Effects of photoperiod on growth, carcass composition, prolactin, growth hormone and cortisol in prepubertal and postpubertal Holstein heifers

Effects of photoperiod on growth, carcass composition and serum concentrations of prolactin, growth hormone and cortisol were determined in prepubertal and postpubertal Holstein heifers. Forty-two prepubertal (avg body wt 84 +/- 3.0 kg) and 42 postpubertal (avg body wt 303 +/- 7.1 kg) Holstein heifers were utilized. Ten prepubertal and 10 postpubertal heifers were slaughtered before treatment began to obtain initial carcass data. The remaining 32 prepubertal and 32 postpubertal heifers were paired by body weight and randomly assigned to short-day (8 h of light: 16 h of dark) or long-day (16 h of light: 8 h of dark) photoperiods. After exposure to treatments for an average of 139 d, 10 prepubertal and 10 postpubertal heifers from each photoperiod treatment were slaughtered. In prepubertal heifers, photoperiod did not affect (P greater than .10) average daily body weight gain, carcass weight, carcass composition, accretion of carcass fat and carcass protein, or serum concentrations of prolactin, growth hormone or cortisol. However, prepubertal heifers exposed to long-day photoperiods had reduced (P less than .01) urinary N tau-methylhistidine excretion compared with heifers given short-day photoperiods. Postpubertal heifers exposed to short-day photoperiods had greater average body weight daily gain than animals exposed to long-day photoperiods. Although there was no effect of photoperiod (P greater than .10) on carcass or fat depot weights, postpubertal heifers exposed to short days had greater (P = .06) percentages of fat and reduced (P = .07) percentages of protein in the soft tissue of the 9-10-11 rib sections. Fat accretion was greater (P less than .05) in carcasses of postpubertal heifers exposed to short days than heifers given long-day photoperiods, but there was no effect (P greater than .10) of photoperiod on protein accretion. Photoperiod did not affect serum concentrations of growth hormone and cortisol, but serum prolactin tended (P less than .10) to be greater in postpubertal heifers exposed to long days. Under the conditions of this experiment, we conclude that exposure to short-day photoperiods stimulated body weight gain and fat accretion in postpubertal but not prepubertal Holstein heifers.     

Volvulus of the Distal Part of the Jejunoileum in Four Cows

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.     

Prevalence and effects of intramammary infection in beef cows

Prevalence and effects of intramammary infection in 322 beef cows was determined during three calving intervals. Intramammary infection was confirmed in 37% of cows and 18.1% of quarters. Coagulase-positive staphylococci accounted for 17.9% of infections with Staphylococcus aureus isolated from 7.1% of cows. Coagulase-negative staphylococci and micrococci accounted for the remainder of infectious organisms. Butterfat and total protein levels were reduced 27.3 (P less than .05) and 25.5% (P less than .01), respectively, in milk from quarters infected with S. aureus. Somatic cell counts were elevated (P less than .001) with 3,827 X 10(3) cells/ml for S. aureus-infected quarters as compared with 555 X 10(3) cells/ml for uninfected quarters. Somatic cell counts were negatively correlated with 210-d calf weaning weights. Staphylococcus aureus-infected cows weaned calves weighing 19.1 kg less (P less than .01) than uninfected cows. At a present market value of $1.65/kg, economic losses were placed at $31.43/calf from cows infected with S. aureus in one or more quarters.     

Acid-base status and electrolyte alterations associated with diarrhea in non-suckling horses

A retrospective search of medical records of 56 adult horses with diarrhea of variable duration disclosed a variety of blood gas and electrolyte abnormalities at the time of admission. The acid-base and electrolyte disturbances were analyzed and classified according to the duration of diarrhea. In horses with acute diarrhea (duration <6 days) the most common disorder was combined anion gap metabolic acidosis and metabolic alkalosis (72%)characterized by significant hyponatremia, hypochloridemia, and hyperkalemia. The most severe acidemia was found in horses with diarrheas of intermediate duration (1–2 weeks). In this group hyperchloremic metabolic acidosis was commonly found (43%). In horses with diarrhea of long duration (>4 weeks) blood gas and electrolyte values were usually within normal limits. Although the above findings suggest differing therapeutic approaches might be based on the duration of the diarrhea, many cases differed markedly from the mean with respect to their underlying disturbances and, therefore, optimal fluid therapy should be based on the patient's blood gas and electrolyte status.     

Suspected chlorpyrifos toxicosis in a llama, and plasma pseudocholinesterase activity in llamas given chlorpyrifos

Five days after treatment with chlorpyrifos, a 1.5-year-old male llama was unable to stand, had saliva flowing from its mouth, and had constricted pupils, hyperglycemia, a metabolic acidosis, and a plasma pseudocholinesterase activity of 111 IU/L. Mean (+/- 1 SD) plasma pseudocholinesterase activity of 29 healthy llamas was 233.76 +/- 51.55 IU/L. Five to 8 days after topical application of chlorpyrifos (25 mg/kg of body weight) to 3 healthy llamas, the pseudocholinesterase activity decreased to 38% to 62% of pretreatment (base-line) activity and returned to within 90% of base-line activity by the 36th to 48th day after treatment.     

Effect of electroimmobilisation on ovine plasma concentrations of beta-endorphin/beta-lipotrophin, cortisol and prolactin

The effect of electroimmobilisation on the plasma concentrations of beta-endorphin/beta-lipotrophin (beta-EP/beta-LPH), cortisol and prolactin (PRL) has been assessed in sheep. Serial blood samples were collected from control and electroimmobilised animals during the first and fourth of a series of four repeated treatments over two days. After electroimmobilisation the mean (+/- SEM) plasma concentrations of beta-EP/beta-LPH increased significantly from 132 +/- 19 pg ml-1 to 545 +/- 111 pg ml-1; the plasma concentrations of cortisol also increased significantly from 22.3 +/- 3.5 ng ml-1 to 108.0 +/- 12.9 ng ml-1. There was no significant change in plasma PRL concentrations after electroimmobilisation and also no significant difference between the plasma concentrations of PRL in the control and electroimmobilised animals. There was no significant difference between the effects of the first and fourth exposure to electroimmobilisation on the plasma concentrations of beta-EP/beta-LPH, cortisol and PRL. These results suggest that the endocrine response to electroimmobilisation may be specific to the pituitary-adrenal axis.     

Primary isolation and identification of avian rotaviruses from turkeys exhibiting signs of clinical enteritis in a continuous MA 104 cell line

Avian rotaviruses were isolated from turkeys with enteritis using MA 104 cell line. MA 104 cells were suitable for primary isolation and propagation of avian rotaviruses. Trypsin appeared essential for the enhancement of infectivity and the occurrence of cytopathic effect (CPE). Serum neutralization (SN), electron microscopy (EM), and analysis of genomic RNA were done to identify and confirm the identity of rotaviruses. Electrophoretic migration patterns of genomic RNA from avian rotaviruses were examined, and they were compared with those from mammalian rotaviruses. The migration patterns differed between these groups.     

Bilateral hydronephrosis secondary to endometriosis managed by endoscopic ureteral stent placement in a captive Guinea baboon (Papio papio)

Spontaneous endometriosis is an estrogen-dependent, progressive and painful disease that affects a variety of nonhuman primates, including several species of baboons (Papio sp.). This case documents multimodal management of severe endometriosis in a captive female baboon within a zoological institution. An 18-yr-old, intact female Guinea baboon (Papio papio) was found to have an enlarged uterus. Fifteen months post ovariohysterctomy, scarring associated with endometrial tissue resulted in ureteral strictures, bilateral hydronephrosis, and azotemia. Cystoscopic placement of bilateral ureteral stents with fluoroscopy was performed and resulted in short-term clinical improvement. The animal's condition declined and euthanasia was elected 4 mo after ureteral stent placement. Severe endometriosis with secondary inflammation resulting in bilateral hydroureter and hydronephrosis, as well as concurrent cystitis, ureteritis, and pyelonephritis were confirmed at necropsy. Despite possible complications, ureteral stents can be considered a useful therapeutic option in patients with ureteral disease.