Venous blood pressure relative to the development of bovine udder edema

Cranial superficial epigastric (milk vein) and jugular venous blood pressure were measured in 8 cows with udder edema and in 3 normal control cows at least 2 weeks before parturition, at parturition, and 2 weeks after parturition. Cows with udder edema had a significant mean increase (P less than or equal to 0.05) in cranial superficial epigastric venous pressure at parturition when compared with pressures 2 weeks prepartum and 2 weeks postpartum. Unaffected control cows had an insignificant increase in cranial superficial epigastric venous pressure during these 3 periods of measurement. There was an insignificant increase in jugular venous blood pressure during the 3 periods of measurement in affected and control cows. A correlation was observed between mammary blood flow and cranial superficial epigastric blood pressure at parturition (r = -0.659, P less than or equal to 0.05).     

Blood flow parameters associated with udder oedema in Jersey cattle affected with rectovaginal constriction

Udder oedema was studied in eight Jersey cows with rectovaginal constriction (RVC) and three normal Jersey cows. A complete physical examination was performed at least two weeks before parturition, at parturition and two weeks after parturition. Jersey cows with RVC developed udder oedema as early as 14 days before parturition, and condition persisted for three to 10 days following parturition. Mammary blood flow and cranial superficial epigastric venous blood pressure were measured in three Jersey cows with RVC with udder oedema and three normal Jersey cows. The former with udder oedema had a significant decrease in mammary blood flow at parturition compared to the normal Jersey cows (P less than 0.05); there was no significant difference in mammary blood flow between Jersey cows with RVC and normal Jersey cows two weeks before parturition (P greater than 0.05). A significant mean increase in cranial superficial epigastric venous blood pressure occurred at parturition when compared to two weeks before parturition in Jersey cows with RVC (P less than 0.05), but normal Jersey cows had no significant increase in cranial superficial epigastric vein pressure during these two periods of measurement (P greater than 0.05). There was no significant increase in jugular vein blood pressure during the two periods of measurement in Jersey cows with RVC or normal Jersey cows (P greater than 0.05). There was a significant negative correlation between mammary blood flow and cranial superficial epigastric pressure at parturition (r = 0.733, P less than 0.05).     

The Mammary Blood Flow in the Cow as Measured by the Antipyrine Absorption Method

After intramammary application of 3 g antipyrine dissolved in 30 ml distilled water into each quarter the absorption of antipyrine from the udder proceeds as a first order reaction. As the injected amount is known as well as the amount of antipyrine milked out about 1 hour later can be determined, it is possible to calculate the amount absorbed at any time between injection and emptying.It is shown, that the concentrations of antipyrine in the blood from the jugular vein and external pudic artery are identical after intramammary application of antipyrine. In experiments on lateral recumbent cows it is shown that the venous blood returns from the udder via both the subcutaneous abdominal and the external pudic veins. In the standing cows blood samples were drawn from the jugular and the subcutaneous abdominal veins. The blood samples from the subcutaneous abdominal veins were drawn during manual compression of the external pudic veins to get representative concentrations of antipyrine in the total venous blood from the udder. On account of the amount of antipyrine absorbed and the difference in antipyrine concentrations between the subcutaneous abdominal veins and the jugular vein the mammary blood flow in lactating cows was found to vary between 22–101 ml/min. per 100 g gland tissue.The possibility of calculating the mammary blood flow after injection in two glands only — while the two remaining glands might be used for other studies — is shown and discussed. The influence of the individual differences in the venous anastomoses on the results is discussed, and a procedure is described to select cows suitable for experiments on mammary blood flow.     

Mammary secretion of oestrogens in the cow

Two experiments in vivo and one experiment in vitro were conduced to examine the mechanisms involved, which lead to mammary secretion of oestrogens and its importance for milk production and udder health in cows. In experiment 1 in six cows of the White-Black breed on day 268 of pregnancy catheters were inserted into uterine vein of pregnant horn, the abdominal aorta and the caudal superficial epigastric (milk) vein. Blood samples for estimation of oestrone, oestrone sulphate, oestradiol-17alpha and -17beta by RIA were obtained daily from day 7 pre-partum until day 1 post-partum. Only the concentration of oestradiol-17beta was statistically higher (P< or =0.01) in mammary venous plasma than in aortal and uterine plasma. In experiment 2 forty late-pregnant cows were divided into two groups according to their milk production in the previous lactation: group 1 (n=20) high-yielding cows (>6500kg milk per lactation), and group 2 (n=20) low-yielding cows (<3700kg milk per lactation). Blood samples for measurement of oestradiol-17beta by RIA were collected from milk and tail veins every fourth day during a period from day 20 prior to parturition to day 4 post-partum. The concentration of oestradiol-17beta was significantly higher (P< or =0.01) in the milk vein than in the peripheral plasma from day 12 pre-partum to parturition. In high-yielding cows the level of oestradiol-17beta in mammary venous blood was significantly higher (P< or =0.01) than in low-yielding cows. In six cows with pathological udder oedema ante-partum the concentration of oestradiol-17beta in milk vein was significantly higher (P< or =0.05) than in control cows. There were no statistically significant differences in the levels of oestradiol-17beta in cows with clinical mastitis (n=10) during 2 weeks after parturition and without it (P> or =0.05). In an in vitro experiment, homogenates of mammary tissue collected on day 7 pre-partum from two cows were incubated with 3H-androstendione. After incubation the samples were extracted and 3H-oestradiol-17beta was separated by HPLC. 3H-oestradiol-17beta was formed in a total yield of 37%. These results indicate that oestrone, oestrone sulphate and oestradiol-17alpha are not secreted by bovine mammary gland. Furthermore, the secretion of oestradiol-17beta starts about day 12 pre-partum and is associated with milk yield and udder oedema. Preliminary in vitro study suggests the synthesis of oestradiol-17beta by mammary tissue.     

Udder edema in cattle: effects of diuretics (furosemide, hydrochlorothiazide, acetazolamide, and 50% dextrose) on serum and urine electrolytes

Blood and urine chemical values at parturition in clinically normal Holstein cows (n = 12) were compared with the same values in Holstein cows developing udder edema (n = 12). There was no statistically significant mean difference between the 2 groups for the serum and urine chemical data. Furosemide (500 mg) given IV caused a significant increase in serum calcium and sodium, urine chloride, potassium, and sodium, and fractional excretional ratio of chloride, potassium, and sodium. There was a significant mean decrease in the serum potassium, urine creatinine, osmolality, pH, and specific gravity. Hydrochlorothiazide (250 mg) given IV caused a significant mean increase in serum chloride, urine chloride, potassium, and sodium, and fractional excretion ratio of chloride, potassium, and sodium. There was a significant mean decrease in serum potassium and sodium, urine osmolality, pH, and specific gravity. Acetazolamide (500 mg) given IV caused a significant mean increase in blood urea nitrogen, serum chloride and glucose, urine sodium, and fractional excretion ratio of sodium, while causing a significant mean decrease in serum potassium, sodium, and phosphorus, and urine creatinine. Dextrose (500 g) given IV as a 50% solution caused a statistical mean increase in serum glucose, urine chloride, potassium, and sodium, and fractional excretion ratio of chloride and potassium. A statistical mean decrease occurred in the packed cell volume, blood urea nitrogen, serum calcium, potassium, sodium, and phosphorus, urine creatinine, osmolality, and pH.     

Mammary blood flow and venous drainage in cows

The mammary blood flow and the udder drainage in vivo evaluated using the antipyrine absorption method has been compared with the anatomical findings in the udder after slaughtering of the experimental cows (Table 1).Because of the orientation of the valves in the perineal veins and blood samples taken in vivo it must be assumed that the perineal veins lead blood toward the veins at the udder base.It is concluded that the drainage of the udder in standing cows will primarily be through the milk veins, eventually there will be a flow of non-mammary venous blood down the external pudic veins at the udder base, as in the case of the perineal veins.     

Risk factors for udder edema and its association with lactation performance on primiparous Holstein cows in a large Florida herd, U.S.A

The objective of this study was to determine risk factors for udder edema (case–control study) and to evaluate the association of udder edema in primiparous Holstein cows with their lactation performance (cohort study). Values for the first 10 test day for milk yield, fat, protein, and somatic cell counts (SCC) linear score as well as mature equivalent (ME) 305 days milk yield, fat, protein, SCC linear score, and incidences of periparturient diseases from a computerized farm recording system were compared between primiparous cows with and without udder edema. Data consisted of 118 dairy heifers with udder edema, induced for parturition, and treated with diuretics and 889 control heifers that received no treatment. Primiparous cows giving birth to male calves, were 1.72 (1.01, 3.24; 95% CI) times more likely to develop udder edema than cows giving birth to female calves. Primiparous cows calving in winter season were 3.68 (1.09, 12.5; 95% CI) times more likely to develop udder edema than cows calving in summer. For each extra 10 cm in height the odds of udder edemas was 1.23 (1.03, 1.47; 95% CI). The first test day DHIA milk yield was lower in cows that developed udder edema (3.6 kg/day) than in normal cows. However, the subsequent test days and ME measurements were not statistically different between groups. Cows with udder edema were 1.62 (1.18, 2.14; 95% CI) times more likely to develop udder edema in the second lactation than control animals. It is concluded that the gender of the offspring, calving season and height at parturition were significant risk factors for udder edema. Only milk yield on the first DHIA test day was lower in cows with udder edema than in cows without udder edema.     

Life-threatening injuries of the subcutaneous ventral abdominal veins in dairy cows

Injuries of the superficial veins on the ventral abdomen of dairy cows can result in life-threatening haemorrhage. Treatment of these injuries can be difficult because of the characteristics of the veins. Five cows aged 6.5 to 12 years were referred to the Animal Hospitale Zurich, because of intermittent haemorrhage from a ventral abdominal vein. Four of the cows were near term and one had calved two weeks before referral. Intermittent bleeding was seen from the highly convoluted and dilated subcutaneous tributaries to the cranial superficial epigastric vein (milk vein). The haematocrit of 2 cows was markedly lower than normal. Emergency slaughter of one of the cows was carried out because of advanced age. The other 4 cows were sedated and after application of local anaesthetic, the wounds were debrided and sutured. Two of the cows required a blood transfusion before being operated. There were no postoperative complications. This type of injury seems to occur predominantly in pluriparous dairy cows close to term, in which the tributaries to the milk vein have undergone varicose changes. Treatment should consist of surgical resection of the injured tissue and suturing of the venous wall, subcutaneous tissues and skin.     

Cardiopulmonary effects of continuous intravenous infusion of guaifenesin, ketamine, and xylazine in ponies

Eight ponies were anesthetized with a solution containing 50 mg of guaifenesin, 1 mg of ketamine, and 0.5 mg of xylazine X ml-1 of 5% dextrose in water. Anesthesia was induced by IV injection (1.1 ml X kg-1), followed by continuous IV infusion at 2.75 ml X kg-1 X hr-1. Heart rate, rate-pressure product, mean pulmonary artery pressure, and standard bicarbonate were not significantly changed throughout the study. Systolic, diastolic, and mean arterial pressures and left ventricular stroke work index were significantly decreased at 5 and 15 minutes after a bolus of the anesthetic solution was injected. Systolic blood pressure returned to within the base-line range at 30 minutes, but diastolic and mean arterial pressures were significantly decreased throughout the study. Cardiac index and arterial pH were decreased at 5 minutes only. Systemic vascular resistance was significantly decreased 60 minutes after bolus injection was given. Hypoventilation, as indicated by increased PaCO2, occurred 5 minutes after bolus injection was given.     

Treatment of cardiovascular disease in cattle.

Cardiac diseases of cattle may involve valvular structures, myocardium, pericardium, or blood vessels and are manifested by the clinical signs of cardiac dysrhythmias, cardiac murmurs, generalized edema, muffled heart sounds, jugular venous distention, jugular venous pulsations, pulmonary edema, pleural effusion, or ascites. Digoxin, quinidine, and furosemide can be used effectively to control signs of CHF and cardiac arrhythmias. Combination antimicrobial therapy can be successful for cows with infective endocarditis and thrombophlebitis. Pericardial fluid drainage may temporarily improve cattle with traumatic pericarditis or lymphosarcoma so that short-term goals may be reached.     

Effect of xylazine on cerebrospinal fluid pressure in conscious horses.

Lumbosacral CSF pressure was measured in 6 horses via a catheter inserted through the lumbosacral space. Heart rate, facial artery pressure, central venous pressure, and CSF pressure were measured before IV injection of a saline solution control, for 15 minutes after saline solution injection, and for 60 minutes after the IV injection of 1.1 mg of xylazine/kg of body weight. Arterial pH and blood gases were analyzed before saline solution injection, 15 minutes after saline solution injection, and at 15, 30, and 60 minutes after xylazine injection. Constant craniocervical posture was maintained during sedation. Lumbosacral CSF pressure was significantly decreased for 15 minutes after xylazine injection. Diastolic arterial pressure was significantly increased 4 minutes after xylazine administration and diastolic and mean arterial pressure were increased at 6 and 8 minutes after xylazine administration. Small increases in systolic arterial blood pressure and central venous pressure, and a small decrease in heart rate were observed. There were no significant differences in the arterial blood gas values. It was concluded that IV injection of xylazine causes a decrease in intracranial pressure in healthy conscious horses. The effects may be different in horses with neurologic disease or cerebral trauma.     

Effects of butorphanol, flunixin, levorphanol, morphine, and xylazine in ponies

The analgesic and behavioral effects of butorphanol (0.22 mg/kg), flunixin (2.2 mg/kg), levorphanol (0.033 mg/kg), morphine (0.66 mg/kg), and xylazine (2.2 mg/kg), given IM were observed in 8 ponies. These ponies were instrumented to measure response objectively to painful superficial and visceral stimuli. Effects on the cardiopulmonary system and rectal temperature also were evaluated in 6 of these ponies. Observations were conducted before drug injection (base-line values) and after injection at 30, 60, 120, 180, and 240 minutes. Xylazine provided the highest pain threshold for the first 60 minutes and a sedative effect for 105 minutes. The effects for superficial pain and visceral pain persisted 3 hours and 4 hours, respectively. Morphine produced good analgesia for superficial pain (30 minutes), whereas butorphanol provided good effect for visceral pain (4 hours). A slight degree of analgesia for visceral pain was obtained after morphine (1 hour) and levorphanol (4 hours); flunixin did not induce analgesia. Butorphanol, levorphanol, and morphine stimulated motor activity. Behavioral effects did not occur after flunixin was given. Xylazine decreased systolic, diastolic, and mean blood pressures. Marked increases in these pressures, heart rate, and respiratory rate were observed after morphine was given. Changes of central venous pressure, rectal temperature, and blood gas values remained within base-line limits after both drugs were given. Butorphanol increased heart rates for 1 hour; flunixin and levorphanol did not alter any of the above values.     

Ultrasonographic findings in a cow with ascites due to thrombosis of the caudal vena cava.

This case report describes a three-year-old Swiss Braunvieh cow with ascites due to thrombosis of the caudal vena cava. Ultrasonography verified the ascites and revealed dilatation of the abdominal portion of the caudal vena cava (4.8 cm). It was presumed that the caudal vena cava was occluded by a thrombus or by perivenous compression cranial to the dilatation. Post mortem findings included: a massive accumulation of fluid in the abdominal cavity; a 15 cm long thrombus in the subphrenic region of the caudal vena cava; multiple pulmonary abscesses; severe thrombosis of the pulmonary vasculature; hepatic congestion; oedematous abomasal folds; and severe thrombophlebitis of the left jugular vein and both udder veins, due to poor intravenous injection technique. Ascites caused by thrombosis of the caudal vena cava is rare because collateral routes of venous return, including the udder veins, are usually established. It was therefore concluded that the ascites was attributable to bilateral thrombosis of the udder veins.     

Evaluation of the Cranial Rectus Abdominus Muscle Pedicle Flap as a Blood Supply for the Caudal Superficial Epigastric Skin Flap in Dogs

This study evaluates the cranial rectus abdominus muscle pedicle flap as the sole blood supply for the caudal superficial epigastric skin flap. This flap was composed of a cranially based rectus abdominus muscle pedicle flap that was attached to the caudal superficial epigastric island skin flap (including mammary glands 2 to 5) via the pudendoepigastric trunk. Selective angiography of the cranial epigastric artery in eight cadaver dogs proved that the arterial vasculature in the cranial rectus abdominus was contiguous with that in the caudal superficial epigastric skin flap. In the live dog study, three of six of the flaps failed because of venous insufficiency. Necrosis of mammary gland 2 occurred in two of six flaps. One of six flaps survived with the exception of the cranial most aspect of mammary gland 2. Angiography of the cranial epigastric artery proved that arterial blood supply to these flaps was intact. Histological evaluation of the failed flaps showed full-thickness necrosis of the skin and subcutaneous tissues, the presence of severe congestion, and venous thrombosis. Retrograde venous blood flow through the flap was inconsistent, and hence resulted in failure of this myocutaneous flap. Use of this flap for clinical wound reconstruction cannot be recommended.     

Udder edema: biochemical studies in Holstein cattle

Udder edema was studied in 9 affected and 3 control Holstein cows ranging in age from 2.5 to 8 years. A complete physical examination was done in conjunction with serum analysis for total protein, albumin, globulin, sodium, potassium, chloride, calcium, and inorganic phosphorus 2 weeks before parturition, at parturition and 2 weeks following parturition. Mammary interstitial fluid samples also were obtained from cows with udder edema and analyzed for total protein, albumin, globulin, sodium, potassium, chloride, calcium, and inorganic phosphorus. Clinical signs of udder edema appeared as early as 7 days prepartum and persisted for as long as 9 days postpartum. There were no significant differences in serum constituents between affected and control cows at the same stage of pregnancy or lactation. There was a significant difference (P less than or equal to 0.05) between serum and mammary interstitial fluid in the total protein, albumin, globulin and calcium concentrations.     

Pulmonary Hypertension and Cardiac lnsuff iciency in Three Cows with Primary Lung Disease

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.     

Hemodynamic response of calves to tiletamine-zolazepam-xylazine anesthesia.

Six healthy Holstein calves were anesthesized with isoflurane in O2 and instrumented for hemodynamic studies. A saphenous artery was catheterized for measurement of blood pressure and withdrawal of blood for determination of the partial pressure of carbon dioxide (PaCO2), oxygen (PaO2), and arterial pH (pHa). Respiration was controlled throughout the study. The ECG and EEG were monitored continuously. A thermodilution catheter was passed via the right jugular vein into the pulmonary artery for determination of cardiac output and measurement of central venous pressure, pulmonary arterial pressure, and pulmonary capillary wedge pressure. Baseline values (time 0) were recorded following recovery from isoflurane. Tiletamine-zolazepam (4 mg/kg)-xylazine (0.1 mg/kg) were administered IV immediately after recording baseline values. Values were again recorded at 5, 10, 20, 30, 40, 50, and 60 minutes after injection. Changes in left ventricular stroke work index, PaCO2, and pHa were insignificant. Arterial blood pressure and systemic vascular resistance increased above baseline at 5 minutes and then gradually decreased below baseline at 40 minutes, demonstrating a biphasic response. Values for pulmonary capillary wedge pressure, pulmonary arterial pressure, central venous pressure, and PaO2 were increased above baseline from 5 to 60 minutes. Stroke volume, stroke index, and right ventricular stroke work index were increased from 20 or 30 minutes to 60 minutes. Pulmonary vascular resistance increased at 10 minutes, returned to baseline at 20 minutes, and was increased again at 60 minutes. Heart rate, cardiac output, cardiac index, and rate pressure product were decreased at 5 minutes, and with the exception of cardiac output, remained so for 60 minutes. Cardiac output returned to the baseline value at 30 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Oxymorphone: cardiovascular, pulmonary, and behavioral effects in dogs

Cardiovascular, pulmonary, and behavioral effects of multiple doses of oxymorphone in 10 nonanesthetized, spontaneously breathing, healthy dogs were studied. Oxymorphone (0.4 mg/kg of body weight) was administered IV, and at 20, 40, and 60 minutes after the first injection was given, 0.2 mg of oxymorphone/kg was administered. Cardiovascular and pulmonary variables were measured before (base line) and at 5, 15, 35, 55, 75, 100, 120, 150, 180, 210, 240, 270, and 300 minutes after the first oxymorphone injection. Degree of sedation and behavioral effects also were recorded. Naloxone (0.04 mg/kg, IV) was administered 4.5 hours after the 4th oxymorphone injection, and behavioral changes were recorded. Oxymorphone induced mild respiratory depression. After transient apnea developed, respiratory rate increased to a pant, tidal volume decreased, and minute ventilation increased, but these values were not significantly (P = 0.05) different from base line. The PaCO2, physiologic dead space, and base deficit increased; alveolar tidal volume decreased; and alveolar minute ventilation did not change. The PaO2 decreased, hemoglobin and arterial O2 content increased, and O2 transport did not change. Venous admixture transiently increased. Oxymorphone induced minimal cardiovascular depression. Mean arterial blood pressure, stroke volume, central venous pressure, pulmonary artery pressure, and pulmonary wedge pressure increased. Heart rate decreased, systemic vascular resistance transiently increased, and cardiac output transiently decreased. Because the dogs moved spontaneously, responded to sound with sudden, vigorous movements, and breathed with excessive effort, oxymorphone alone was considered inadequate as a general anesthetic.     

Cardiopulmonary effects of a medetomidine-ketamine combination administered intravenously in gopher tortoises

OBJECTIVE: To determine whether IV administration of a combination of medetomidine and ketamine depresses cardiopulmonary function in healthy adult gopher tortoises. DESIGN: Prospective study. ANIMALS: 3 adult male and 3 adult female nonreleasable gopher tortoises. PROCEDURE: Prior to the study, carotid and jugular catheters were surgically placed in each tortoise for blood collection, direct arterial blood pressure monitoring, and drug administration. Heart rate, direct carotid arterial blood pressure, and body temperature were measured before and every 5 minutes for 45 minutes after IV injection of medetomidine (100 microg/kg [45.5 microg/lb]) and ketamine (5 mg/kg [2.3 mg/lb]). Carotid arterial blood samples were collected before and 5, 15, 30, and 45 minutes after medetomidine-ketamine administration to determine pH, PO2, and PCO2. Atipamezole (500 mg/kg [227 microg/lb], IV) was administered 30 minutes after administration of medetomidine-ketamine. RESULTS: The medetomidine-ketamine combination caused a moderate increase in arterial blood pressure, and moderate hypercapnia and hypoxemia. There were no significant changes in heart rate or body temperature. Intravenous administration of atipamezole rapidly induced severe hypotension. CONCLUSIONS AND CLINICAL RELEVANCE: The combination of medetomidine and ketamine administered IV resulted in effective short-term immobilization adequate for minor diagnostic procedures in gopher tortoises. This combination also caused moderate hypoventilation, and it is recommended that a supplemental source of oxygen or assisted ventilation be provided. Atipamezole administration hastens recovery from chemical immobilization but induces severe hypotension. It is recommended that atipamezole not be administered IV for reversal of medetomidine in tortoises and turtles.