RESUMEN
Vitamin D receptor activation has been associated with increased serum creatinine and reduced estimated glomerular filtration rates, raising concerns that its use may be detrimental to kidney function. Here we studied the effect of vitamin D receptor activation on serum creatinine, creatinine generation, and its clearance. We measured baseline serum creatinine and 24-h urine creatinine in 16 patients with chronic kidney disease. The measurements were repeated every day for 7 days, during which time the patients received 2 µg paricalcitol, an orally active vitamin D receptor activator, every morning. At 4 days after stopping the vitamin analog, measurements were continued for 3 days. Geometric mean parathyroid hormone levels decreased from 77 pg/ml at baseline to 43 pg/ml at the end of treatment and significantly rebounded to 87 pg/ml following paricalcitol withdrawal, thereby supporting the biological efficacy of the analog dose used. With this therapy, the serum creatinine significantly increased at a rate of 0.010 mg/dl/day and urine creatinine at a rate of 17.6 mg/day. Creatinine and iothalamate clearances did not change, whereas urine albumin decreased insignificantly. Thus, short-term vitamin D receptor activation increases creatinine generation and serum creatinine, but it does not influence the glomerular filtration rate.
Asunto(s)
Creatinina/sangre , Ergocalciferoles/administración & dosificación , Tasa de Filtración Glomerular/efectos de los fármacos , Enfermedades Renales/tratamiento farmacológico , Riñón/efectos de los fármacos , Receptores de Calcitriol/agonistas , Administración Oral , Anciano , Albuminuria/sangre , Albuminuria/tratamiento farmacológico , Albuminuria/fisiopatología , Albuminuria/orina , Biomarcadores/sangre , Biomarcadores/orina , Enfermedad Crónica , Creatinina/orina , Esquema de Medicación , Femenino , Humanos , Indiana , Ácido Yotalámico , Riñón/metabolismo , Riñón/fisiopatología , Enfermedades Renales/sangre , Enfermedades Renales/fisiopatología , Enfermedades Renales/orina , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Receptores de Calcitriol/metabolismo , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Plasma transfusions have been used clinically in the management of neonates with failure of passive transfer. No studies have evaluated the effect of IV serum transfusions on serum IgG concentrations in dairy calves with inadequate transfer of passive immunity. HYPOTHESIS: A commercially available serum product will increase serum immunoglobulin concentration in calves with inadequate transfer of colostral immunoglobulins. ANIMALS: Thirty-two Jersey and Jersey-Holstein cross calves with inadequate colostral transfer ofimmunoglobulins (serum total protein < 5.0 g/L). METHODS: Thirty-two calves were randomly assigned to either control (n = 15) or treated (n = 17) groups. Treated calves received 0.5 L of a pooled serum product IV. Serum IgG concentrations before and after serum transfusion were determined by radial immunodiffusion. RESULTS: Serum protein concentrations increased from time 0 to 72 hours in both control and transfused calves and the difference was significant between the control and treatment groups (P < .001). Mean pre- and posttreatment serum IgG concentrations in control and transfused calves did not differ significantly. Median serum IgG concentrations decreased from 0 to 72 hours by 70 mg/dL in control calves and increased over the same time interval in transfused calves by 210 mg/dL. The difference was significant between groups (P < .001). The percentage of calves that had failure of immunoglobulin transfer 72 hours after serum transfusion was 82.4%. CONCLUSIONS AND CLINICAL IMPORTANCE: Serum administration at the dosage reported did not provide adequate serum IgG concentrations in neonatal calves with inadequate transfer of colostral immunoglobulins.
Asunto(s)
Transfusión Sanguínea/veterinaria , Calostro/química , Inmunidad Materno-Adquirida , Inmunoglobulina G/sangre , Animales , Animales Recién Nacidos , Bovinos , Industria Lechera , FemeninoRESUMEN
Cryptosporidiosis is one of the most common causes of infectious diarrhea in people. Although dairy calves are high-risk hosts, the role of other livestock, pets, and humans in the disease should not be underestimated. Some Cryptosporidium species and strains are specific to people, others are specific to animals while some are zoonotic pathogens. Cryptosporidium hominis is the species responsible for the majority of human cases in the United States, Sub-Saharan Africa, and Asia, while Cryptosporidium parvum accounts for more human cases in Europe and particularly in the United Kingdom. A deeper understanding of Cryptosporidium host range, reservoirs, and transmission is needed to develop preventive strategies to protect the general public.
Asunto(s)
Bovinos , Criptosporidiosis/transmisión , Cryptosporidium/clasificación , Animales , Criptosporidiosis/diagnóstico , Criptosporidiosis/parasitología , Criptosporidiosis/veterinaria , HumanosRESUMEN
Cytauxzoon felis produces a disease in domestic cats in the Midwest (U.S.A.), which often leads to a fatal outcome. Although the clinical disease process is well described, there are still many unanswered questions about this organism. For example, it is unknown whether species of ticks other than Dermacentor variabilis can serve as vectors for transmission. With recent reports of surviving cats from limited geographic areas, another relevant question is the potential for genetically less virulent organism strains. This study evaluated 352 individual or pooled tick samples (1,362 total ticks) for the presence of C. felis small subunit ribosomal RNA and internal transcribed spacer 1 (ITS-1) region genes using a polymerase chain reaction (PCR). These ticks were collected from dogs and cats in several Missouri counties, including 10 from cats diagnosed with cytauxzoonosis. Only 3 positive C. felis samples were identified in Amblyomma americanum nymphs, and there was very limited genetic variation noted in both genes. The small number of positive samples did not allow the study to determine which PCR analysis was more sensitive. This is the first known report of ITS-1 gene identification and sequencing for C. felis. It is also the first published investigation of genetic variation in C. felis.
Asunto(s)
Vectores Arácnidos/parasitología , ADN Espaciador Ribosómico/química , Ixodidae/parasitología , Piroplasmida/genética , ARN Ribosómico/genética , Animales , Enfermedades de los Gatos/parasitología , Enfermedades de los Gatos/transmisión , Gatos , ADN Protozoario/química , Perros , Eritrocitos/parasitología , Missouri , Piroplasmida/aislamiento & purificación , Reacción en Cadena de la Polimerasa/veterinaria , Infecciones Protozoarias en Animales/parasitología , Infecciones Protozoarias en Animales/transmisión , ARN Protozoario/genética , Alineación de Secuencia/veterinariaRESUMEN
A procedure isolating immunoglobulins specific for common gram-negative bacterial core antigens is described. A polyclonal reagent was purified by ammonium sulfate precipitation, dialysis, and column affinity chromatography. The initial vaccinal antigen was an Ra mutant Escherichia coli O111:B4 (strain J5). The capture antigen was lipopolysaccharide derived from an Ra mutant, Salmonella typhimurium TV119 covalently-linked to an agarose matrix. Column eluants were characterized in terms of total protein concentration, IgG concentration, and EIA titer recognizing E. coli (J5). Low protein, low IgG, high EIA reading fractions were isolated, demonstrating the utility of the described technique to purify broad spectrum cross-reactive immunoglobulin reagents.
Asunto(s)
Anticuerpos Antibacterianos/aislamiento & purificación , Antígenos Bacterianos/inmunología , Bacterias Gramnegativas/inmunología , Animales , Bovinos , Cromatografía de Afinidad , Reacciones Cruzadas , Escherichia coli/inmunología , Técnicas para Inmunoenzimas , Prueba de Limulus , Lipopolisacáridos/inmunología , Salmonella typhimurium/inmunologíaRESUMEN
We studied chlorpyrifos, an insecticide present in a commercial dip for treating ectoparasites in dogs, to estimate the amount of transferable residues that children could obtain from their treated pets. Although the chlorpyrifos dip is no longer supported by the manufacturer, the methodology described herein can help determine transferable residues from other flea control insecticide formulations. Twelve dogs of different breeds and weights were dipped using the recommended guidelines with a commercial, nonprescription chlorpyrifos flea dip for 4 consecutive treatments at 3-week intervals (nonshampoo protocol) and another 12 dogs were dipped with shampooing between dips (shampoo protocol). The samples collected at 4 hr and 7, 14, and 21 days after treatment in the nonshampoo protocol averaged 971, 157, 70, and 26 microg chlorpyrifos, respectively; in the shampoo protocol the samples averaged 459, 49, 15, and 10 microg, respectively. The highest single sample was about 7,000 microg collected at 4 hr. The pretreatment specific activities in the plasma of the dogs were about 75 nmol/min/mg protein for butyrylcholinesterase (BChE), and 9 nmol/min/mg protein for acetylcholinesterase (AChE). BChE was inhibited 50-75% throughout the study, and AChE was inhibited 11-18% in the nonshampoo protocol; inhibition was not as great in the shampoo protocol. There was no correlation (pAsunto(s)
Acetilcolinesterasa/metabolismo
, Cloropirifos/farmacocinética
, Insecticidas/farmacocinética
, Residuos de Plaguicidas/farmacocinética
, Animales
, Cloropirifos/administración & dosificación
, Perros
, Exposición a Riesgos Ambientales
, Femenino
, Cabello/química
, Insecticidas/administración & dosificación
, Masculino
, Control de Plagas
, Siphonaptera
RESUMEN
Serologic responses in 61 calves 3 to 34 days of age following immunization with bacterins containing a heat-killed rough mutant, Escherichia coli 0111:B4 (strain J5) were determined by an enzyme-linked immunosorbent assay specific for the IgG isotype. Administration of either heat-killed bacteria or oil-based adjuvants alone failed to enhance serologic recognition of common core antigens when comparing to nonvaccinate controls. Increased titers were uniquely and specifically limited to calves receiving the antigen in an oil emulsion. In a second experiment, age and initial, passively acquired titer recognizing the vaccinal antigen were not found to have any effect on the magnitude of the humoral response of 57 calves following immunization.
Asunto(s)
Anticuerpos Antibacterianos/biosíntesis , Bovinos/inmunología , Escherichia coli/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Factores de Edad , Animales , Animales Recién Nacidos , Antígenos Bacterianos/administración & dosificación , Calostro/inmunología , Inmunidad Materno-Adquirida , Inmunización , Inmunoglobulina G/biosíntesisRESUMEN
The mobility of pseudomonic acid A in dimethyl sulfoxide-d6 solution has been determined from 13C spin-lattice relaxation time measurements at two field strengths. The central tetrahydropyran ring reorientates isotropically with a rotational correlation time of approximately 280 picoseconds/ radian . Both side-chains exhibit marked segmental motion with correlation times decreasing to only approximately 50 picoseconds/ radian at the end of the nonanoic acid side-chain.
Asunto(s)
Antibacterianos , Fenómenos Químicos , Química , Ácidos Grasos , Espectroscopía de Resonancia Magnética/métodos , Conformación Molecular , MupirocinaRESUMEN
Two new beta-lactams have been isolated from strains of Serratia and Erwinia sp. and identified as (3R,5R)- and (3S,5R)-carbapenam-3-carboxylic acid. These novel carbapenams lack antibacterial activity, are resistant to both beta-lactamases I and II from Bacillus cereus and are not detected by the lactamase induction assay. Radiolabelled and stable isotope experiments have established that both metabolites together with the antibiotic 5R-carbapenem-3-carboxylic acid are glutamate and acetate derived. A number of possible pathways for the biosynthesis of these compounds as well as their relationship to the more complex members of the carbapenem family of beta-lactam antibiotics are discussed.
Asunto(s)
Acetatos/metabolismo , Antibacterianos/biosíntesis , Carbapenémicos , Glutamatos/metabolismo , Lactamas , Serratia/metabolismo , Isótopos de Carbono , Radioisótopos de Carbono , Fenómenos Químicos , Química , Cromatografía Líquida de Alta Presión , EstereoisomerismoRESUMEN
Two novel isoleucyl tRNA synthetase inhibitors, SB-203207 and SB-203208 have been isolated from a Streptomyces sp. and found to be structurally related to altemicidin. Structures of SB-203207 and SB-203208 have been deduced by a combination of spectroscopic techniques, derivatisation, hydrolysis studies and found to be 4-(aminocarbonyl)-7-[[(2-amino-3-methylpentanoyl)aminosul phonyl]acetamido]-2,4a,5,6,7,7a-hexahydro-6-hydroxy-2-methyl-1H-2- pyrindine-7-carboxylic acid (1) and 4-(aminocarbonyl)-7-[[(2-amino-3-methyl pentanoyl)-aminosulphonyl]acetamido]-2,4a,5,6,7,7a-hexahydro-6-(2- amino-3-phenylbutanoyl oxy)-2-methyl-1H-2-pyrindine-7-carboxylic acid (2), respectively.
Asunto(s)
Alcaloides/química , Antibióticos Antineoplásicos/química , Inhibidores Enzimáticos/química , Indenos/química , Piridinas , Sulfonamidas/química , Compuestos de Azufre , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos/farmacología , Hidrólisis , Indenos/farmacología , Isoleucina-ARNt Ligasa/antagonistas & inhibidores , Espectroscopía de Resonancia Magnética , Estructura Molecular , Streptomyces , Sulfonamidas/farmacologíaRESUMEN
Pertinent necropsy findings in a 5 1/2-year-old Scottish Highland steer with chronic intractable pneumonia and cough were limited to the pulmonary system. The accessory lobe of the lung was collapsed, scarred, and multifocally adhered to parietal pleura. A polypoid mass almost completely obstructed the lobar bronchus and protruded into the trachea; mucopurulent exudate distended more distal bronchi. Botryomycosis was diagnosed when histologic examination revealed pyogranulomatous pneumonia with eosinophilic granules and "club" formation surrounding colonies of gram-positive cocci. Staphylococcus aureus was cultured from the lung. Botryomycosis is an unusual response to infection with common bacteria and is characterized by pyogranulomatous inflammation with formation of eosinophilic granules surrounding colonies of gram-positive cocci or gram-negative bacilli. Among domestic species, staphylococcal botryomycosis is most common as a wound infection in horses or as mastitis in cows and sows. Pulmonary botryomycosis is rare in horses, humans, and guinea pigs and apparently has not been reported in cattle.
Asunto(s)
Enfermedades Pulmonares Fúngicas/veterinaria , Neumonía/veterinaria , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/aislamiento & purificación , Animales , Bovinos , Inflamación , Pulmón/microbiología , Pulmón/patología , Enfermedades Pulmonares Fúngicas/patología , Masculino , Neumonía/microbiología , Infecciones Estafilocócicas/patologíaRESUMEN
This study determined whether the immunoassay for cerebrospinal fluid 14-3-3 protein concentration was sensitive and specific in the diagnosis of naturally occurring clinical scrapie in sheep. Cerebrospinal fluid was collected from 9 sheep with the confirmed diagnosis of scrapie. Additionally, cerebrospinal fluid was collected from 13 clinically normal sheep, which originated from a closely monitored flock with no history of scrapie. Sensitivity and specificity were calculated using standard epidemiological methods. Cerebrospinal fluid immunoassay results did not differ significantly between positive and negative sheep. Test sensitivity varied from 0.55 to 0.66, depending on the choice of test endpoint. Test specificity varied from 0.30 to 0.77, depending on the choice of test endpoint. The 14-3-3 cerebrospinal fluid immunoassay appears to have no value in the diagnosis of clinical scrapie in sheep.
Asunto(s)
Inhibidores Enzimáticos/líquido cefalorraquídeo , Scrapie/diagnóstico , Tirosina 3-Monooxigenasa/líquido cefalorraquídeo , Proteínas 14-3-3 , Animales , Diagnóstico Diferencial , Reacciones Falso Negativas , Inmunoensayo/veterinaria , OvinosRESUMEN
The Cot-death Syndrome is an out-moded model which is bizarre and unique in medical history for it enables a certificate of cause of death to be issued only if no medical cause can be found. It rewards incompetence. Apart from being a placebo for bereaved parents and a lucrative source of research funds it is unsupportable, lethal nonsense and it must be discarded. There are studies which prove that most infant death and chronic infant illnesses are linked and are primarily associated with environmental stress. The infant death problem is not a medical problem except where the stress trauma is of medical origin. The N.E.S.T. (Non-disease Environmental Stress Trauma) perspective provides a model which has elements of causation, prediction and prevention. It requires that intense investigation be carried out in an unbiased manner that is not hindered by a convenience syndrome barrier to truth. Unfortunately twenty years of adherence to the medical profession's Cot-death Syndrome hoax has meant that the evidence pin-pointing specific, causative environmental stress factors has been denigrated and disregarded. This has permitted the asthma convenience syndrome to thrive. Still-birth or infant death that is not due to disease or inherited causation can only be caused by environment stress trauma. Identifying and preventing such stress trauma is the key to healthy birth and to avoiding infant death and chronic infant disorders.
Asunto(s)
Modelos Biológicos , Muerte Súbita del Lactante/etiología , Ambiente , Humanos , Lactante , Recién Nacido , Estrés Fisiológico/complicaciones , SíndromeRESUMEN
Wet nappies at night could cause infants at risk to die. Tyler first suspected this ten years ago when his head was jerked back from his infant son's cot by the pungent odour of ammonia gas. This theory is consistent with the full epidemiology of cot-death. Ammonia is an insidious poison which has a wide and varied range of effects on the respiratory and nervous systems according to concentration and length of exposure. At its mildest it irritates the tissues. In larger doses ammonia can cause pulmonary oedema and pneumonitis. It can also cause stenosis of affected organs. Its chief danger lies in its potential to disrupt oxygenation at every level throughout the body. Acute and chronic poisoning profiles indicate the possibility that numbers of infants reported as dying from gastro-intestinal or respiratory disease could have been ammonia poisoning victims. Predisposing factors, such as smoking during pregnancy, are shown to contribute to the vulnerability of the infant to ammonia poisoning. The theory provides the framework for the development of an effective programme of infant death prevention.
Asunto(s)
Amoníaco/envenenamiento , Muerte Súbita del Lactante/etiología , Amoníaco/orina , Humanos , Lactante , Recién NacidoRESUMEN
The ammonia factor theory of infant death causation shows how the known, deadly properties of this respiratory poison, potentially present at every infant's cot, are compatible with the known causative relationships found with "cot-death syndrome" infants. It also predicted and demonstrated that a causal relationship existed between cot-death infants and most other post neo-natal infant deaths. The ammonia factor theory is quite incompatible with the medical profession's "cot-death syndrome" model. A critical evaluation of the medical profession's "cot-death syndrome" model shows that it provides no predictive, causative, diagnostic, or preventative dimensions and is used by some of the medical profession as a tool of fear to extract research monies and by others in the profession to placate parents. The "cot-death syndrome" model is a definition of a non-reality and the antithesis of a scientific model. As a mathematical model it is impossible and is supported by statistical gerrymandering. It places diagnosed "cot-death syndrome" parents in legal jeopardy. Its correlation with the reality of infant death is staggeringly improbable. These features are in stark contrast with the ammonia factor theory of infant death causation. The ammonia factor theory shows that the overall infant death rate is preventable through a programme of welfare, as well as through educational, social and environmental improvements. The medically centred "cot-death syndrome" model is a useless, lethal fallacy. It is politically obstructive. It must be discarded.
Asunto(s)
Muerte Súbita del Lactante/etiología , Amoníaco/toxicidad , Humanos , Lactante , Bienestar del Lactante , Matemática , Modelos Biológicos , Muerte Súbita del Lactante/epidemiología , Muerte Súbita del Lactante/prevención & controlRESUMEN
The cerebrospinal fluid of a dog with necrotizing meningoencephalitis showed pleocytosis, produced mostly by large granular lymphocytes. The presence of such lymphocytes in the cerebrospinal fluid of dogs with neurological disease appears not to have been reported previously.
Asunto(s)
Enfermedades de los Perros/líquido cefalorraquídeo , Linfocitosis/veterinaria , Meningoencefalitis/veterinaria , Animales , Perros , Femenino , Subgrupos Linfocitarios , Linfocitosis/líquido cefalorraquídeo , Meningoencefalitis/líquido cefalorraquídeoRESUMEN
Eperythrozoon organisms were isolated from the blood of a young beef bull with scrotal and hindlimb edema. Young beef bulls, managed under conditions closely mimicking those used in organized bull testing programs, were experimentally administered eperythrozoon organisms. Scant to few organisms were identified on blood smears from bulls (5 of 6) for 2 to 4 days starting 12 days after administration. After a second challenge with intravenously administered viable eperythrozoon organisms, the bulls demonstrated immunity by either failing to become parasitemic (4 of 6) or rapidly clearing the organisms from the blood (2 of 6). No bull became anemic, icteric, or hypoglycemic. Increased serum lactate and decreased blood bicarbonate concentrations probably reflected increased glycolytic activity of infected erythrocytes. A cause for azotemia observed late in the study was not determined. The bulls did not develop scrotal or hindlimb edema. Scrotal circumference and texture remained constant throughout the study. Semen quality was minimally altered while the bulls had organisms identified on blood smears. Harsh lung sounds were asculted in bulls during and immediately after organisms were present in the blood. Although the bulls reliably had organisms in the blood, none showed anemia, scrotal or hindlimb edema, or decreased semen quality; therefore, an additional factor or factors, or greater parasite load may be required for the expression of disease.
RESUMEN
Young (9 to 10 mo) Aberdeen-Angus bulls (n = 5) in excellent body condition and pastured with approximately 35 other bulls of similar age on a farm in southeastern Alabama had fever, harsh pulmonary sounds, increased respiratory rate and variable amounts of hindlimb and scrotal edema. Bulls had mild microcytic, normochromic anemia. Numerous eperythrozoon organisms were identified on blood smears. Indirect hemagglutination inhibition test results for Eperythrozoon suis antibodies were negative either because E. suis antigens do not cross react with cattle eperythrozoon organism antibodies or blood was collected before there was sufficient time for seroconversion. Bulls had swelling of the scrotal wall, soft testes, and poor semen quality, characterized by low progressive motility and a high percentage of spermatozoa with primary and secondary abnormalities. Some of these abnormalities may be attributed to the age of the bulls. However, loss of scrotal thermoregulation was a major cause of testicular degeneration leading to poor semen quality. Other bulls in the herd had fever, increased respiratory rate, and swollen hindlimbs or scrotum. Subsequent to administration of oxytetracycline, parasitemia resolved rapidly, and clinical signs gradually abated. Four of five bulls successfully passed breeding soundness examinations six months after initial clinical illness. The remaining bull failed twice due to the presence of testicular inflammation.
RESUMEN
Nuclear bone scintigraphy was used to diagnose sacroiliac injury in 12 horses presented for nonspecific rear limb lameness. The most common history was decreased performance and/or a mild chronic rear limb lameness which could not be localised by routine lameness examination. The scintigraphic patterns of the 12 affected horses were compared to 5 normal horses and 10 horses with lameness not related to the pelvic region. Subjective and quantitative evaluation of the bone scans clearly separated the 12 affected horses from the 5 normal horses and the 10 horses with lameness from causes other than the sacroiliac joint disease. The 12 affected horses had a scintigraphic pattern of moderate to marked increased uptake of the radiopharmaceutical within the sacroiliac joint region on the side of lameness. In contrast, the 5 normal horses and 10 horses scanned for other causes of lameness, had a symmetric, or only slightly asymmetric pattern of radioisotope uptake. Although nonspecific for the type of injury, nuclear bone scintigraphy is considered sensitive for the detection of sacroiliac injuries in horses.
Asunto(s)
Caballos/lesiones , Vértebras Lumbares/diagnóstico por imagen , Articulación Sacroiliaca/lesiones , Sacro/diagnóstico por imagen , Factores de Edad , Animales , Dolor de Espalda/diagnóstico por imagen , Dolor de Espalda/veterinaria , Femenino , Estudios de Seguimiento , Marcha , Cojera Animal/diagnóstico por imagen , Masculino , Palpación/veterinaria , Cintigrafía , Estudios Retrospectivos , Articulación Sacroiliaca/diagnóstico por imagen , Heridas y Lesiones/diagnóstico por imagen , Heridas y Lesiones/veterinariaRESUMEN
Increased pulmonary arterial pressures as a result of pulmonary disease are described in two cows with chronic pneumonia and one cow with acute pneumonia. Based on clinical signs of congestive right heart failure, increased pulmonary arterial pressure, and right ventricular hypertrophy, cor pulmonale was diagnosed in one cow. Two cows had increased pulmonary arterial pressure and signs of right heart insufficiency, but right ventricular hypertrophy was not identified. Two of the cows had ventral edema and exercise intolerance. All cows had jugular venous distention and increased right atrial and pulmonary arterial pressures. Peripheral arterial PaO2 was decreased in two cows, and not measured in the third cow. Although an uncommon cause of congestive heart failure in cattle at low altitudes, pulmonary hypertension should be considered in cattle with clinical right heart failure.