Legends for Video Clips

Legends for Video Clips To view videos go to: http://dairydiseases.vet.cornell.edu/ Video clip 2.1 A 1-day-old Holstein heifer became distressed with pronounced salivation after feeding of colostrum through an esophageal feeder. When the feeder tube was removed from the calf ’s mouth, it was noted that a large part of the tube was missing. Endoscopic findings: Endoscopic retrieval of the broken esophageal feeder lodged in the esophagus of the calf. This feeder had been used for several months on numerous calves with bleach disinfection between use before breaking and becoming trapped in the esophagus of this calf. Diagnosis: Esophageal obstruction with broken esophageal feeder. Video clip 2.2 Demonstration of collection of cerebrospinal fluid from the lumbosacral space in cattle. Video clip 3.1 An adult Holstein cow with persistent fever and weight loss. Technique for establishing true retrograde filling of the jugular vein associated with right heart failure: The vessel is held off close to the ramus of the mandible, “emptied” by running two fingers down the vein toward the thoracic inlet, and then allowed to “backfill” from the brisket. Ensure that the head is in a neutral position and not held lower than the base of the heart. The animal in this video had severe vegetative endocarditis involving the right atrioventricular valve. Diagnosis: Vegetative endocarditis and right heart failure. Video clip 3.2 A 5-year-old Holstein cow with anorexia, tachycardia, and irregular rhythm of the heart noted during auscultation. Note the rapid “hosepipe”-like filling of the jugular vein from the thoracic inlet to the mandible with the head held in a neutral position. Persistent jugular distension is also evident, as is the arrhythmic nature of the pulse waves. This demonstrates true jugular pulsation associated with right sided heart failure. Diagnosis: Cardiac lymphosarcoma involving the right atrium. Video clip 3.3 and heart rates.

A 7-day-old calf with increased respiratory

Echocardiographic findings: Doppler flow echocardiogram of 7-day-old Holstein calf with a ventricular septal defect, demonstrating flow across the defect high in the interventricular septum, a classic location for this congenital abnormality. (Courtesy of Dr. Heidi Kellihan.) Diagnosis: Ventricular septal defect. Video clip 3.4

A 14-day-old calf with decreased vigor.

Echocardiographic findings: Doppler flow echocardiogram

demonstrating flow across the atria. (Courtesy of Dr. Rebecca Stepien.)  Diagnosis: Atrial septal defect.

Video clip 3.5 A 4-year-old Holstein cow with anorexia, decreased milk production for the past 3 days, “bottle jaw”, enlarged (pipelike) jugular veins, muffled heart sounds, and severe tachycardia (140 beats/min). Pericardiocentesis: Pericardial effusion was noted on ultrasound examination, and a right-sided pericardiocentesis was performed; 3 L of hemorrhagic fluid was removed. Cytologic examination of the fluid revealed 3,700 white blood cells/μL with 21% neutrophils, 32% macrophages, 36% lymphocytes, and 6% eosinophils. There were large numbers of red blood cells in the fluid, evidence of macrophage erythrophagia, and the total protein was 5.5 g/ dL. No neoplastic cells were seen, and the cow was bovine leukemia virus negative. The cow was anemic (hematocrit; 21%) before the procedure, and the hematocrit increased to 32% 5 days later. The cow also had a mild thrombocytopenia (120,000/μL) before pericardiocentesis which increased to greater than 400,000/μL 48 hours after the procedure. The cow’s clinical signs resolved within 36 hours. After pericardial drainage, her milk production increased, and she was still healthy 2 years later.  Diagnosis: Idiopathic hemorrhagic and inflammatory pericarditis. Video clip 3.6 A 3-year-old cow with a 5-day history of poor appetite, decreased rumen contractions, and a sudden drop in milk production. Fever was intermittently present. Pericardiotomy: Left-sided pericardiotomy being performed in a 3-year-old cow with septic pericarditis caused by “hardware.” After incising the pericardium, fetid-smelling yellow fluid was discharged in a projectile manner from the pericardium. The prognosis for similarly affected cattle is poor. Diagnosis: Traumatic reticulopericarditis; septic pericarditis. Video clip 3.7 A 5-year-old Holstein cow with fever, decreased production, and muffled heart sounds. Echocardiographic findings: Note the large volume of anechoic pericardial fluid in which the heart “floats” and the fibrin fronds attached to the epicardial surface. The effusion was reported to be non-neoplastic at the time these images were obtained but transitioned to a lymphoblastic effusion over a 9-month period.  Diagnosis: Idiopathic hemorrhagic pericardial effusion initially.  Final diagnosis: Lymphosarcoma (pericardial). Video clip 4.1 A 9-month-old Holstein heifer was examined because of stertorous breathing since birth. The difficulty in breathing was accentuated by increased environmental temperature. The heifer was otherwise healthy. Endoscopy findings: The initial part of the video shows the normally large nasopharyngeal septum, but in the distance, a normal size opening to the nasopharynx cannot be seen. The larynx appears 807

808

Legends for Video Clips

normal, but as the scope is withdrawn away from the larynx or advanced toward the larynx, a collapse of the pharyngeal wall is noted. A diagnosis of functional pharyngeal collapse was made. The heifer’s respiratory signs have remained unchanged, but she calved normally 1 year later. The owner reported she is smaller than other 2-year-olds on the farm, and she moves slower than the other cows in the summer months.  Diagnosis: Pharyngeal collapse.

Endoscopy findings: A mass is observed on the right ventricle of the larynx. This mass was incised (last segment of the video), and thick mucus material was drained. A biopsy and histopathology of the wall of the mass suggested this was a branchial cyst. After general anesthesia, the lining of the cyst was removed by laser surgery. The cow recovered and has remained normal without any respiratory noise.  Diagnosis: Laryngeal cyst.

Video clip 4.2 A 2-month-old Holstein bull calf with a 3-week history of progressive dyspnea and upper respiratory stridor. Endoscopy findings: Swelling of arytenoid cartilages and exudate draining from the left arytenoid area can be seen. A tracheostomy was performed followed by surgical exploration under general anesthesia. The dorsal portion of the left arytenoid cartilage was necrotic and draining pus. The necrotic area was curetted (not shown in video), and the calf was treated with penicillin. The calf had a complete recovery.  Diagnosis: Necrotic laryngitis.

Video clip 4.7A A 7-week-old Holstein heifer with a temporary tracheostomy in place for relief of severe upper respiratory stridor caused by necrotic laryngitis. Video was obtained within 4 hours of the procedure, and the marked difference in comfort and respiratory rate and effort was evident. Medical treatment was only partially successful, and the calf eventually underwent a permanent tracheolaryngotomy. Diagnosis: Necrotic laryngitis.

Video clip 4.3 A 2-month-old Holstein heifer was examined because of a 1-month history of progressive respiratory distress with stridor. Tilmicosin, dexamethasone, and flunixin meglumine had been used as treatments but had not been effective. Endoscopy findings: There is evidence of laryngitis, severe edema of the trachea and larynx, and deformity of the right arytenoid cartilage. A tracheostomy was performed as an emergency procedure and surgery was recommended. The owners declined, and the calf was euthanized.  Diagnosis (necropsy): Chronic necrosuppurative laryngitis, tracheitis, and pneumonia. Video clip 4.4 An adult Holstein cow with a 5-day history of upper respiratory stridor. There had been some transient improvement in the clinical signs after a combination of corticosteroid and antimicrobial therapy. Endoscopy findings: (Pre-operative) An inflamed larynx with little movement of the arytenoid cartilages can be noted. A mass can be seen caudal and dorsal to the cartilages. ­After a t­ racheostomy, the abscess and the diseased arytenoid cartilage were surgically removed. Three days later on recheck, endoscopy (Post-operative) revealed significant improvement in laryngeal function. The cow was treated with penicillin for 2 weeks and received a single dose of dexamethasone immediately after surgery. The cow recovered and was healthy at a 6-month follow-up.  Diagnosis: Trueperella pyogenes arytenoid abscess. Video clip 4.5 A 9-year-old Brown Swiss cow with a 2-week history of fever and coughing with sudden progression to respiratory distress with stridor. Endoscopy findings: Evidence of arytenoid chondritis that nearly obstructs the airways. A tracheostomy was performed, and, under local anesthetic, the necrotic left arytenoid was grasped and removed. The cow was treated with ceftiofur, penicillin, and flunixin and was doing well at 6-month follow-up.  Diagnosis: Necrotic arytenoid chondritis. Video clip 4.6 A 2-year-old Holstein cow that had made an audible upper respiratory noise since shortly after birth. The noise had become louder over time and was beginning to cause some respiratory distress.

Video clip 4.7B A 4-month-old Holstein calf with progressive respiratory noise and cough that presented in respiratory distress. A tracheostomy had to be performed because of the severity of the airway obstruction. A laryngotomy and partial arytenoidectomy were performed 2 days later, and the calf made a complete recovery. Diagnosis: Necrotic laryngitis. Video clip 4.8 A 1-month-old calf with chronic cough, increased respiratory rate, and nasal discharge. Ultrasound findings: Toward the end of the clip, note the “hepatized” appearance to the lung indicative of lobar consolidation. Diagnosis: Chronic bronchopneumonia. Video clip 4.9 A, A 3-month-old Holstein heifer with severe pneumonia and respiratory distress. The calf had been treated on the farm for 2 weeks with various macrolide antibiotics, enrofloxacin, and ceftiofur with no clinical response. B, The same calf as in A after 2 weeks of hospitalization, intranasal oxygen therapy, nebulization for a week, and daily administration of oxytetracycline intravenously every 12 hours and procaine penicillin subcutaneously every 12 hours. Diagnosis: Bronchopneumonia; marked improvement. Video clip 4.10 An 8-year-old Holstein cow with recurrent fevers and cough after calving 1 week earlier. Ultrasound findings: A vector 4- to 1-MHz scan head is used. Ventral is to the left side of the image. The pleural space contains large abscesses; these are the two compartments of fluid with waving tags of fibrin, 5 cm and 18 cm in diameter, with distinct 1-cm thick capsules. The lung is poorly visualized as the dorsal (right side of the image), triangular, hyperechoic structure at 5 to 10 cm depth. The lung is adhered to the pleural abscesses. Diagnosis: Pleuropneumonia, pleural abscess. Trueperella pyogenes and Clostridium perfringens were cultured. Video clip 4.11 Holstein bull calf with respiratory distress. The animal was intolerant of almost any movement without becoming severely distressed and would stand as shown with an extended neck, grunting with each respiratory cycle. Radiographs (see Fig. 4.55 in text) demonstrated severe interstitial pneumonia with bullae formation. Diagnosis: Severe interstitial pneumonia; bovine respiratory syncytial virus infection.

Legends for Video Clips

Video clip 4.12

A 5-week-old calf with chronic cough.

Ultrasound findings: Toward the end of the clip, note the dis-

ruption in normal reverberation artifact at the pleural surface. Diagnosis: Mild lobular consolidation of the lung; pneumonia. Video clip 4.13

An 8-week-old healthy calf.

Ultrasonographic appearance of normal bovine lung:

Note parallel reverberation artifacts created at the pleural surface and hyperechoic appearance to the lung surface. Diagnosis: Normal pleural ultrasound. Video clip 4.14 An adult Holstein cow with weight loss, decreased milk production, fever, and subjective increase in size of the mammary veins. Ultrasonography of the liver: Ultrasonographic appearance of the liver from a mature Holstein cow with caudal vena caval thrombosis syndrome. Note the enlargement of the intrahepatic vasculature and caudal vena cava. A large hepatic abscess is also visible toward the left side of the image at several points in the video clip.  Diagnosis: Hepatic abscess, thrombosis, and obstruction of the caudal vena cava. Video clip 4.15 A 4-year-old Jersey cow with acute onset of increased respiratory effort and cough after an epidural. When performing the epidural, air could be heard flowing into the needle, and students were asked to listen to the sound indicating correct placement of the needle. We have noted these respiratory signs in other cows after epidurals when a prolonged “sucking air” sound was reported. We believe air goes from the epidural space into the mediastinum, causing the acute onset of these signs. Affected cattle can also appear distressed and have elevated heart rates, but so far all have recovered with no treatment within 45 minutes. Diagnosis: Suspected pneumomediastinum. Video clip 5.1 An adult Holstein cow presented for acute and progressive onset of ruminal bloat with progressive respiratory distress. The history of rapid progression of ruminal bloat leading to respiratory distress and inability to relieve the bloat by passing a Kingman tube led to the diagnosis of frothy bloat. An emergency rumenotomy was performed and the rumen emptied. The cow made a quick and uneventful recovery. The cause of the frothy bloat could not be determined in this case. Diagnosis: Frothy bloat. Video clip 5.2 An adult Holstein cow with acute anorexia, fever, and a dramatic decrease in milk production. Ultrasonographic examination of the abdomen: Sonogram of cranial ventral abdomen of an adult cow with hardware. The reticulum with can be seen to the bottom right of the image with fluid between it and the diaphragm and fibrin coating its serosal surface. There is also a small amount of free fluid within the thoracic cavity, and the lung can be seen moving in and out of the image. Diagnosis: Peritonitis—hardware. Video clip 5.3 A 4-year-old Holstein with weight loss, decreased appetite, and abdominal distension. Ultrasonographic examination of the abdomen: Sonogram video (first segment) of the cranioventral abdomen of a 4-yearold female Holstein cow with lymphosarcoma. A convex 5- to 2-MHz scan head is used; cranial is to the left side of the image. Viscera are viewed in the following order: first abomasum, then rumen, reticulum,

809

liver, and again reticulum. The lymphosarcoma is the peritoneal mass, 6.5 × 8 cm, hypoechoic, irregularly interdigitating with abnormally hyperechoic fat and blending with the wall of the reticulum and, to a lesser extent, the wall of the abomasum. The sonographic appearance of lymphosarcoma may resemble abomasitis, reticulitis, and peritonitis. In this case, the diagnosis of lymphosarcoma was confirmed by fine-needle aspirate cytology.  Static sonogram demonstrates first the lymphosarcoma and then the right side of the liver made with a vector 4- to 1-MHz scan head. Ventral is to the left side of the image. In the liver is a 4 × 7 cm hypoechoic mass, most likely lymphosarcoma.  Sonogram video (second segment) of normal left craniodorsal abdomen of a 4-year-old female Holstein. A vector 4- to 1-MHz scan head is placed dorsally in a caudal intercostal space and travels ventrally. Ventral is to the left side of the image. Seen first is a very hyperechoic interface oriented parallel to the body wall and casting reverberation artifact—the normal air-filled lung. Ventral to this is a triangular hyperechoic homogenous soft tissue structure, height about 13 cm, containing a vein in cross-section; the normal spleen. Ventral to the spleen is a curved, very hyperechoic structure casting a hypoechoic shadow—the lumen contents of the normal rumen. Note that the wall of the rumen is thin (≈1–2 mm) and difficult to detect. This sequence repeats twice.  Sonogram video (third segment) of normal small intestines of a 4-year-old female Holstein. A vector 4- to 1-MHz scan head is placed caudal to the costal arch on the right side. Ventral is to the left side of the image. The small intestines are the circular structures with normal motility. The intestine diameter is normal (2.2–4.0 cm), the intestinal walls are normal (thin), and the lumen contains normal granular hyperechoic ingesta.  Diagnosis: Lymphosarcoma (first segment and static image). Normal adult bovine abdomen (second and third segments). Video clip 5.4 A 6-year-old Holstein cow with fever, inappetence, decreased production, decreased rumination, and a hunched posture since freshening 1 month earlier. Ultrasound examination of the right abdomen: A vector 4- to 1- MHz scan head is used. The sonogram begins dorsally in the 11th intercostal space and travels ventrally. Ventral is to the left side of the image. At the beginning of the study (first segment), the airfilled right caudal lung lobe, anechoic pleural fluid (abnormal), and normal liver are shown. At times, in the lower left region of the image the aorta and caudal vena cava are seen (1.5 cm in diameter).  The scan head travels farther ventrally (second segment) and is centered on the right kidney. In the center of the kidney are a few 1- to 2-cm, intensely hyperechoic foci that cast faint acoustic shadows. These are calculi. Otherwise, the kidney is normal with normal size (height and width are about 9 cm), lobulated contour, hypoechoic medulla clearly distinguished from the cortex, and the cortex about 1 cm thick.  The normal right adrenal gland (4.5 × 1.5 cm) is visible between the right kidney and caudal vena cava and aorta (third segment). The rumen is the deepest viscus in the image (16 cm deep). Ventral to right kidney is more liver (fourth segment). Ventrally between the liver and rumen are the portal vein, pancreas (3 cm thick), and lymph nodes (2 cm thick). The lymph nodes might be slightly large. When the probe is tipped cranially, the portal vein is larger (2.5 cm diameter). In many adult bovines, the right adrenal gland, pancreas, and periportal lymph nodes are not visible. In this case, conditions were favorable for detecting smaller deeper viscera because the cow was thin, the bowel was relatively empty because of anorexia, and the cow was not pregnant.  Sonogram video (fifth segment) of the right cranioventral abdomen showing focal peritonitis. A convex 5- to 3-MHz scan head is

810

Legends for Video Clips

used. Medial is to the left side of the image. The abomasum is between the body wall and rumen. It is small (6 cm in height) because the lumen is nearly empty. Its wall is normal with layer echogenicity, rugal folds, and it is about 0.5 cm thick between folds. In the peritoneal cavity lateral to the abomasum is focal peritonitis; a large (12-cm) irregularly margined region of compartmentalized peritoneal fluid.  Sonogram video (sixth segment) of the left cranioventral abdomen showing a peritoneal abscess. A convex 5- to 3-MHz scan head is used. Cranial is to the left side of the image. The sonogram starts at a 12-cm abscess with hypoechoic fluid surrounded by a distinct capsule and a dorsal gas cap. Next, the scan head travels cranially to the normal reticulum (note the characteristic convex shape of the reticulum), returns to the abscess, and then travels caudally to abnormal hyperechoic fat near the abomasum and then more caudally to show the rumen and peritoneal (or omental) fluid and fibrin.  Diagnosis: Focal peritonitis from a perforated abomasal ulcer. Video clip 5.5 A 3-year-old Holstein with acute onset of anorexia and decreased production. Ultrasonographic examination of the abdomen: The convex 5- to 3-MHz scan head is oriented in the transverse plane at the midabdomen. The video begins at ventral midline and progresses dorsally through the right side of the midabdomen.  The distended (8-cm) omental bursa is seen as a distinct fluid compartment located between the body wall and the peritoneal cavity. Deep to the omental bursa, the peritoneal cavity is seen to contain a triangle of anechoic fluid between the rumen ventrally and the small intestine dorsally. The fluid within the omental bursa contains irregular webs of fibrin, in this case indicating inflammation.  Diagnosis: Peritonitis (omental bursitis). Video clip 6.1 A 10-week-old Holstein heifer with chronic ill thrift, diarrhea and respiratory disease. Transabdominal ultrasound findings: Using a mid to high frequency probe (suitable for reproductive or thoracic ultrasound examination on-farm), an enlarged abdominal lymph node is visible as an oval-shaped homogeneous structure in the near field (≈2 cm in diameter and 5 cm in length, proximal to a loop of motile intestine). Postmortem examination demonstrated profound mesenteric lymphadenopathy (see Fig. 6.11), and diagnostics confirmed infection with Salmonella Dublin. Diagnosis: Salmonella Dublin- associated chronic mesenteric lymphadenopathy. Video clip 6.2 A 4-year-old Holstein, fresh 5 weeks, with intermittently poor appetite and decreased production for 10 days. Hepatic ultrasound findings: Sonogram video (first segment) and static image of the liver demonstrating five choleliths in a hepatic duct. The convex 5- to 2-MHz scan head is located within a right intercostal space. Ventral is to the left side of the image. The choleliths are the five, less than 1-cm, well-margined, oval, very hyperechoic structures that cast acoustic shadows. These are located in a hepatic duct as evidenced by their linear distribution and location immediately adjacent and parallel to a portal vein. Normal rumen is deep to the liver.  Sonogram video of the liver within a right intercostal space using a vector 4- to 1- MHz scan head demonstrating that deeper portions of the liver contain multifocal choleliths (second segment). These are in hepatic ducts, which are the many hyperechoic branching linear structures parallel to portal veins.  Additionally, the liver has abnormal increased attenuation of sound, resulting in poor penetration and therefore poor visualization

of the deepest portions of the liver. This is a typical but not exclusive finding for lipidosis.  Diagnosis: Hepatic lipidosis, cholelithiasis. Video clip 6.3 A 6-year-old Holstein with anorexia, lethargy, decreased production, and jaundice for 3 days. Hepatic ultrasound findings: Sonogram of the liver and gallbladder; a convex 4- to 2-MHz scan head is used. Dorsal is to the left side of the image (first segment). The liver contains many anechoic, branching, tubular structures, some of which are enlarged hepatic ducts. Normally, hepatic ducts are too small to easily detect. The gallbladder is also enlarged (13-cm diameter) (second segment). Extrahepatic bile duct obstruction was suspected.  Enlarged hepatic ducts (third segment) can be distinguished from enlarged hepatic veins because hepatic ducts are largest (in this case, 4.5 cm) at the porta hepatis, and enlarged hepatic ducts frequently have a tortuous shape. Congested hepatic veins are largest near the caudal vena cava (not demonstrated in this study) and are typically not tortuous. Histologically, liver biopsy showed chronic cholangiohepatitis.  Diagnosis: Cholangiohepatitis. Fusobacterium necrophorum and Streptococcus spp. group D were cultured from the liver biopsy. Video clip 8.1 Ultrasound examination of the normal udder: Longitudinal sonogram of the normal left hind quarter of the udder at the junction of the gland and teat cisterns. These are patent and filled with hypoechoic milk. The gland cistern has a normal full diameter (2.7 cm), and the lactiferous ducts are also full. Video clip 8.2 Ultrasound examination of normal teat: Transverse sonogram of normal left hind teat beginning at the udder and moving distally to the teat sphincter. Distal is to the left side of the image. A linear 12- to 5-MHz probe is used. The teat cistern is patent and filled with hypoechoic milk. Note the ring of blood vessels around the teat cistern. The teat sphincter appears as a centrally located hyperechoic dot, 1 mm in size. Video clip 8.3 A 2-year-old Holstein heifer, recently fresh, with minimal production from the right rear quarter.

Ultrasound examination of teat and gland cistern:

Transverse sonogram of right hind teat beginning at the udder and moving to the teat sphincter (distal is to the left of the image). A linear 12- to 5-MHz probe is used. The proximal portion of the teat cistern is obstructed by many soft tissue webs. Distally, the teat cistern is patent, having a normal diameter lumen (8 mm) and containing hypoechoic fluid (milk). At the tip of the teat, the sphincter is normal, appearing as a centrally located hyperechoic dot, 1 mm in size. Diagnosis: Proximal teat cistern obstruction. Video clip 8.4 A 2-year-old Holstein heifer in which it was difficult to milk out the right rear quarter.

Ultrasound examination of the teat and gland cisterns: Longitudinal sonogram of the obstructed right hind teat be-

ginning at the teat sphincter and moving toward the udder. Distal is to the left of the image. A linear 12- to 5-MHz probe is used. The length of the teat is 3.6 cm. The teat sphincter is normal and appears as a 9-mm length × 1.5-mm thick hyperechoic stripe at the tip of the teat. The distal third of the teat cistern has a normal 9-mm-wide lumen filled with hypoechoic fluid (milk). The proximal two thirds of the teat cistern is obstructed by many soft tissue webs. These extend into the gland cistern.  Diagnosis: Webbed teat obstruction.

Legends for Video Clips

Video clip 8.5 A 2-year-old Holstein heifer, recently fresh, but in which milk cannot be obtained from one quarter. Ultrasound examination findings: Longitudinal sonogram of the abnormal right rear quarter at the gland cistern. Distal is to the left of the image. A convex 8- to 5-MHz probe is used. The teat and gland cisterns are obstructed because the lumen contains many soft tissue webs. The gland cistern is also small in diameter (1.9 cm). The udder parenchyma is normal (hyperechoic background tissue), and lactiferous ducts are normal hypoechoic branching structures full of milk (1-cm lumen diameter).  Diagnosis: Teat and gland cistern obstruction. Video clip 11.1 A 2½-month-old Holstein calf with poor growth and dribbling urine since birth. Ultrasound examination of the right kidney: Transverse image of right kidney made with a convex 5- to 3-MHz scan head. The kidney is large (10 cm diameter) because all of the calyces and the pelvis are enlarged (2–4 cm). These contain anechoic fluid and round hypoechoic material that could be caseated pus, necrotic debris, or blood clots. The renal cortex is very thin (<5 mm). Right nephrectomy was performed. Diagnosis: Pyelonephritis; suspect ectopic right ureter. Video clip 11.2 A 5-year-old Holstein cow with decreased appetite and milk production and appearance of white crystals in the urine. Ultrasound findings: Sonogram of the right kidney. A vector 4- to 1- MHz scan head is used. The center of the kidney contains many oval discrete hyperechoic structures that cast a strong (dark) acoustic shadow (first segment). These calculi have variable diameters with some as large as 2.7 cm. Also in the center of the kidney are five to ten 2-cm anechoic fluid cavities. There are enlarged calyces and an enlarged renal pelvis. The calculi are located dependently within these. Kidney shape (lobulated contour) and corticomedullary definition are normal. Kidney size is normal (11 × 17 cm). The calyces and pelvis are enlarged probably because of obstruction of the right ureter by calculi. The right ureter cannot be seen in the sonograms because it is obscured by acoustic shadowing by renal calculi.  At necropsy, the right renal parenchyma was atrophied, and the right ureter and pelvis were enlarged (8 cm wide) and contained hundreds of calculi (0.1–2 cm). The wall of the pelvis was thick and fibrotic.  Sonogram (second segment) of the left kidney of the same 5-yearold female Holstein with renal failure and calculi. A 4- to 1- MHz vector scan head is used. The left kidney is difficult to visualize, partly because it is so large (≈20 × 30 cm) that its margin extends beyond the equipment’s maximum field of view (26.3 cm deep). The left kidney is also difficult to visualize because portions of the renal capsule are poorly defined and portions of the kidney have poor corticomedullary definition. Several 2-cm renal calculi and multiple fluid cavities, some as large as 2 cm in diameter, are detected. Some of these are centrally located and represent enlarged calyces or the renal pelvis. Other fluid cavities are peripheral, and it is uncertain whether these are parenchymal or capsular. These may represent necrosis, abscesses, or hematomas.  At necropsy, the left renal capsule contained a large hematoma. The renal parenchyma had two infarcts (4 and 9 cm). The kidney was enlarged. The pelvis and ureter contained hundreds of calculi (0.1–2 cm).  Diagnosis: Chronic pyelonephritis—renal calculi. Video clip 11.3 A 4-month-old Holstein heifer calf with a 2-week history of frequent and painful urination and an enlarged umbilicus. Urinalysis performed on a voided urine sample found a large number of white blood cells with intracellular bacteria and some red blood cells.

811

In the video clip the calf can be seen demonstrating agitation, tail switching, flank watching and repeated kicking at the abdomen, consistent with stranguria/dysuria. Ultrasound examination (not shown) revealed an enlarged (3 cm) right umbilical artery with gas echoes seen in the thickened artery. Urine culture had 105 CFU Trueperella pyogenes and 104 CFU Escherichia coli. Surgery was performed, and both the infected umbilical artery and the associated diseased part of the bladder were removed. The clinical signs were improved the following day, and by day 3 after surgery, the calf was urinating normally. She was also treated with ampicillin for 7 days.  Diagnosis: Bacterial cystitis associated with umbilical remnant infection. Video clip 11.4 A 2-year-old Holstein cow with a 1-week history of hematuria and progressive inappetence. The urinalysis revealed degenerative neutrophils and large numbers of bacteria. Endoscopy findings: Endoscopy revealed an edematous and inflamed-appearing bladder with exudate and blood clots on the floor of the bladder. There is also an ulcerative lesion on the ventral bladder mucosa. A biopsy of this confirmed necrotic cystitis. The cow was treated with penicillin and improved, but long-term follow-up was not available.  Diagnosis: Necrotic cystitis caused by Corynebacterium renale. Video clip 11.5 An 11-year-old Holstein cow with a 6-month history of hematuria and stranguria. The cow was in good body condition, and all other examination findings were normal. Endoscopy findings: Endoscopy reveals a large proliferative mass on the ventral floor of the bladder. In the middle of the video, the apex of the bladder can be seen when the scope is retroflexed (causing the image to be upside down). The ureters can be seen traversing through the dorsal bladder wall and opening, with urine flow at the trigone.  Diagnosis: A biopsy confirmed a transitional cell carcinoma. Video clip 11.6 A 2½-month-old Holstein with poor growth and an umbilical mass. Umbilical ultrasound findings: The umbilical mass is displayed in longitudinal plane (first segment) where cranial is to the left side of the image and transverse (second segment) planes. The sector 5- to 3-MHz scan head is placed on the ventral aspect of the umbilical mass. The umbilical mass has findings typical of an abscess. It is a large (15 cm) single compartment containing echoic fluid and surrounded by a distinct capsule. In real time, it has no motility. The abscess extends caudally in the peritoneal cavity and has a tubular shape, indicating involvement of the urachus or an umbilical artery. The peritoneal cavity is deep in the image, beginning at the calipers.  Sonogram video (third segment) of the umbilical abscess and the normal peritoneal cavity cranial to the abscess demonstrating that the abscess does not involve the abomasum. The convex 8- to 5-MHz scan head is oriented in the transverse plane and begins on the ventral aspect of the umbilical mass and proceeds cranially. The umbilical mass is an abscess with a thick capsule containing echoic fluid. When the scan head reaches the peritoneal cavity, the abscess is no longer detected, and the image changes to show normal abomasum, which has a thin wall (1.2 mm) with layers, thin rugal folds, and normal ingesta that is of much greater echogenicity than the abscess fluid.  Sonogram video (fourth segment) of urachus or umbilical artery abscess demonstrating that the abscess contains gas. The convex 8to 5-MHz scan head is oriented in the transverse plane in the caudoventral abdomen. The video begins at the apex of the urinary bladder, which contains anechoic urine and has a mildly thick wall (9 mm).

812

Legends for Video Clips

The video proceeds caudally to show an 8-cm-diameter abscess in the peritoneal cavity immediately cranial to the urinary bladder. In addition to the distinct thick capsule and echoic fluid, the abscess has a dorsal gas cap forming a straight, smooth, very echoic, linear interface that casts acoustic shadows at the deep edge of the fluid.  Sonogram of the urachus or umbilical artery abscess and urinary bladder in the longitudinal plane (cranial is to the left side of the image) using a convex 8- to 5-MHz scan head (static image, fifth segment). The capsule of the abscess is continuous with, and distorts, the cranial aspect of the urinary bladder.  Diagnosis: Urachal and umbilical artery abscess. Video clip 12.1 Adult Holstein cow acutely lame and nonweight bearing on right hind leg. Caudoventral dislocation of the right coxofemoral joint (into obturator foramen) being reduced under general anesthesia in a mature Holstein cow. This clip shows, by use of mechanical devices, including a calf jack, the profound difficulty faced in lengthening and abducting the femur to bring the femoral head lateral to the pelvis and back cranially toward the acetabulum. This is often impossible in a conscious or even merely sedated individual because of the pain and resistance to such marked tension on the injured limb.  Diagnosis: Coxofemoral luxation. Video clip 12.2 Adult Holstein cow acutely lame and nonweight bearing on right hind leg. Continued manipulation of the right hind limb of the cow shown in Video clip 12.1. After limb lengthening and radiographic confirmation that the femoral head had been brought close to the acetabulum, persistent multiple-person pressure is being applied over the region of the greater trochanter and proximal femur while limb lengthening attempts are still ongoing in an attempt to relocate the femoral head into the acetabulum.  Diagnosis: Coxofemoral luxation, attempted manual repair. Video clip 12.3 Adult Holstein cow acutely lame and nonweight bearing on right hind leg. Persistence with the cow from Video clips 12.1 and 12.2 was associated with successful relocation of the femoral head into the acetabulum; at about the 45 second mark, it is clear that continued efforts with pressure over the greater trochanter have been successful at reducing the dislocation.  Diagnosis: Coxofemoral luxation, successful repair. Bovine Neurology Videos: Signalment and history (H) are given first followed by AD = Anatomic diagnosis (neuroanatomical location of dysfunction) CD = Clinical (or pathologic) diagnosis Video clip 13.1 A 3-week-old Holstein calf. H: Abnormal gait since birth with no change in the signs. AD: Cerebellum. CD: Necropsy diagnosis of cerebellar hypoplasia and atrophy. Presumptive in utero bovine viral diarrhea virus infection. Video clip 13.2 Three Holstein calves born to different dams on one farm in a 10-day period. H: All unable to stand since birth. AD: Cerebellum. CD: Necropsy diagnosis of cerebellar hypoplasia and atrophy. Presumptive in utero bovine viral diarrhea virus infection.

Video clip 13.3 Two Holstein calves, 1 and 2 weeks old, respectively. H: Both unable to stand since birth. AD: Cerebellum. CD: The first calf had no lesions at necropsy and is an example of a presumptive congenital functional cerebellar disorder. The second calf had lesions of a presumptive in utero bovine viral diarrhea virus infection. There are no obvious clinical differences. Video clip 13.4 A 4-day-old Holstein calf. H: Born unable to get up with diffuse tremors associated with any muscle activity. When recumbent and totally relaxed, the tremors disappear. AD: Diffuse central nervous system. CD: Necropsy diagnosis of hypomyelinogenesis. Presumptive in utero bovine viral diarrhea virus infection. Video clip 13.5 A 5-day-old Holstein calf. H: Since birth, action-related tremors have been present primarily in the pelvic limb and trunk muscles. When recumbent and totally relaxed, the tremors disappear. AD: Diffuse central nervous system (CNS). Whole-body tremors require a diffuse disturbance of CNS neurons or their myelin. CD: Necropsy diagnosis of diffuse axonopathy most pronounced in the spinal cord. Presumptive inherited disorder. Video clip 13.6 Two, 2-day-old Polled Hereford calves. H: Unable to stand since birth. Diffuse tremors are associated with any muscle activity. When recumbent and totally relaxed, the tremors disappear. AD: Diffuse central nervous system (CNS). CD: Necropsy diagnosis of diffuse CNS edema (“cerebral edema”), a form of spongiform degeneration, which is an inherited autosomal recessive metabolic disorder of Polled Herefords. Video clip 13.7 A 10-day-old Brown Swiss calf. H: The calf developed fever and depression on day 3 of life. The calf ’s plasma protein concentration was 5.2 g/dL, so failure of passive transfer of antibodies was suspected as a predisposing cause for sepsis. The calf was treated with ceftiofur, intravenously administered crystalloids and plasma in additional to nutritional support, and appeared to be responding well until day 10. On day 10 of life, the calf had an acute onset of tremors, and ataxia and fever recurred. Cerebrospinal fluid (CSF) collected from the lumbosacral site was grossly discolored and suppurative. The calf was euthanized, and the brain is shown in Fig. 13.9. Escherichia coli was cultured from both the CSF and from a blood culture that had been collected on hospital admission. This organism demonstrated in vitro resistance to ceftiofur and all other antibiotics on the panel except for amikacin. AD: Prosencephalon, caudal brainstem, cerebellum. CD: Suppurative meningitis. Video clip 13.8 A 4-week-old Angus calf. H: Two weeks of progressive depression and ataxia. Recumbent for 3 days. AD: Cerebellum, pons, and midbrain; opisthotonus can occur with disorders of these anatomic sites. CD: Cerebrospinal fluid contained elevated levels of protein and degenerate neutrophils. Necropsy diagnosis of suppurative meningitis.

Legends for Video Clips

Video clip 13.9 A 6-month-old Holstein calf. H: One week of depression, excessive recumbency, sialosis, and tongue protrusion. AD: Cranial nerves II through XII, caudal brain stem for the mild ataxia or paresis (upper motor neuron/general proprioception systems); more likely parenchymal lesion. CD: Necropsy diagnosis of probable pituitary abscess that ruptured and extended caudally along the ventral surface of the brain stem. Video clip 13.10 An 18-month-old Holstein calf. H: Depression progressing over 48 hours to obtundation and reluctance to move. AD: Diencephalon based on the severe obtundation from interference with the ascending reticular activating system in an animal that is still able to walk. CD: Necropsy diagnosis of a large focal pituitary abscess. Video clip 13.11 A 3-year-old Holstein cow. H: Six days of intermittent circling to the right and inability to eat normally. AD: Cranial nerves III through XII—left pons and medulla. This cow had vision but could not close the eyelids because of bilateral facial paralysis. The extensive cranial nerve dysfunction with the mild gait disorder suggested an extramedullary lesion, which turned out to be incorrect in this cow. CD: Lumbosacral cerebrospinal fluid contained 26 white blood cells/μL with 60% macrophages. Necropsy diagnosis of listeriosis with extensive involvement of cranial nerve nuclei. Video clip 13.12 A 2-year-old Hereford cow. H: Ten days of progressive depression and dysphagia. AD: Pons and medulla. CD: Necropsy diagnosis of listeriosis. Video clip 13.13 An 18-month-old Holstein heifer. H: Acute onset of propulsive circling to the left when stimulated. Intravenous potassium penicillin and supportive therapy led to a full recovery. The heifer was pregnant at the time and maintained the pregnancy to term. This heifer also demonstrated persistent medial strabismus (see Fig. 13.16). AD: Extrapyramidal system (there was no evidence of vestibular dysfunction) and brainstem (trochlear nerve). CD: Suspected listeriosis. Video clip 13.14 A 5-year-old Holstein cow. H: Five days of progressive difficulty using the pelvic limbs associated with overflexed tarsi and buckled fetlocks. She was recumbent at hospitalization and unable to urinate, and on rectal examination, she had a large bladder. Loss of tail movement and anal reflex developed within the first 6 hours after hospital admission. She became quite agitated and acted in discomfort. AD: Lumbosacrocaudal spinal cord segments or spinal nerves. Unusual “stringhalt-like” flexor reflex action in the paretic pelvic limbs, which probably reflected disturbed inhibition in the lumbosacral grey matter. Lumbosacral cerebrospinal fluid contained 9 white blood cells/μL (lymphocytes and macrophages) and 97 mg protein/dL. CD: Necropsy diagnosis of rabies viral myelitis.

813

Video clip 13.15 A 6-month-old Holstein calf. H: Acute onset of lethargy, loss of vision, and ataxia. Progressed to recumbency in 24 hours. Improved after therapy. AD: Prosencephalon. Note depression and loss of vision but the ability to walk. The pupils were small and still reactive to light. The initial signs reflected a diffuse brain lesion that had recovered to just the prosencephalic signs seen on the video. CD: Presumptive thiamine-deficient polioencephalomalacia. Video clip 13.16 A 6-month-old Holstein calf. H: Acute onset of lethargy, loss of vision, and shuffling gait. Became recumbent in 24 hours. AD: Prosencephalon. CD: Necropsy diagnosis of polioencephalomalacia. Presumptive thiamine deficiency but beware of sulfur and lead toxicity that cause the same lesions. Video clip 13.17A A 2-month-old Holstein calf. H: One week of a “swaying” gait and progressive depression with loss of vision. AD: Cerebrocortical disorder. CD: Blood ammonia was greater than 600 μmol/L (normal, <40 μmol/L). At necropsy, a portocaval shunt was found and a diffuse encephalomyelopathy. On rare occasions, spinal cord signs without obvious cerebral deficits have been observed in other calves with portosystemic shunts (see Fig. 13.31 and Video clip 13.17B). Video clip 13.17B A 2-month-old Holstein calf. H: One week of abnormal gait. AD: C1 to C5 spinal cord segments, focal or diffuse. CD: Either discospondylitis or an abscess was suspected. Radiographs were normal. At necropsy, a portocaval shunt was found with a diffuse hepatic form of encephalomyelopathy. No cerebral signs were reported or observed. Similar spinal cord signs have been observed in other calves with portosystemic shunts. Video clip 13.18A An 18-month-old Holstein heifer. H: Escaped from barn 2 days earlier; now demonstrating blindness, hyperesthesia, and ataxia. AD: Prosencephalon (limbic system) and diffuse brain. CD: Elevated blood lead concentrations (from licking an old battery). Clinical signs are consistent with lead poisoning. Video clip 13.18B A yearling Brown Swiss heifer. H: This heifer had 2 days of depression and anorexia. On hospital examination, it was noted that the heifer had both a decreased menace and vision but normal pupillary light responses. One day later, the heifer was noted to be grinding her teeth, as can be heard in the video, and abnormally high blood lead levels were found. The heifer was treated with calcium disodium ethylenediaminetetraacetic acid and thiamine intravenously and administered magnesium sulfate orally. She began to improve after 3 days of treatments and had a complete clinical recovery. The owners were instructed by oral communication and letter that follow-up testing for milk lead levels would be required if she were to enter the milking herd. The source of the lead poisoning in this case was unknown. AD: Cerebral cortex bilateral. CD: Lead poisoning.

814

Legends for Video Clips

Video clip 13.19 A 10-day-old Brown Swiss heifer. H: The heifer developed acute and persistent facial twitching with chewing “bubble gum” type seizures. Serum chemistry testing found a profound hypernatremia (serum sodium, 188 mEq/L). Despite attempts at gradual sodium reduction using hypertonic fluids, the neurologic status deteriorated, and the animal was euthanized. AD: Prosencephalon. CD: Salt poisoning. Video clip 13.20 A 3-year-old Jersey cow. H: Two weeks postpartum, acute depression, decreased milk production, and abnormal behavior. Video shows the maniacal chewing, neck extension, and closed palpebral fissures all observed on hospital admission. AD: Prosencephalon (limbic system). CD: Strong elevation of urine ketones, decreased bicarbonate, and increased anion gap diagnosed as ketoacidosis. The clinical signs of nervous ketosis resolved with dextrose therapy. Video clip 13.21 A 2-year-old Holstein heifer, fresh for 2 weeks. H: This heifer had an acute onset of circling to the right and propulsively and frequently sticking her tongue out in a dramatic fashion. The cow was strongly ketotic based on urine testing and was sedated (20 mg xylazine) and treated for nervous ketosis with intravenous dextrose and orally administered propylene glycol in addition to transfaunation and forced feeding. The heifer was improved the following day and appeared normal 2 days after treatment was begun. AD: Prosencephalon—limbic system. CD: Nervous ketosis. Video clip 13.22 A 2-week-old Holstein calf. H: Since birth, unable to stand and walk with the pelvic limbs. AD: T3 to L3 spinal cord segments, focal or diffuse. The simultaneous use of the pelvic limbs, referred to as “bunny hopping,” is a very reliable sign for some form of myelodysplasia. This simultaneous activity is also observed on testing the flexor reflex. Spinal cord malformations are often accompanied by vertebral column malformations. The latter was palpated at L2 and L3 in this calf. CD: Radiographs and computed tomography (CT) images diagnosed an L2 to L3 malformation. The CT demonstrated segmental spinal cord hypoplasia at this level. Necropsy diagnosis of thoracolumbar myelodysplasia with segmental hypoplasia of the L2 and L3 segments and sacral segment diplomyelia. Video clip 13.23 A 2-day-old Simmental cross calf. H: Recumbent since birth. AD: T10 to T11 focal transverse lesion. This was based on the paraplegia and the T13 line of analgesia. The simultaneous pelvic limb movements were all uninhibited reflex actions similar to spinal walking. There were no vertebrae palpated from T13 to L2. CD: Myelodysplasia and vertebral malformation were confirmed at necropsy. There were no vertebral arches between T13 and L2, and there were no spinal cord segments from T13 through L3. There was myelodysplasia in the caudal thoracic segments and from L4 through the caudal segments. The extreme pelvic limb hyperreflexia seen here was caused by the complete absence of any brainstem inhibition of the lumbosacral grey matter.

Video clip 13.24 A 1-week-old Holstein calf. H: Abnormal use of the pelvic limbs since birth. AD: T3 to L3 spinal cord segments, focal or diffuse. The scoliosis indicates a vertebral malformation, and the congenital simultaneous pelvic limb action indicates a myelodysplasia. CD: Necropsy diagnosis of multiple thoracolumbar spinal cord segment myelodysplasia. Video clip 13.25 A 1-month-old Holstein calf. H: Rapid progression of inability to stand and walk with the pelvic limbs. AD: T3 to L3 spinal cord segments-focal or diffuse. This is based on the spastic paresis (upper motor neuron dysfunction) and pelvic limb ataxia (general proprioception dysfunction) with retained spinal reflexes and nociception. CD: Radiographic diagnosis of discospondylitis at the T13 to L1 articulation with a compression fracture of T13. Video clip 13.26 A 7-year-old Holstein cow with progressive weakness and an abnormal gait. AD: Tetra-ataxia and paresis, which could be caused by a C1 to C5 lesion or diffuse or multifocal spinal cord disease. CD: Spinal lymphosarcoma located epidurally in the caudal thoracic and cranial lumbar spine. Although the predominant neoplastic lesion was noted grossly in a more caudal location, there was histologic evidence of infiltration around the cervical cord, explaining the clinical evidence of tetraparesis. Video clip 13.27 A 1-year-old Holstein heifer. H: Found at pasture with an abnormal gait. AD: Cranial thoracic spinal cord segments. Spastic paraparesis and pelvic limb ataxia with lower motor neuron signs of short strides in the thoracic limbs suggest a C5 to T2 spinal cord segment anatomic diagnosis, but note the strength shown by this heifer in her thoracic limbs when she stumbles and is able to get back up. This suggests that the upper motor neuron/general proprioception lesion is in the cranial thoracic spinal cord segments, and there is loss of thoracolumbar axial muscle function. CD: Necropsy diagnosis of a fracture of T4 with displacement into the vertebral foramen. The cause of the fracture was unknown. There were no lesions of any vertebral body infection. Video clip 13.28 A 2-year-old Holstein heifer with a dorsal arch in her back since birth. AD: Note kyphosis in the region of the malformation and hind limb paresis and ataxia consistent with a thoracic cord compression. CD: Congenital vertebral malformation at T9 to T10 (see Fig. 13.48). Video clip 13.29 An 8-month-old Holstein bull with chronic stumbling in the rear legs. AD: T2 to L4 spinal cord disease. Note the bilateral hind limb ataxia and paresis. CD: Congenital vertebral malformation between T1 and T4 (see Fig. 13.49). Video clip 13.30 A 5-month-old Holstein calf. H: One month of a progressively abnormal gait in the left pelvic limb. AD: Sciatic-tibial nerve or S1, S2 spinal cord segment, gamma efferent dysfunction.

Legends for Video Clips

CD: These signs of extreme hyperextension of the tarsus when attempts are made to protract the limb are typical of the functional disorder referred to as spastic paresis or “Elso heel.” There are no microscopic lesions. The hyperactive gastrocnemius muscle activity is caused by uninhibited gamma efferents in the sacral spinal cord segments. This is an inherited disorder in many breeds of cattle. Video clip 13.31 A 3-month-old Hereford calf. H: Abnormal use of the right pelvic limb since birth with no change in the clinical signs. AD: Right femoral nerve, L4 to L5 spinal cord segments, or spinal nerve roots. Note the inability to support weight when the left pelvic limb is advanced. CD: Presumptive dystocia with overextension of the hip during calving and injury to the femoral nerve as it emerges from the iliopsoas muscle or avulsion of its nerve roots. At necropsy, the latter was found in this calf. Video clip 13.32 A 3-day-old Holstein calf. H: Abnormal use of the pelvic limbs since birth. AD: Bilateral femoral nerve, L4 to L5 spinal cord segments, or spinal nerve roots. The lack of pelvic limb support is most severe in the left pelvic limb. Note the intact nociception on the medial side of the left crus, which is innervated by the saphenous nerve, a branch of the femoral nerve. This suggests a better prognosis. CD: Presumed femoral nerve injury secondary to a dystocia. This calf recovered in a few weeks. Video clip 13.33 A 4-year-old Holstein. H: Two months of progressive gait abnormality in both pelvic limbs that began in the right pelvic limb. AD: Bilateral tibial nerve, S1 and S2 spinal cord segments, or spinal nerves. The latter is least likely with the normal tail, anus, and perineum. Note the overflexion of the tarsus typical of a tibial nerve dysfunction. The buckling dorsally of the fetlock is a unique sign of tibial nerve dysfunction seen only in cattle. CD: On rectal examination, a bony defect was palpated on the ventral surface of the sacrum. At necropsy, there was a healed displaced fracture of S2 with fibrosis of the intervertebral foramina entrapping the S1 and S2 spinal nerves. The fracture was presumed to be caused by the cow having been ridden by another cow or bull. Video clip 13.34 A 2-year-old Holstein. H: Rapidly progressive abnormal gait in both pelvic limbs. AD: Bilateral L6, sacral, and caudal nerves or spinal cord segments. Compared with the case in Video clip 13.33, note the loss of tail tone and severe hypalgesia of the sacrocaudal dermatomes in this animal. CD: Necropsy diagnosis of extensive L6 to S1 discospondylitis, with suppurative inflammation involving multiple lumbosacral spinal nerves. Video clip 13.35 Two Holstein calves, 2- and 4-months-old respectively. H: Ten days of progressive ataxia, head tilt, and ear droop. AD: Two-month-old calf: right cranial nerves VII and VIII. AD: Four-month-old calf: left cranial nerve VII, pons, and medulla. Note the depression, the need for assistance to stand, and the neck extension.

815

CD: Two-month-old calf; radiographic diagnosis of otitis media/ interna. This is a very common cause of facial nerve or vestibulocochlear nerve dysfunction in calves. CD: Four-month-old calf; necropsy diagnosis of suppurative otitis media/interna, with meningitis and abscess formation in the left side of the pons and medulla. Video clip 13.36 A 1-month-old Holstein calf. H: Bilateral ear droop developed over a few days. AD: Bilateral facial nerve. CD: Bilateral otitis media diagnosed on computed tomography imaging. Video clip 13.37 A 12-year-old Holstein cow. H: Two months before the videotaping, the owner of this cow treated her for “milk fever” with calcium gluconate presumably administered intravenously in the right external jugular vein. A large mass slowly developed at the injection site. The farmer noted that on cold mornings, there was less mist emerging from the cow’s right naris during expiration. AD: Right sympathetic innervation of the head. The right side of the muzzle is dry; the right ear is warmer than the left. There is a smaller right palpebral fissure. Miosis and third eyelid protrusion were minimal. Loss of vasoconstriction in the right nasal cavity would explain the decreased air flow and less mist seen on expiration on a cold morning. CD: Presumptive dysfunction of the right cervical sympathetic trunk due to the granuloma on the right side of the neck caused by the extravascular injection of calcium gluconate; Horner’s syndrome. Video clip 13.38 A 1-week-old Holstein calf. H: Since birth, this calf was inactive, walked with short strides, and preferred to remain recumbent. AD: Diffuse neuromuscular. CD: A positive response to intravenous Tensilon suggested congenital myasthenia gravis. Over the next few weeks, this calf improved to normal. A delay in the development of normal neuromuscular receptors was presumed. Video clip 13.39 A 1-month-old Holstein calf. H: This calf developed a stiff gait and became recumbent over a few days. AD: Diffuse spinal cord ventral grey columns and brainstem nuclei. Note the typical facial expression with the ears held caudally and the tight lips. CD: Tetanus caused by infection with Clostridium tetani. This calf died from respiratory depression 2 days later. Video clip 13.40 A 6-week-old Polled Hereford calf. H: Since birth, this calf had been recumbent and unable to stand and exhibited extensor rigidity. AD: Diffuse spinal cord ventral grey columns. The clinical signs observed are tetany. Note the prolonged extensor muscle activity when stimulated with mild relaxation between stimuli, and not attempting to move. CD: This is a hereditary tetany of Polled Herefords caused by an autosomal recessive gene, which results in the abnormal formation of glycine receptors on motor neuronal cell membranes.

816

Legends for Video Clips

Video clip 14.1 An adult Holstein cow. H: This cow was presented for a displaced abomasum, and the rapid horizontal movement of both eyes was noted. This movement has almost certainly been present since birth but likely went unnoticed. Diagnosis: Pendular nystagmus in a 5-year-old Holstein cow. Video clip 15.1 A 2-year-old first lactation cow with acute onset of tremors most pronounced around the head. (Courtesy of Dr. Matthew Chuff.)

H: A serum sample was submitted for electrolyte measurements; the magnesium level was 0.4 mg/dL, and the total calcium level was less than 4 mg/dL. AD: Neuromuscular disease. CD: Hypomagnesemic tetany.