Hamsters are often used to determine the effects of various dietary ingredients on the development of cardiovascular disease (CVD). The study was conducted to obtain baseline data on CVD risk factors and mRNA expression of selected genes in hamsters fed a standard maintenance diet (STD) for 24 wk, beginning when animals were 7 wk old. Plasma triacylglycerol and aortic cholesteryl ester concentrations did not significantly change during the study. Total plasma cholesterol (75.9–127.9 mg/dL), LDL- (3.2–12.2 mg/dL), and HDL- (53.8–98.9 mg/dL) cholesterols increased over the 24wk study. Aortic total cholesterol increased from 9.72 to 12.20 μg/mg protein, whereas aortic cholesteryl ester, a measure of atherosclerosis development, was less than 0.18 μg/mg protein throughout the study. The expression of hepatic endothelin 1, peroxisome proliferator-activated receptor α, and hepatic cholesterol 7-α-hydroxylase mRNA did not change throughout the study, indicating that fatty acid β-oxidation and cholesterol metabolism remained consistent. The mRNA expression of ATP-binding cassette, subfamily B member 11 increased between wk 0 and 8 but then remained unchanged, suggesting increased requirements for cholesterol in early growth. These results indicate that the consumption of a STD does not increase atherosclerotic disease risk factors in golden Syrian hamsters through 31 wk of age.

Clinical decisions and experimental analyses often involve the assessment of hematology and clinical chemistry. Using clinical pathology to assess the health status of NHP in breeding colonies or data from studies than involve pregnancy can often be complicated by pregnancy status. This study had 2 objectives regarding the hematology and clinical chemistry of African green monkeys (AGM, Chlorocebus aethiops sabaeus): 1) to compare pregnant or recently postpartum animals with nonpregnant, nonlactating animals and 2) to create age- and sex-specific reference intervals. Subjects in this study were 491 AGM from the Vervet Research Colony of the Wake Forest University Primate Center. Results indicated that changes in BUN, serum total protein, albumin, ALP, GGT, calcium, phosphorus, sodium, potassium, cholesterol, total CO₂, globulins, lipase, amylase, WBC, neutrophils, lymphocytes, platelets, RBC, Hgb, and Hct occur during pregnancy and the postpartum period. Age- and sex-specific reference intervals consistent with guidelines from the American Society for Veterinary Clinical Pathology were established and further expand the understanding of how to define health in AGM on the basis of clinical pathology. The combination of understanding the changes that occur in pregnancy and postpartum and expansive reference intervals will help guide clinical and experimental decisions.

The study of normal and abnormal development typically requires precise embryonic staging. In mice, this task is accomplished through timed matings and the detection of a copulation plug. However, the presence of a plug is not a definitive indicator of true pregnancy, particularly in inbred mice, in which false-pregnancy rates have been reported to be 50% or higher, depending on the strain. This high rate poses considerable financial and animal use burdens because manipulation of the putative dam is often required before pregnancy can be confirmed by palpation or visual inspection. To address this problem, we examined weight gain in a population of 275 wildtype C57BL/6J mice (age, 12 wk or older) between the time of plug detection and during early embryogenesis (gestational days 7 to 10). In this population, assessing pregnancy according to the presence of a plug alone yielded a 37.1% false-positive rate. Pregnant mice gained an average of 3.49 g, whereas non-pregnant mice gained only 1.15 g. Beginning at gestational day 7.75, implementing an optimal weight-gain discrimination threshold of 1.75 g reduced the false-positive rate to 10.5%, without excluding any pregnant mice. These results were consistent with those from younger (age, 8 wk) wildtype C57BL/6J and FVB/NTac female mice, suggesting broad applicability of this method across age and strain. Our findings provide a simple and effective method for reducing animal use and study costs.

We hypothesized that short-term exposure of mice to vibration within a frequency range thought to be near the resonant frequency range of mouse tissue and at an acceleration of 0 to 1 m/s² would alter heart rate (HR) and mean arterial pressure (MAP). We used radiotelemetry to evaluate the cardiovascular response to vibration in C57BL/6 and CD1 male mice exposed to vertical vibration of various frequencies and accelerations. MAP was consistently increased above baseline values at an acceleration near 1 m/s² and a frequency of 90 Hz in both strains, and HR was increased also in C57BL/6 mice. In addition, MAP increased at 80 Hz in individual mice of both strains. When both strains were analyzed together, mean MAP and HR were increased at 90 Hz at 1 m/s², and HR was increased at 80 Hz at 1 m/s². No consistent change in MAP or HR occurred when mice were exposed to frequencies below 80 Hz or above 90 Hz. The increase in MAP and HR occurred only when the mice had conscious awareness of the vibration, given that these changes did not occur when anesthetized mice were exposed to vibration. Tested vibration acceleration levels lower than 0.75 m/s² did not increase MAP or HR at 80 or 90 Hz, suggesting that a relatively high level of vibration is necessary to increase these parameters. These data are important to establish the harmful frequencies and accelerations of environmental vibration that should be minimized or avoided in mouse facilities.

Sexually mature zebrafish were housed as single male-female pairs with or without plastic vegetation for 1, 5, or 10 d for comparison of whole-body cortisol measured by radioimmunoassay. Individually housed male zebrafish were used as controls. In the fish that were pair-housed without vegetation (NVeg), one animal died in 5 of 24 pairs, and one animal was alive but wounded in an additional pair. No deaths or wounds occurred in the fish that were pair-housed with vegetation (Veg). Cortisol levels did not differ between the treatment groups on day 1. On day 5, cortisol values were higher in the Veg group than in the individually housed fish (P < 0.0005) and the NVeg fish (P = 0.004). On day 10, the relationships were inversed: cortisol levels had risen in the individually housed and NVeg groups and had fallen to baseline levels in the Veg group. Cortisol values on day 10 were lower in the Veg group than in the individually housed (P = 0.004) and NVeg (P = 0.05) groups. Cortisol levels in individually housed male zebrafish increased over time. Although this study did not demonstrate a reduction in cortisol levels associated with providing vegetation, this enrichment prevented injury and death from fighting. These findings show how commonly used housing situations may affect the wellbeing of laboratory zebrafish.

Alopecia has been reported to occur in several species of captive NHP. Much of this research has focused on macaque monkeys; whether other primate species such as baboons are affected similarly is unknown. Because alopecia can be a focus of inspectors and a possible marker of wellbeing, the purpose of the current study was to survey the occurrence of alopecia in 2 baboon populations and to identify potential risk factors. Subjects were 262 group-housed and 279 corral-housed baboons. Alopecia was assessed cage-side (group-housed) and on sedated animals (corral-housed). Although alopecia was mild in both populations, there were significant effects of season and sex. Alopecia was greater in the winter (group-housed) and the fall (corral-housed) and in female baboons. In addition, the group-housed baboons showed a significant negative effect of age and a lesser effect of group size on alopecia. These results demonstrate that variables other than those associated with animal management practices can affect hair loss in baboons.

IACUC protocols can be reviewed by either the full committee or designated members. Both review methods use the principles of the 3 Rs (reduce, refine, replace) as the overarching paradigm, with federal regulations and policies providing more detailed guidance. The primary goal of this study was to determine the frequency of topics discussed by IACUC during full-committee reviews and whether the topics included those required for consideration by IACUC (for example, pain and distress, number of animals used, availability of alternatives, skill and experience of researchers). We recorded and transcribed 87 protocol discussions undergoing full-committee review at 10 academic institutions. Each transcript was coded to capture the key concepts of the discussion and analyzed for the frequency of the codes mentioned. Pain and distress was the code mentioned most often, followed by the specific procedures performed, the study design, and the completeness of the protocol form. Infrequently mentioned topics were alternatives to animal use or painful or distressful procedures, the importance of the research, and preliminary data. Not all of the topics required to be considered by the IACUC were openly discussed for all protocols, and many of the discussions were limited in their depth.

Listeria monocytogenes is an endemic agent in the primate population at the California National Primate Research Center and has been associated with both sporadic cases and a general outbreak of pregnancy failures. The primary objective of this study was to verify the incidence of L. monocytogenes-associated abortion and fetal deaths in the Center's outdoor breeding colony. In addition, we sought to compare the group of female macaques that presented with Listeria-associated abortion with both those with nonlisteria-associated abortion and animals with successful pregnancy outcome. We calculated the incidence of L. monocytogenes-associated abortion and stillbirth by dividing the number of positive L. monocytogenes cultures from aborted fetuses by the number of pregnant female macaques from 1989 through 2009. To compare the pregnancy outcome of female macaques that have presented L. monocytogenes-associated abortion and stillbirth, we created 2 control groups: female macaques with successful pregnancy outcomes during the 1999 breeding season and animals with nonlisteriaassociated pregnancy failure. These macaques were followed for 2 subsequent breeding seasons. The results showed a range in the incidence of L. monocytogenes-associated abortion and stillbirth from 0% to 8.39% throughout the 1989 to 2009 breeding seasons. In addition, the Listeria-associated abortion group did not present statistically significant differences in fertility and abortion rates when compared with the control groups. We conclude that although L. monocytogenes is an endemic agent at the Center's outdoor breeding colony, the agent's incidence varied in significance. Furthermore, an episode of L. monocytogenes-associated abortion did not affect subsequent pregnancies.

Pain management in laboratory animals is generally accomplished by using opioids and NSAIDs. However, opioid use is hindered by controlled substance requirements and a relatively short duration of action. In this study, we compared the analgesic efficacy of firocoxib (a cyclooxygenase-2-selective NSAID) with that of buprenorphine in the mouse model of plantar incisional pain by objective measurement of mechanical allodynia and thermal hyperalgesia using von Frey and Hargreaves equipment, respectively. Our experimental design included 5 treatment groups: firocoxib at 10 mg/kg IP every 24 h (F10 group); firocoxib at 20 mg/kg IP every 24 h (F20); buprenorphine at 0.2 mg/kg SC every 8 h; intraperitoneal normal saline every 24 h; and sham group (anesthesia, no incision) treated with firocoxib at 20 mg/kg IP every 24 h (sham+F20). All mice underwent nociceptive assays at 24 h before and 4, 24, 48, and 72 h after surgery. Buprenorphine alleviated allodynia at all time points after incision. The F10 treatment alleviated allodynia at 4, 24, and 48 h, whereas F20 alleviated allodynia at 24, 48, and 72 h. None of the treatments alleviated thermal hyperalgesia at 4h. Except for F10 and buprenorphine at 24 h, all treatments alleviated thermal hyperalgesia at 24, 48, and 72 h. No significant differences were noted between the 2 doses of firocoxib and buprenorphine regarding mechanical allodynia and thermal hyperalgesia at all time points. In conclusion, the analgesic efficacy of firocoxib is comparable to that of buprenorphine in this mouse pain model.

Tramadol is a centrally acting weak μ opioid agonist that has few of the adverse side effects common to other opioids. Little work has been done to establish an effective analgesic dose of tramadol specific for surgical laparotomy and visceral manipulation in mice. We used general appearance parameters to score positive indicators of pain including posture, coat condition, activity, breathing, and interactions with other mice, activity events (that is, the number of times each mouse stretched up in a 3-min period) used as an indicator of decreased pain, von Frey fibers, and plasma levels of corticosterone to determine whether tramadol at 20, 40, or 80 mg/kg prevented postoperative pain in male and female C57BL/6 mice. A ventral midline laparotomy with typhlectomy was used as a model of postoperative pain. In male mice, none of the markers differed between groups that received tramadol (regardless of dose) and the saline-treated controls. However, general appearance scores and plasma corticosterone levels were lower in female mice that received 80 mg/kg tramadol compared with saline. In summary, for severe postoperative pain after laparotomy and aseptic typhlectomy, tramadol was ineffective in male C57BL/6 mice at all doses tested. Although 80 mg/kg ameliorated postoperative pain in female C57BL/6 mice, this dose is very close to the threshold reported to cause toxic side effects, such as tremors and seizures. Therefore, we do not recommend the use of tramadol as a sole analgesic in this mouse model of postoperative pain.

Each year, millions of rats undergo surgery for research purposes and receive analgesics to alleviate pain. We sought to evaluate the efficacy of common analgesics in tests of hot-plate nociception and postsurgical pain by using the Rat Grimace Scale. Rats received a single dose of one of several drug–dose combinations and were tested by using the hot-plate test (acute pain) or after laparotomy (with either prophylactic or intraoperative analgesic). The efficacy of analgesics for hot-plate pain was generally not predictive of efficacy for surgical pain. Carprofen and ketoprofen were rarely effective in any of the conditions tested. With the exception of the opioid buprenorphine, several of the drugs we tested required higher-than-recommended doses to alleviate pain. Taken together, our data suggest that current analgesic use frequently is insufficient, and many rats may experience significant postsurgical pain even when analgesics are used in commonly recommended doses.

A model system capable of providing clinically relevant analgesic doses with minimal trauma has been elusive in laboratory animal medicine. Our laboratory has developed an orofacial operant pain system that effectively discriminates between nonnoxious and noxious thermal stimuli in rats and mice. Male and female rats (Crl:SD) and mice (Crl:SKR-HR^hr) were trained to perform a task (placing their face through an opening and having their cheeks stay in contact with thermodes) to receive a reward (a solution of sweetened condensed milk). Currently accepted doses of buprenorphine were tested by using a crossover design. Pain was induced in both species by sensitizing the depilated skin over both cheeks with capsaicin cream or by creating a surgical incision (rats only) and then allowing the animals to contact a temperature-regulated thermode while obtaining a reward. Optimal antinociceptive doses included 0.05 and 0.1 mg/kg in male mice but only 0.05 mg/kg in female mice. In rats, optimal antinociceptive doses included 0.03 and 0.05 mg/kg for male rats but only 0.03 mg/kg for female rats. The 2 pain-induction models in rats (capsaicin cream and surgical incision) did not differ. Our orofacial operant pain assay can determine clinically relevant analgesic doses for rodents in a preclinical assay. The automated, investigator-independent nature of the assay, in conjunction with its high sensitivity, makes this method an improvement over traditional noninvasive methods, providing better data for developing optimal analgesic recommendations for rats and mice.

Rectal prolapse is a common clinical problem in laboratory mice. This condition may occur spontaneously, develop after genetic manipulations, result from infections with pathogens such as Citrobacter species, or arise secondary to experimental design such as colitis models. The current standard of care at our institution is limited to monitoring mice until tissue becomes ulcerated or necrotic; this strategy often leads to premature euthanasia of valuable animals prior to the study endpoint. Surgical correction of rectal prolapse is performed routinely and with minimal complications in larger species by using manual reduction with placement of a pursestring suture. In this report, we investigated whether the use of a pursestring suture was an effective treatment for mice with rectal prolapse. The procedure includes anesthetizing mice with isoflurane, manually reducing prolapsed tissue, and placing a pursestring suture of 4-0 polydioxanone. We have performed this procedure successfully in 12 mice. Complications included self-trauma, fecal impaction due to lack of defecation, and mutilation of the surgical site by cage mates. Singly housing mice for 7 d postoperatively, applying multimodal analgesia, and releasing the pursestring when indicated eliminated these complications. The surgical repair of rectal prolapses in mice is a minimally invasive procedure that resolves the clinical symptoms of affected animals and reduces the number of mice that are euthanized prematurely prior to the study endpoint.

Helicobacter species can be found in a wide variety of animals and remain common contaminants of laboratory rodents. Fostering of neonatal pups has been used to eliminate Helicobacter spp. from various laboratory rodents, including laboratory mice and gerbils. Deer mice (Peromyscus maniculatus) from a captive colony enzootic for at least one Helicobacter species were mated, and the pups produced were fostered on laboratory mice 24 h after birth. After 2 rounds of fostering, both foster dams and pups were free of Helicobacter spp. as determined by fecal PCR analysis. Removal of Helicobacter infection through neonatal fostering has not been described previously for Peromyscus maniculatus.