The galactopoietic actions of bovine somatotropin are both direct and indirect. Indirect actions are apparently mediated by the insulin-like growth factor (IGF) system. The objective of this study was to compare systemic (plasma) versus local (lymph) concentrations of IGF. Afferent mammary lymph most nearly represents the extracellular fluid that is bathing mammary tissue. Catheters were surgically implanted in the jugular vein and the superficial afferent mammary lymph vessels of four lactating cows. A crossover design was utilized to evaluate the effects of bovine somatotropin (bST). After 2 d of basal sampling, either bST (40 mg/d) or excipient was administered daily for 5 d. After the conclusion of the bST study, a second study was conducted in which cows were deprived of feed for 36 h. Blood and lymph were simultaneously sampled at least every 6 h throughout both studies. Milk yield was increased by bST, and concentrations of IGF-I were increased in plasma and lymph. The relationship between plasma and lymph concentrations for IGF-II, bST, insulin, glucose, urea nitrogen, and nonesterified fatty acids were similar during bST treatment. Milk yield was reduced 76% by 36 h of feed deprivation. Feed deprivation also caused a reduction of IGF-I in plasma, but concentrations of IGF-I in lymph were not altered. In contrast, changes in IGF-II, bST, insulin, glucose, urea nitrogen, and nonesterified fatty acids that were caused by feed deprivation followed similar patterns in plasma and lymph. Clearly, if IGF-I mediates the mammary actions of bST, then concentrations of IGF-I in plasma correlate with milk yield responses as well as, if not better than, concentrations in lymph.

Summary Nine adult female sheep were each surgically fitted with an Ivan and Johnston reentrant cannula in the cranial part of the duodenum just distal to the pylorus. By diversion (loss) of abomasal outflow, this model has been shown to consistently induce hypochloremic, hypokalemic metabolic alkalosis, accompanied by hyponatremia and dehydration. Each sheep was subjected to 3 treatment trials, each preceded by a 24-hour prediversion period, and a diversion period during which a syndrome of hypochloremia (68 ± 2 mEq/L), hypokalemia, hyponatremia, and metabolic alkalosis was induced. Development of this syndrome was attributable to losses of large amounts of acid and electrolytes in the abomasal effluent. Mean total electrolyte contents of the effluent were: Cl−, 650 ± 27 mEq; Na+, 388 ± 23 mEq; and K+, 123 ± 12 mEq, with total volume loss ranging from 3.6 to 10.0 L of gastric contents and pH ranging from 3 to 5. Decreases in plasma electrolyte concentrations also can be attributed to decreased intake, because anorexia developed shortly after the onset of diversion. Electrolyte losses in urine during diversion were minimal for Cl− (mean ± sem, 12.0 ± 5.1 mEq), but were greater for Na+ (124.2 ± 14.5 mEq) and K+ (185.1 ± 31.2 mEq). Treatments consisted of 0.9% NaCl (300 mosm/L), 3.6% NaCl (1,200 mosm/L), and 7.2% NaCl (2,400 mosm/L) administered over a 2-hour period, with the administered volume determined by the estimated total extracellular fluid Cl− deficit. Significant difference was not found among treatments, with all solutions resulting in return of clinicopathologic and physical variables to prediversion values within 12 hours of treatment. We concluded that rapid iv replacement of Cl−, with small volumes of hypertonic saline solution, is safe and effective for correction of experimentally induced hypochloremic, hypokalemic, metabolic alkalosis in sheep.

This paper outlines the history and development of research in the area of animal welfare as reflected in the 100 yr that the Journal of Dairy Science has been published. The first paper using the term “animal welfare” was published in 1983; since then (to May 2017), 244 papers that reflect growing interest regarding how farm animals are cared for have been published. Much of the scientific work to date has focused on issues related to cow health, such as lameness, and methodologically many papers use behavioral measures. In addition to this science-based research, the journal has taken on the role of publishing work of social scientists that addresses the role of the human factors relating to animal welfare, including research on citizen, consumer, and farmer attitudes toward welfare issues. We call for further research focused on societal perspectives and for new biological research focused on developing issues, such as cow–calf separation and pasture access.

The effects of bovine somatotropin (bST) administration and abomasal protein infusion on nitrogen metabolism were investigated using four abomasally-cannulated Holstein steers in a 4 × 4 Latin square design. Treatments were factorially arranged to include daily abomasal infusion (water or casein, 0.9 g/kg body wt) and daily bST injection (0 or 200 μg/kg body wt). Each treatment period lasted for 23 d and consisted of an adjustment period (d 1 to 7), casein infusion (d 8 to 23) and bST treatment (d 10 to 23). Nitrogen metabolism and serum insulin-like growth factor-I (IGF-I) profiles were characterized on d 16–22. Animals were fed a total mixed diet balanced to achieve 0.75 kg gain/d and supplemented to provide 115% of requirements for crude protein and minerals. Nitrogen retention was increased by casein and bST individually (21 and 33%, respectively) or in combination (75%). Somatotropin treatment increased the biological value of absorbed N, which was consistent with reductions in plasma urea nitrogen. Circulating IGF-I was increased by bST and was highly correlated (r = 0.73) with N retention. Overall, bST altered requirements so that less absorbed N was required per unit of N retained. However, results also demonstrated that because of limitations in amino acids supplied from microbial and ruminal escape protein in young growing cattle, amino acid supply may limit the magnitude of N retention response to bST under many situations.

The medical records of 66 calves with atresia coli were reviewed; 64 calves were examined at the New York State College of Veterinary Medicine, and 2 calves were examined at the New Bolton Center. In each case, the site of the atresia was within the spiral loop of the ascending colon. In 1 of these calves, a segment of jejunum was also atretic. Absence of feces, progressive weakness, and abdominal distension were the most common clinical signs observed. Other congenital abnormalities were detected in 12 (18%) of 66 calves. Of the 66 calves examined, 5 were euthanatized or died on admission, and 61 had an exploratory celiotomy performed. Eight calves were euthanatized or died during the surgery. In the remaining 53 calves, surgical treatment consisted of enterotomy followed by meconium evacuation, resection of the proximal blind end (in 30 calves), and restoration of intestinal continuity. Restoration of intestinal continuity was done either by side-to-side anastomosis of the proximal to distal blind ends (5 calves), or by side-to-side or end-to-side anastomosis of the proximal blind end to the descending colon (48 calves). Of the 66 calves seen, 27 (41%) were discharged from the hospital, and 11 of these reached reproductive age (11 calves were lost to follow-up before they were 2 years old). From the 11 calves reaching reproductive age, 33 calves were born, one of which may have had atresia coli. The owners should anticipate that long-term survivors likely will have loose feces and normal offspring, but may not grow as well as otherwise expected.

Five adult 40- to 50-kg female sheep were surgically fitted with a reentrant cannulae placed in the proximal part of the duodenum just distal to the pylorus. By diversion of abomasal outflow, this model has been shown to produce hypochloremic metabolic alkalosis accompanied by dehydration, hypokalemia, and hyponatremia. Each sheep was subjected to 3 separate, 12-hour IV treatment trials, in each case preceded by a control period of 48 hours, and a diversion period of 36 to 96 hours, during which a hypochloremic (Cl- less than or equal to 60 +/- 2 mEq/L) metabolic alkalosis with hypokalemia and hyponatremia was produced. Treatment 1, consisting of 6 L of isotonic Na gluconate, was designed to replace volume without replenishing the Cl-1 deficit. Although hydration improved, plasma Cl- decreased further, and the sheep became increasingly weak and depressed. Treatment 2, consisting of 2 L of 1.8% NaCl, was designed to replace the Cl- deficit without replacing total volume. Plasma Na+ and Cl- concentrations returned to normal during the 12 hours of treatment; acid-base balance and plasma K+ concentrations returned to normal within 36 hours of treatment. During treatment 3 (control, no treatment), measured metabolic values changed minimally. We concluded that the IV replacement of Cl- without K+ is effective in the correction of experimentally induced hypochloremic metabolic alkalosis in sheep.

Clinical and surgical findings in 458 dairy cows with right displacement of the abomasum or abomasal volvulus (AV) were analyzed to determine the association between these variables and the outcome (productive, salvaged, or terminal) of the affected cow. Heart rate at initial examination was higher in the salvaged and terminal groups of cows (P less than 0.0001) than in the productive group. The plasma Na+ concentration was lower in the salvaged and terminal groups of cows (P less than 0.0001) than in the productive group. The plasma C1- concentration was lower in the salvaged group of cows than in cows with either productive or terminal outcomes (P less than 0.0001). Anion gap was significantly higher (P less than 0.0001) in the salvaged and terminal groups than in cows classified as productive. On the basis of surgical findings, cattle with right displacement of the abomasum were more likely to survive than cows with AV. Cows that required fluid decompression of the abomasum via abomasotomy were less likely to survive than those in which gaseous decompression was performed. Cows with evidence of vascular compromise of the abomasal wall were less likely to survive than those with normal abomasal serosa. Preoperative heart rate and anion gap had positive correlations with the presence of abomasal necrosis, whereas temperature, venous blood pH, plasma bicarbonate, and base excess concentrations had negative correlations. Cows in terminal stages of AV were likely to have a mixed primary acid-base disturbance, consisting of metabolic alkalosis with superimposed metabolic acidosis. These findings were highly correlated with abomasal necrosis.

Clinical, clinicopathological and surgical data from 458 adult dairy cows with right abomasal displacement or abomasal volvulus were analysed to determine the association between these variables and outcome, classified as productive, salvaged or terminal. Heart rate was higher in the salvaged and terminal cattle, than the productive cattle. Hyponatraemia was increasingly severe in the salvaged and terminal cows. All groups of cows were hypochloraemic and hypokalaemic, with the lowest values in the salvaged group. Cows in the productive and salvaged groups had metabolic alkalosis. As the outcome became less favorable there was evidence of superimposed metabolic acidosis with increased anion gap.

A mucosal lesion was created in the center of each test sinus of 6 mature, healthy, nonlactating Holstein cows by resecting a circumferential band of mucosa. Each lesion was then treated by implantation of strip grafts of autogenous oral mucosa, temporary silastic tube implant, or a combination of strip grafts and temporary silastic tube implant. All teats were evaluated for patency 6 weeks after treatment, and tube implants were removed through a second thelotomy incision. All teats were reevaluated for gross and radiographic patency 12 weeks after treatment, and teats were collected for histologic evaluation of lesions. All 4 teats treated with grafts only were obstructed at 6 and 12 weeks after treatment. Incomplete coverage of the lesion with mucosa was observed in all 4 teats. The major source of obstruction was proliferation of epithelium and keratin into the lumen. All 8 teats treated with temporary silastic tube implants alone were patent at 6 weeks after treatment, but were obstructed at 12 weeks after treatment. Foci of mucosa at the lesion site were detected in only 2 of the 8 teats. Obstruction resulted from proliferation of granulation tissue into the lumen. All 12 teats treated with grafts and a temporary tube implant were patent at 6 weeks after treatment and 11 of 12 were patent at 12 weeks after treatment, although marked luminal narrowing was evident in 9 of 11 teats. Partial to complete coverage of the lesion with mucosa was seen in all teats. Proliferative granulation tissue, epithelium, and keratin contributed to luminal narrowing in 10 of 11 patent teats. Bacteriologic culture of quarters from 6 of the 11 teats patent at the final evaluation yielded pathogens.

SUMMARY Hypochloremic metabolic alkalosis accompanied by hypokalemia and hyponatremia was induced experimentally in 7 adult sheep by diversion (loss) of gastric contents through an Ivan and Johnston cannula placed in the cranial part of the duodenum just distal to the pylorus. Cannula placement was easily accomplished, and cannulae were tolerated well by the sheep. Volume of effluent produced during the 60- to 120-hour period of diversion ranged from 7.7 to 14.9 L and tended to be greatest during the first 24 hours. All sheep became dehydrated, with mean pcv and plasma total protein concentration increases of 94.2 and 61.7%, respectively. Plasma chloride concentration decreased in linear fashion from a prediversion mean of 113 mEq/L (range, 111 to 117 mEq/L) to an end-point mean of 54 mEq/L (range, 45 to 65 mEq/L). Plasma sodium and potassium concentrations also decreased, though potassium concentration increased terminally. There were rapid increases in arterial blood pH and bicarbonate and base excess concentrations during the first 48 hours after diversion. However, during the final stages of diversion, sheep developed superimposed metabolic acidosis with increased plasma lactate concentration and high anion gap.

Cattle require surgery for small-intestinal problems less frequently than they do for abomasal, forestomach, or large-intestinal problems. Close attention to local vascular anatomy is critical to success when intestinal resection is required. Cows with signs of severe abdominal pain may make rapid recoveries following prompt surgical treatment. This article discusses relevant anatomy of the small intestine and the diagnosis and treatment of intussusception, volvulus, obstruction by incarceration or entrapment, and duodenal obstruction.

SUMMARY Renal electrolyte and net acid excretion were characterized during generation and maintenance of hypochloremic metabolic alkalosis in a ruminant model. Two phases of renal response with regard to sodium and net acid excretion were documented. An initial decrease in net acid excretion was attributable to increase in bicarbonate excretion with associated increase in sodium excretion. As the metabolic disturbance became more advanced, a second phase of renal excretion was observed in which sodium and bicarbonate excretion were markedly decreased, leading to increase in net acid excretion and development of aciduria. Throughout the metabolic disturbance, chloride excretion was markedly decreased; potassium excretion also decreased. These changes were accompanied by increase in plasma renin and aldosterone concentrations. There was apparent failure to concentrate the urine optimally during the course of the metabolic disturbance, despite increasing plasma concentration of antidiuretic hormone.

SUMMARY Data at admission and at surgery were collected on 458 cows with right displacement of the abomasum or abomasal volvulus, to derive multiple logistic regression models for predicting postsurgical outcome (productive, salvaged, or terminal). The derived models contained few and easily obtained variables. The weight associated with each variable was determined objectively. Three admission variables (heart rate, base excess, and plasma chloride concentration), and 5 surgical variables (heart rate, base excess, diagnosis, method of decompression used, and appearance of abomasal serosa) were used in the final models. Predicted outcomes that used the admission and surgical models were closely related with actual outcomes. Total correct classification for satisfactory (productive) versus unsatisfactory outcome (salvaged and terminal) was 78.2% for the admission model and 82.7% for the surgical model. Combining data on cows with productive and salvaged outcomes as satisfactory outcome, and terminal as unsatisfactory outcome, total correct classification was 90.7% for the admission model and 93.2% for the surgical model. Using predicted probabilities, the market value of productive and salvaged cows, and the medical and surgical costs, one can calculate the expected economic value of each outcome. Treatment can be justified if the sum of the expected value of productive and salvaged outcome exceeds the sum of the medical and surgical costs and the expected salvaged value of the cow that was not treated surgically.

Radiographic and surgical findings were compared in 123 cattle suspected of having traumatic reticuloperitonitis. Radiography of the reticulum proved to be a sensitive test for detection of a foreign body (FB). An abnormal FB position on a radiograph was a good predictor of FB perforation. If an FB was fully attached to a magnet, it was unlikely to be perforating the reticular wall. When abnormal reticulum size, abnormal reticulum location, and gas shadows adjacent to the reticulum were found simultaneously on a radiograph, hepatic or perireticular abscess was likely. Reticular radiography proved to be a useful diagnostic aid in cattle suspected of having traumatic reticuloperitonitis.

During a 7-year period, failure of omasal transport attributable to a perireticular abscess was diagnosed in 29 cows. Affected cattle were examined because of anorexia, hypogalactia, and bilateral abdominal distention. The cows were all female Holsteins, 15 months to 10 years old. The abscess was identified during exploratory celiotomy and rumenotomy or at necropsy. Traumatic reticuloperitonitis was believed to be the cause. Twenty-seven cattle (93%) were treated surgically. The abscess was drained into the reticulum or omasum in 25 cows (86%). Twenty-four cows (83%) survived to the time of discharge from the hospital, and 20 (69%) survived for at least 1 year and became productive members of the herd. This is a better survival rate than that reported for other causes of vagal indigestion.

An intramural hematoma involving a 40-cm segment of the distal portion of the jejunum caused intestinal obstruction and colic in a mature mare. The involved intestine was resected, and an end-to-end anastomosis was performed. The mare recovered completely, but 4 years later had colic caused by incarceration and volvulus of the distal portion of the jejunum, involving fibrous abdominal adhesions. The cause of hematoma was not identified; however, rupture of an intramural vessel after migration of Strongylus vulgaris larvae was considered a possibility because of the histologic observation of an intense eosinophilic infiltrate in the region. Vascular rupture caused by blunt abdominal trauma was considered unlikely. Previous descriptions of intramural hematoma in the horse have been confined to the small colon.

Four cows were diagnosed as having volvulus of the distal jejunoileum. Affected cattle became acutely depressed, dehydrated, and tachycardic, all developed abdominal distention, and three of four were in severe pain at the time of admission. Feces were scant or absent. The volvulus was corrected by exteriorizing the small intestine and replacing it in correct position. All four cows recovered without complications and were well 6 months or more following surgery.

A liver abscess resulted in vagal indigestion in 8 dairy cattle. There was cessation of transport of digesta through the omasum. Clinical signs were of variable duration and included abdominal distention and bradycardia. Medical therapy had not been effective. Left paralumbar fossa celiotomy and rumenotomy permitted detection of the liver abscess. A second surgery from a ventral approach allowed drainage of the abscess by insertion of a catheter through the abdominal wall.

Intra-abdominal umbilical cord remnant infections were diagnosed in 21 calves during a 5-year period. The urachal remnant alone was involved in 15 calves, umbilical artery remnant alone in 1 calf, and the umbilical vein remnant alone in 4 calves. Both urachus and umbilical vein were involved in 1 calf. All cases were managed surgically by ventral celiotomy. Infected urachal remnants not extending to the bladder, infected umbilical artery remnant, and infected umbilical vein remnants not extending to the liver were dissected free of surrounding adhered structures, ligated proximal to the infected segment, transected, and removed. Infected urachal remnants extending to the bladder were similarly isolated and removed after resection of the attached bladder apex. Infected umbilical vein remnants extending to the liver were marsupialized. Of 19 calves available for follow-up from 1 to 32 months after surgery, 15 recovered without any postoperative complications, 3 had short-term complications, and 1 calf developed an incisional hernia.