Anesthetic Considerations for Pregnant Laboratory Animals

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-11

Key Takeaways

• Gestation significantly alters maternal physiology, including a 30-50% increase in cardiac output and a decrease in functional residual capacity due to diaphragmatic elevation, accelerating anesthetic induction and hypoxemia risk.
• Anesthetic agents readily cross the placenta, and immature fetal metabolic and excretory pathways can lead to prolonged drug exposure and potential neonatal depression, especially if delivery occurs under anesthesia.
• Aortocaval compression by the gravid uterus in dorsal recumbency reduces venous return and uterine perfusion; lateral or partial lateral recumbency is critical for late-gestation procedures to mitigate maternal hypotension and fetal compromise.
• Anesthetic requirements for inhalant agents are reduced during pregnancy due to hormonal modulation (e.g., progesterone), necessitating careful vaporizer setting adjustments to avoid overdose.
• Monitoring must focus on maternal hypoxemia (SpO₂ and ETCO₂), hypotension (MAP < 60 mmHg in rabbits, < 55 mmHg in rats warrants intervention), and hypothermia (below 36°C in rabbits, 35°C in rats), as these directly impact fetal viability.
• Carbon dioxide pneumoperitoneum for laparoscopic procedures in pregnant animals can cause fetal acidosis and reduced uteroplacental perfusion, requiring minimal insufflation pressures and short procedure durations.

Pregnant laboratory animals present a distinct anesthetic challenge because the physiologic adaptations of gestation alter drug disposition, cardiorespiratory reserve, and procedural risk for both dam and conceptus. This article addresses the anesthetic management of pregnant rodents, rabbits, and swine used in research, with emphasis on the physiological changes that govern anesthetic planning, the fetal consequences of maternal drug exposure, and the monitoring strategies that protect maternal stability. It serves veterinary researchers and clinical veterinarians who design or review protocols involving surgery, imaging, or other procedures under anesthesia during pregnancy. The central clinical question is how to balance maternal anesthetic safety against fetal viability and experimental validity, a balance that shifts with gestational stage, species, and the nature of the intervention.

Anesthesia in pregnant animals is not a single clinical scenario. The gravid state imposes progressive mechanical and hormonal changes that affect every organ system relevant to anesthetic management. The evidence base draws from human surgical literature, laboratory animal pharmacology studies, and species-specific clinical references, and where data are sparse, the clinician must reason from first principles of maternal physiology and drug pharmacology.

At a Glance

Maternal Physiological Changes in Pregnancy

The pregnant animal undergoes cardiovascular, respiratory, and metabolic adaptations that begin early in gestation and intensify as term approaches. Cardiac output rises through increased stroke volume and heart rate, and regional blood flow is redistributed toward the uteroplacental unit. The gravid uterus also compresses the caudal vena cava and aorta when the animal is in dorsal recumbency, particularly in larger species such as swine and rabbits. This aortocaval compression reduces venous return, cardiac output, and uterine perfusion, and it is a recognized cause of maternal hypotension and fetal compromise during surgery. Positioning the animal in lateral or partial lateral recumbency mitigates this effect and should be considered standard practice for late-gestation procedures.

Respiratory changes include a progressive decrease in functional residual capacity as the uterus elevates the diaphragm, alongside an increase in minute ventilation driven by progesterone. The reduced functional residual capacity means that inhalant induction is faster and that apnea or airway obstruction produces hypoxemia more rapidly than in the nonpregnant animal. The increased minute ventilation lowers arterial carbon dioxide tension at baseline, so a "normal" capnographic reading may actually represent relative hypoventilation in the pregnant patient.

Anesthetic requirement for inhalant agents decreases during pregnancy, an effect attributed to progesterone and endogenous neurosteroid modulation of GABAergic tone. The clinician should therefore expect a lower minimum alveolar concentration and adjust vaporizer settings accordingly. The same hormonal milieu increases sensitivity to some injectable agents, although the pharmacokinetic picture is complicated by expanded plasma volume and altered protein binding.

Pharmacokinetic Alterations During Gestation

Pregnancy changes drug absorption, distribution, metabolism, and excretion in ways that are not always predictable from nonpregnant data. Plasma volume expansion dilutes drugs and alters protein binding, while increased renal blood flow and glomerular filtration rate accelerate renal clearance of many compounds. Hepatic drug metabolism shows a mixed pattern, with some cytochrome P450 isoforms induced and others suppressed. The net effect for a given drug cannot be assumed from first principles and must be verified in the species and gestational stage under study.

Anesthesia itself further perturbs drug disposition. A pharmacokinetic study of zidovudine in rats demonstrated that ketamine:acepromazine:xylazine anesthesia decreased total, renal, and non-renal clearance in both pregnant and nonpregnant females, and that cesarean section further reduced renal clearance and volume of distribution. These findings illustrate that the anesthetic state is not pharmacokinetically neutral, and they caution against extrapolating awake pharmacokinetic data to anesthetized pregnant subjects. For research protocols where drug exposure is an experimental endpoint, the anesthetic regimen should be held constant across groups and reported in full.

Fetal Considerations and Placental Transfer

Nearly all anesthetic drugs cross the placenta by passive diffusion, and the fetal compartment is not protected from maternal drug exposure. Fetal hepatic and renal clearance mechanisms are immature, so drugs that are cleared rapidly in the dam may persist in the fetus for extended periods. This is of particular concern when delivery occurs during or shortly after anesthesia, because the neonate must then metabolize and excrete the drug load without mature enzyme systems.

The fetal consequences of maternal anesthesia extend beyond direct drug effects. Maternal hypotension, hypoxemia, hypercapnia, and hypothermia all reduce uteroplacental perfusion and fetal oxygenation. The fetus tolerates some degree of hypoxemia through anaerobic metabolism and preferential shunting of cardiac output to vital organs, but this reserve is limited and is exhausted more quickly under the added stress of anesthetic agents. Fetal acidosis during carbon dioxide pneumoperitoneum has been demonstrated in animal studies, and a clinical review of laparoscopic surgery in pregnant women reported fetal deaths that prompted caution in applying this technique to the gravid patient. For laboratory animal protocols, this evidence supports avoiding pneumoperitoneum in pregnant subjects unless the research question specifically requires it.

Species-Specific Considerations

Rodents, rabbits, and swine differ substantially in their responses to pregnancy and anesthesia, and protocols must be adapted accordingly. Mice and rats have short gestations and large litters, and the timing of procedures relative to implantation and organogenesis determines both fetal sensitivity and the technical feasibility of surgery. Laparoscopy has been described in pregnant mice with accurate counting of gestations as early as one day after implantation, but the same report noted early deaths from hemorrhage and anesthetic overdose, underscoring the narrow margin for error in this species. Swine, by contrast, have a longer gestation and a more developed coagulation system, and they have been used as models for amniotic fluid embolism research because their placental and coagulation physiology resembles that of humans.

The institutional animal care and use program provides the framework within which these procedures are reviewed and approved. The Guide for the Care and Use of Laboratory Animals requires that procedures minimize pain and distress and that anesthetic plans be justified in the protocol. Refinement of anesthetic technique is an explicit goal of the Three Rs framework promoted by the National Center for the Replacement, Refinement and Reduction of Animals in Research, and the veterinary team should document the rationale for agent selection, monitoring, and analgesic provision in the protocol record.

Pre-Anesthetic Assessment and Risk Stratification

The pre-anesthetic evaluation of a pregnant laboratory animal begins with confirming gestational stage, litter size, and maternal health status. Gestational age determines which physiological adaptations are active and which fetal risks dominate. In rodents, the second half of gestation carries the greatest hemodynamic and respiratory burden, while early gestation presents higher risk for fetal resorption and teratogenic effects. The institutional veterinary team should review the approved animal care and use protocol to confirm that the procedure is justified at the chosen gestational stage and that refinements have been considered, as outlined in NC3Rs guidance on refinement and welfare.

Physical examination should focus on body weight trajectory, hydration status, mucous membrane color, and thoracic auscultation. A pregnant animal that has lost weight, shows tachypnea at rest, or has poor fur condition is a poorer anesthetic candidate and the procedure should be reconsidered. Baseline temperature matters because pregnant animals, particularly rabbits and guinea pigs, have limited thermoregulatory reserve and hypothermia develops rapidly under anesthesia.

Risk stratification should integrate three domains: maternal physiological status, fetal developmental stage, and procedural invasiveness. A laparotomy in a late-gestation rat carries higher risk than a short imaging procedure under light sedation in the same animal. The assessment should also consider whether the dam will be recovered and carried to term or whether the procedure is terminal with fetal harvest. This distinction changes the acceptable risk profile substantially. For survival surgery, the AVMA professional practice resources emphasize that perioperative pain management and physiologic support must be planned before the procedure begins.

Selection of Anesthetic Agents and Protocols

Agent selection balances maternal safety, fetal depression, and the specific requirements of the procedure. No single agent is universally safe across all laboratory species and gestational stages. The table below summarizes the safety profiles of commonly used agents during pregnancy.

Current formularies and institutional drug protocols must be consulted for species-specific doses. The table is a decision framework, not a dosing reference.

For survival surgery in rodents, inhalant anesthesia with isoflurane is the most common choice because recovery is rapid and depth is adjustable. The addition of an opioid or nonsteroidal anti-inflammatory drug for perioperative analgesia must account for gestational changes in drug disposition. The MSD Veterinary Manual provides species-specific pharmacology guidance that should inform agent selection.

For rabbits, the combination of ketamine and dexmedetomidine followed by inhalant maintenance is widely used, but the rabbit's limited ability to vomit and its obligate nasal breathing require careful airway positioning. Guinea pigs present additional challenges because they are prone to ileus and have high calcium demands in late gestation. For all species, the chosen protocol should be tested in a pilot animal when feasible, particularly when the procedure is novel to the team.

Monitoring Parameters and Physiologic Support

Monitoring in pregnant laboratory animals must detect the failure modes most likely to cause maternal or fetal loss: hypoxemia, hypotension, hypothermia, and hypoglycemia. Standard monitoring includes respiratory rate and pattern, heart rate and rhythm, mucous membrane color, capillary refill time, and rectal temperature. Pulse oximetry is useful but readings can be unreliable in small species with rapid heart rates and poor probe placement. Capnography, when available, provides a more accurate assessment of ventilation, particularly during laparoscopy or when the abdomen is distended.

Blood pressure monitoring is technically challenging in small rodents but should be attempted in larger species such as rabbits and guinea pigs. Indirect methods using a Doppler probe or oscillometric cuff can detect trends even when absolute values are imprecise. A falling blood pressure in the face of stable heart rate suggests vasodilation, often from inhalant overdose or from aortocaval compression by the gravid uterus. Repositioning the animal to a lateral or slight tilt can relieve uterine compression of the caudal vena cava.

Temperature support is mandatory. Warm circulating water blankets, forced-air warmers, and insulated wraps should be used from induction through recovery. The dam's thermoregulatory set point is altered by anesthetics, and fetal temperature follows maternal temperature closely. Hyperthermia must also be avoided because it increases fetal oxygen demand and can trigger maternal tachypnea.

Blood glucose should be checked before and during prolonged procedures, especially in small rodents with limited glycogen reserves. Dextrose supplementation in intravenous fluids may be indicated, but excessive glucose can cause fetal hyperinsulinemia and postnatal hypoglycemia. Balanced electrolyte solutions are preferred for maintenance.

Procedural Considerations for Abdominal Surgery

Laparotomy in a pregnant animal requires attention to uterine handling, hemostasis, and the risk of fetal trauma. The gravid uterus is friable and easily bruised. Surgical instruments should be handled gently, and moistened laparotomy sponges should protect exposed viscera. The surgeon must decide whether to exteriorize the uterus or manipulate it in situ. Exteriorization improves visualization but increases heat loss and traction on the uterine vessels.

Laparoscopy in pregnant animals carries specific risks. A retrospective review of laparoscopic surgery during pregnancy reported fetal deaths in a series of human patients and cited animal studies demonstrating fetal acidosis during carbon dioxide pneumoperitoneum. The authors advised caution when considering laparoscopic surgery in pregnant patients. In laboratory animals, the same concern applies: carbon dioxide insufflation raises intra-abdominal pressure, compresses the uterine vasculature, and can cause fetal acidosis. If laparoscopy is necessary, insufflation pressures should be kept as low as possible and the procedure time minimized. A mouse laparoscopy technique was reported as feasible in pregnant mice, but the authors noted an initial learning curve with hemorrhage and anesthetic overdose as early complications. This underscores that operator experience is a major determinant of outcome.

For cesarean section, the timing of fetal delivery relative to anesthetic depth is critical. Deep maternal anesthesia depresses fetal respiration and neonatal vigor. The surgical team should be prepared for neonatal resuscitation, including gentle stimulation, airway clearance, and thermal support. In rodents, removing pups from the uterus while the dam is still under anesthesia requires coordination between the surgeon and the anesthetist to minimize the interval between uterine incision and pup stimulation.

Documentation and Record Keeping

Anesthetic records for pregnant animals should capture the same parameters as for non-pregnant animals, with additional fields for gestational age, litter size, and any fetal or neonatal outcomes. The record should note the time of induction, maintenance agent concentrations, physiologic parameters at regular intervals, and all drugs administered with routes and times. Any adverse events, such as hypotension, hypothermia, or prolonged recovery, should be documented with the corrective actions taken.

The Guide for the Care and Use of Laboratory Animals requires that veterinary records document animal welfare and that procedures be performed in accordance with the approved protocol. For survival surgery, the record should also include postoperative monitoring plans, analgesic administration, and criteria for humane intervention. For terminal procedures, the record should document the method of euthanasia and confirm that death occurred before recovery from anesthesia.

Accurate records serve two purposes: they support the individual animal's care and they contribute to the institutional knowledge base. When a complication occurs, the record allows the team to identify whether the cause was anesthetic, surgical, or related to the animal's preoperative status. This information should feed back into protocol refinement, consistent with the NC3Rs emphasis on continuous improvement of procedures.

Recognized Complications and Early Detection

Pregnant laboratory animals under anesthesia can deteriorate along predictable pathways. The most consequential failure modes are maternal hypoxemia, hypotension, hypothermia, and anesthetic overdose, each with downstream fetal consequences.

Maternal hypoxemia is the earliest and most dangerous complication. Reduced functional residual capacity and increased oxygen consumption shorten the safe apnea window. Pulse oximetry trends matter more than single readings. A progressive decline in SpO₂ despite apparent adequate ventilation should prompt immediate assessment of airway patency, oxygen supply, and breathing circuit integrity. Capnography showing rising end-tidal CO₂ with falling SpO₂ suggests hypoventilation, whereas falling CO₂ with falling SpO₂ points to circuit disconnection or airway obstruction.

Hypotension in pregnancy is multifactorial. Aortocaval compression from the gravid uterus reduces venous return in larger species such as rabbits and mini-pigs. Deep anesthetic planes compound this by suppressing sympathetic tone. Non-invasive oscillometry may under-read in small mammals, so direct arterial pressure measurement is preferred for procedures exceeding 30 minutes in rabbits and larger species. A mean arterial pressure below 60 mmHg in rabbits or below 55 mmHg in rats warrants immediate intervention: reduce vaporizer setting, administer warmed crystalloid boluses, and reposition the animal to offload the abdomen.

Hypothermia develops rapidly in small pregnant animals because their surface area to mass ratio is high and the gravid uterus increases heat loss. Shivering is suppressed by anesthesia, and fetal thermoregulation is entirely dependent on maternal temperature. A fall below 36 °C in rabbits or 35 °C in rats increases anesthetic requirements, slows drug metabolism, and impairs coagulation. Continuous rectal or esophageal temperature monitoring with active warming devices is mandatory for any procedure exceeding 20 minutes.

Anesthetic overdose in pregnant animals is insidious because drug requirements are reduced. The classic error is dosing by body weight without accounting for the altered volume of distribution and reduced clearance during gestation. Pharmacokinetic studies in rats demonstrate that anesthesia with ketamine, acepromazine, and xylazine decreases total, renal, and non-renal clearance of concurrently administered drugs, meaning drug accumulation occurs faster than expected effects of gender, pregnancy, and anesthesia on the pharmacokinetics of zidovudine in rats. Early detection relies on frequent assessment of palpebral and pedal reflexes, jaw tone, and respiratory rate. A progressive bradycardia with slow, shallow breathing is the terminal warning.

Common Errors and Corrective Actions

Less experienced clinicians frequently misjudge the depth of anesthesia in pregnant animals. The gravid state reduces minimum alveolar concentration, so an animal that appears lightly anesthetized by reflex testing may already be dangerously deep. The corrective action is to titrate to the lowest effective plane and to use agent-specific monitoring instead of relying on a single reflex.

A second recurring error is delaying surgery until the animal is profoundly hypotensive. Pregnant animals compensate for early hypovolemia with peripheral vasoconstriction, masking blood loss until decompensation is abrupt. Serial assessment of mucous membrane color, capillary refill time, and pulse quality should be performed every five minutes during abdominal procedures. A pale, slow capillary refill with a thready pulse demands immediate fluid resuscitation before proceeding.

A third error involves the pneumoperitoneum used for laparoscopic procedures. Animal studies have demonstrated fetal acidosis during carbon dioxide pneumoperitoneum, and clinical reviews in humans have reported fetal deaths following laparoscopic surgery in pregnancy laparoscopic surgery during pregnancy. In laboratory rodents, laparoscopy can be performed safely after an initial learning curve, but hemorrhage and anesthetic overdose remain the principal causes of mortality mouse laparoscopy. The corrective action is to maintain the lowest insufflation pressure that permits visualization, limit procedure duration, and monitor end-tidal CO₂ continuously to detect absorption of insufflated gas.

Limitations of Current Evidence

The evidence base for anesthetic management of pregnant laboratory animals is fragmented. Most published data derive from small studies in rats, mice, and mini-pigs, with limited direct transferability across species. Pharmacokinetic studies during gestation are scarce, and the interaction between pregnancy, anesthesia, and drug disposition is understood for only a handful of agents effects of gender, pregnancy, and anesthesia on the pharmacokinetics of zidovudine in rats.

Expert opinion diverges on several points. Whether inhalant or injectable anesthesia is safer for the fetus remains unsettled. Some clinicians favor isoflurane or sevoflurane for their rapid adjustment and predictable recovery, while others prefer injectable combinations for field settings where vaporizers are unavailable. The evidence does not clearly favor either approach, and institutional experience often dictates practice.

The coagulation changes of late pregnancy are also incompletely characterized. Studies in pregnant mini-pigs show that infusion of amniotic fluid or fetal membranes alters platelet counts and coagulation parameters meconium and amniotic fluid embolism: effects on coagulation in pregnant mini-pigs, but the relevance of these findings to routine anesthetic management is unclear. Clinicians should interpret coagulation data cautiously and avoid extrapolating from non-pregnant reference intervals.

Referral, Consultation, and Regulatory Reporting

Referral to a veterinary anesthesiologist or laboratory animal specialist is warranted when a pregnant animal requires prolonged anesthesia, when cardiovascular instability develops despite corrective measures, or when the procedure involves significant blood loss. Specialist consultation is also appropriate when the investigator requests a novel agent or technique for which gestational safety data are absent.

Institutional animal care and use committee involvement is required before any procedure that deviates from an approved protocol. The Guide for the Care and Use of Laboratory Animals specifies that anesthesia and analgesia plans must be reviewed and approved, and that unanticipated pain, distress, or death must be reported. The NC3Rs resources on refinement provide practical guidance for reducing anesthetic morbidity in breeding and pregnant animals.

Regulatory reporting obligations vary by jurisdiction. Unexpected death during anesthesia, particularly when it occurs in a protocol that did not anticipate this outcome, should be reported to the institutional animal care and use committee. In production animal settings, withdrawal periods for anesthetic agents in pregnant animals destined for human consumption must be verified against current label and formulary references, and local veterinary authorities should be consulted where doubt exists. The AVMA practice resources and WOAH terrestrial animal health standards offer additional guidance on professional obligations and international welfare expectations.

Frequently Asked Questions

How should I adjust the anesthetic plan when only injectable agents are available for pregnant rodents?

Injectable anesthesia remains the standard for many laboratory rodent protocols, particularly when vaporizer access is limited. Ketamine-based combinations are commonly used, but pregnancy alters drug disposition. In rats, anesthesia with ketamine, acepromazine, and xylazine decreases total, renal, and non-renal clearance of concurrently administered drugs, an effect that can prolong recovery and increase variability in plasma concentrations. When using injectable protocols in pregnant animals, reduce the initial dose by 10 to 20 percent, monitor depth closely, and expect prolonged effect. Always consult a current formulary for species-specific dose ranges. The Guide for the Care and Use of Laboratory Animals requires that anesthetic depth be verified before any surgical incision, regardless of agent class.

What monitoring adaptations are needed when standard equipment such as pulse oximetry is unavailable?

When electronic monitoring is absent, rely on serial assessment of pedal withdrawal, palpebral reflexes, respiratory rate and pattern, mucous membrane color, and capillary refill time. In pregnant animals, abdominal distension can restrict diaphragmatic excursion, so observe thoracic and abdominal wall movement separately. Weigh animals before anesthesia and use a precision scale to track blood loss on gauze and sponges, as gravid uterine tissue is highly vascular. The NC3Rs guidance on refinement emphasizes that regular, structured observation by trained personnel can substitute for electronic monitors when equipment is limited. Document each parameter at five-minute intervals. If the animal is too small for a pulse oximeter probe, consider Doppler ultrasound for heart rate assessment where available.

How does the anesthetic approach differ for pregnant rabbits compared with pregnant rodents?

Rabbits present distinct challenges. They are obligate nasal breathers, so endotracheal intubation requires a laryngoscope and small-diameter cuffed tube, and the oropharynx is narrow with a large tongue. Gastric stasis is common in late pregnancy, increasing regurgitation risk during induction. Rabbits also have high vagal tone, making them prone to bradycardia under deep anesthesia. Preoxygenation is strongly advised. The MSD Veterinary Manual provides species-specific guidance on rabbit anesthesia, including the need for careful positioning to avoid compression of the caudal vena cava by the gravid uterus. Recovery should occur in a quiet, warm environment with the head elevated. Unlike rodents, rabbits require fasting of only two to four hours to reduce hypoglycemia risk.

What should I document when anesthesia is administered to a pregnant animal for a survival procedure?

Record the gestational age or stage, maternal body weight, anesthetic agents and doses, induction and recovery times, all monitoring parameters at defined intervals, estimated blood loss, and any complications. Note the route and volume of any fluids administered. Document the rationale for the anesthetic protocol chosen, particularly if it deviates from the standard institutional protocol. The AVMA practice resources emphasize that complete anesthesia records support both animal welfare and regulatory compliance. If the procedure is terminal, record the method of euthanasia and confirm cardiac arrest before fetal collection if fetuses are needed. For survival studies, document postoperative analgesia, housing modifications, and any observed pregnancy outcomes such as litter size or gestational length.

How do I explain the added risks of anesthesia in pregnant animals to an investigator or supervisor?

Frame the discussion around fetal and maternal physiology instead of abstract risk. Explain that pregnancy increases cardiac output, reduces functional residual capacity, and alters drug clearance, all of which change anesthetic requirements. Cite the observation that even routine procedures such as laparoscopy in pregnant mice can be performed safely after an initial learning curve, but that operator experience and careful monitoring are decisive factors. Reference the National Research Council Guide requirement that procedures be refined to minimize pain and distress. Recommend a pre-procedure meeting to review the protocol, expected outcomes, and contingency plans for maternal or fetal complications. Emphasize that transparency about risk improves study quality and animal welfare.

When is it appropriate to postpone or cancel anesthesia in a pregnant laboratory animal?

Postpone elective procedures if the animal shows signs of systemic illness, poor body condition, or abnormal pregnancy progression such as vaginal discharge or prolonged gestation. If the dam is near term and the procedure is not urgent, delay until after parturition. For non-survival procedures, confirm the scientific justification for using a pregnant animal and that no non-pregnant alternative exists. The WOAH terrestrial animal health standards and the NC3Rs framework both support the principle that procedures should be refined or replaced where possible. If equipment failure occurs after induction, stabilize the animal and either complete the procedure quickly or recover her, depending on surgical stage and stability. Document the decision and its rationale in the anesthesia record.

Related Clinical & Scientific Guides

• Refining IACUC Protocols to Minimize Animal Pain and Distress
• Health Monitoring Programs for Laboratory Animal Facilities
• Anesthetic Risk Assessment in Laboratory Animals: Preoperative Evaluation

References and Further Reading

• Laparoscopic surgery during pregnancy.. 1996.
• Effects of gender, pregnancy, and anesthesia on the pharmacokinetics of zidovudine in rats.. 1995.
• Administration of autologous fetal membranes: Effects on the coagulation in pregnant mini-pigs.. 2000.
• Mouse laparoscopy.. 1999.
• Developmental exposure to a commercial PCB mixture (Aroclor 1254) produces a persistent impairment in long-term potentiation in the rat dentate gyrus in vivo.. 1999.
• Meconium and amniotic fluid embolism: effects on coagulation in pregnant mini-pigs.. 1999.
• Guide for the Care and Use of Laboratory Animals, 8th Edition. National Academies Press, 2011.
• NC3Rs Resources on Replacement, Reduction and Refinement. NC3Rs.
• MSD Veterinary Manual, Professional Edition. MSD Veterinary Manual.

Related Articles

• Anesthesia Monitoring Parameters for Laboratory Animals
• Anesthetic Considerations for Immunodeficient Mice
• Anesthesia for Laboratory Rabbits: Protocols and Monitoring
• Anesthesia Machine Safety Checks for Laboratory Animal Use
• Anesthesia Equipment for Small Laboratory Animals: Setup and Maintenance

This article is educational professional reference material for veterinary audiences. It is not a substitute for veterinary diagnosis, individual clinical judgment, current product labeling, or applicable regulatory requirements.