronchioles, located in ventral parts of the lungs, were filled with accumulations of exudate and microorganisms, including Pasteurella hemolytica, Pasteurella multocida, Corynebacterium pyogenes, Escherichia coli, Salmonella anatum, Staphylococcus spp, and Mycoplasma arginini.

Animals↗

PubMed1976

Embolic pulmonary aneurysms in yearling feedlot cattle.

Throughout all of 1974, we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle. Of 1,988 cattle necropsied, 25 (1.3%) had ruptured pulmonary aneurysms and an additional 4 had gross pulmonary emboli without rupture. The emboli originated from thrombi in the caudal vena cava where that vessel closely applies to the left border of the liver and where parenchymal abscesses had developed. The emboli had lodged in the pulmonary artery, weakened its wall, and led to saccular aneurysms. Infection weakened and blood pressure ruptured the saccule and opened the adjacent bronchi. Extravasated blood dissected the tunica adventitia, formed hematomas, poured into the bronchus, and was expelled from the larynx. A portion was swallowed into the rumen, and some was coughed and blown from the nose and mouth. Deaths were attributed to exsanguination and pulmonary incapacitation.

Aneurysm↗

PubMed1976

A method for bleeding vampire bats, Desmodus rotundus murinus.

Explore the source record for details and available documents.

Animals↗

PubMed1975

Duration of Brucella ovis infection in ewes.

Twenty Romney Marsh ewes, some 5 to 40 days pregnant, were inoculated with a strain of Brucella ovis onto the scarified mucous membrane of the vagina. Establish of infection was ascertained by recovery of the organisms from blood; supramammary and inguinal lymph nodes; the vagina, after initial disappearance of the organism from this organ; and the complement fixation tests. The bacteremia was transitory or intermittent, but organisms could not be recovered from blood, or any other tissue examined, after 98 days of infection. Abortions or placentitis were not observed. It is recommended that in countries where sheep breeding is aseasonal a sexual rest of infected ewes for at least 4 months must be part of any program for the control and eradication of ram epididymitis.

Animals↗

PubMed1975

Effect of humoral antibodies on the course of Theileria parva infection (East Coast fever) of cattle.

A study was made of the effects of serum and gamma-globulins from vaccinated cattle (donor cattle) given to cattle (principals) exposed to Theileria parva infection (East Coast fever (ECF)). The principals were treated with normal serum, with serum containing high antibody titer against T parva (as evaluated by the indirect fluorescent antibody (IFA) technique), or with globulins prepared from normal and from immune serums. For exposure, the principals were inoculated with standardized suspension of the tick Rhipicephalus appendiculatus containing T parva infective particles. Comparison was made between treatments with normal serum and globulin and treatments with immune serum and globulin, using observations of time lapse after exposure to febrile response (39.5 C), to appearance of T parva macroschizonts, and to death. In addition, hematologic changes were determined. Neither the establishment of infection nor the clinical and hematologic changes in the principals were influenced by their treatment with immune serum or concentrated globulins; all died of ECF. Humoral antibodies did not protect cattle against fatal ECF, nor was enhancement of T parva infection observed.

Animals↗

PubMed1974