Spared nerve injury decreases motivation in long-access homecage-based operant tasks in mice.

ABSTRACT: Neuropathic pain causes both sensory and emotional maladaptation. Preclinical animal studies of neuropathic pain-induced negative affect could result in novel insights into the mechanisms of chronic pain. Modeling pain-induced negative affect, however, is variable across research groups and conditions. The same injury may or may not produce robust negative affective behavioral responses across different species, strains, and laboratories. Here, we sought to identify negative affective consequences of the spared nerve injury model on C57BL/6J male and female mice. We found no significant effect of spared nerve injury across a variety of approach-avoidance conflict, hedonic choice, and coping strategy assays. We hypothesized these inconsistencies may stem in part from the short test duration of these assays. To test this hypothesis, we used the homecage-based Feeding Experimentation Device version 3 to conduct 12-hour, overnight progressive ratio testing to determine whether mice with chronic spared nerve injury had decreased motivation to earn palatable food rewards. Our data demonstrate that despite equivalent task learning, spared nerve injury mice are less motivated to work for a sugar pellet than sham controls. Furthermore, when we normalized behavioral responses across all the behavioral assays we tested, we found that a combined normalized behavioral score is predictive of injury state and significantly correlates with mechanical thresholds. Together, these results suggest that homecage-based operant behaviors provide a useful platform for modeling nerve injury-induced negative affect and that valuable pain-related information can arise from agglomerative data analyses across behavioral assays-even when individual inferential statistics do not demonstrate significant mean differences.

Intra-annual density fluctuations in tree rings are proxies of air temperature across Europe.

Intra-Annual Density Fluctuations (IADFs) are an important wood functional trait that determine trees' ability to adapt to climatic changes. Here, we use a large tree-ring database of 11 species from 89 sites across eight European countries, covering a climatic gradient from the Mediterranean to northern Europe, to analyze how climate variations drive IADF formation. We found that IADF occurrence increases nonlinearly with ring width in both gymnosperms and angiosperms and decreases with altitude and age. Recently recorded higher mean annual temperatures facilitate the formation of IADFs in almost all the studied species. Precipitation plays a significant role in inducing IADFs in species that exhibit drought tolerance capability, and a growth pattern known as bimodal growth. Our findings suggest that species with bimodal growth patterns growing in western and southern Europe will form IADFs more frequently, as an adaptation to increasing temperatures and droughts.

Effectiveness of school-based interventions targeting physical activity and sedentary time among children: a systematic review and meta-analysis of accelerometer-assessed controlled trials.

OBJECTIVES: To date, no meta-analysis has examined the influence of specific intervention characteristics in the overall effectiveness of school-based interventions measured only with accelerometer devices. Thus, the main purpose of this systematic review and meta-analysis was to evaluate the overall and specific variables of the effectiveness of school-based interventions assessed with accelerometer devices among children aged 5-12 years. STUDY DESIGN: A systematic review and meta-analysis to assess the effectiveness of school-based interventions. METHODS: Studies published in English, French and Spanish from five electronic databases between January 2010 and December 2021 were identified. Intervention designs with control group measure that assessed daily moderate-to-vigorous physical activity (MVPA) and sedentary time (ST) with accelerometer devices in children aged 5-12 years were included. PROSPERO ID: CRD42022326859. RESULTS: A total of 24 trials comprising of 19,487 children (51.3% girls) were included. Intervention studies were ineffective for improving daily MVPA (Hedges' g = 0.07, 95% confidence interval [CI] -0.03 to 0.17; I2 = 84.80%) but were effective for reducing ST (g = -0.08, 95% CI -0.12 to -0.03; I2 = 20.94%). Also, subgroup analyses for MVPA revealed that when studies had two intervention components (g = 0.21, 95% CI 0.06-0.36; I2 = 77.67%), and high quality (g = 0.12, 95% CI 0.01-0.22; I2 = 88.30%) they were effective. CONCLUSION: School-based interventions have been effective to reduce children's daily time spent in ST. There is no evidence of overall effectiveness of school-based interventions for enhancing daily MVPA in children. Nevertheless, improving the quality of interventions and interventions with two components are effective to increase students' daily MVPA.

Increased levels of soluble fms-like tyrosine kinase-1 are associated with adverse outcome in pregnant women with COVID-19.

OBJECTIVE: In addition to the lungs, the placenta and the endothelium can be affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) are markers of endothelial dysfunction and could potentially serve as predictors of severe coronavirus disease 2019 (COVID-19). We aimed to investigate the association of serum concentrations of sFlt-1 and PlGF with the severity of COVID-19 in pregnancy. METHODS: This was a prospective cohort study carried out in a tertiary care hospital in Mexico City, Mexico. Symptomatic pregnant women with a positive reverse-transcription quantitative polymerase chain reaction test for SARS-CoV-2 infection who fulfilled the criteria for hospitalization were included. The primary outcome was severe pneumonia due to COVID-19. Secondary outcomes were intensive care unit (ICU) admission, viral sepsis and maternal death. sFlt-1 levels were expressed as multiples of the median (MoM). The association between sFlt-1 and each adverse outcome was explored by logistic regression analysis, adjusted for gestational age for outcomes occurring in more than five patients, and the predictive performance was assessed by receiver-operating-characteristics-curve analysis. RESULTS: Among 113 pregnant women with COVID-19, higher sFlt-1 MoM was associated with an increased probability of severe pneumonia (adjusted odds ratio (aOR), 1.817 (95% CI, 1.365-2.418)), ICU admission (aOR, 2.195 (95% CI, 1.582-3.047)), viral sepsis (aOR, 2.318 (95% CI, 1.407-3.820)) and maternal death (unadjusted OR, 5.504 (95% CI, 1.079-28.076)). At a 10% false-positive rate, sFlt-1 MoM had detection rates of 45.2%, 66.7%, 83.3% and 100% for severe COVID-19 pneumonia, ICU admission, viral sepsis and maternal death, respectively. PlGF values were similar between women with severe and those with non-severe COVID-19 pneumonia. CONCLUSION: sFlt-1 MoM is higher in pregnant women with severe COVID-19 and has the capability to predict serious adverse pregnancy events, such as severe pneumonia, ICU admission, viral sepsis and maternal death. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Shock hemorrágico tras artroplastia total de cadera / Hemorrhagic shock after total hip arthroplasty

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Laparoscopic graduated cardiomyotomy with anterior fundoplication as treatment for achalasia: experience of 48 cases. / Cardiomiotomía graduada con funduplicatura anterior laparoscópica en acalasia, experiencia de 48 casos.

INTRODUCTION AND AIMS: At the Upper Gastrointestinal Tract Clinic of the Hospital General de Mexico, achalasia treatment has been standarized through strictly graduated cardiomyotomy. This procedure guarantees a complete myotomy for the satisfactory resolution of dysphagia, a characteristic symptom of achalasia. To ensure the inclusion of the entire lower esophageal sphincter, an 8cm Penrose drain is placed at the surgical site 6cm above the gastroesophageal junction and 2cm in a caudal direction, for accurate laparoscopic measuring. The aim of our study was to evaluate the results of this technique. MATERIALS AND METHODS: A descriptive, retrospective, longitudinal, and observational study was conducted on a cohort of patients diagnosed with achalasia at the Upper Gastrointestinal Tract Clinic of the Hospital General de México "Dr. Eduardo Liceaga". RESULTS: The study included 48 patients, 40 of whom had no prior surgical treatment and 8 that presented with recurrence. Forty-seven patients (97.9%) underwent a laparoscopic procedure and conversion to open surgery was required in 2 of them (4.25% conversion rate). Postoperative progression was satisfactory in all cases, with mean oral diet commencement at 52h and mean hospital stay of 5.7 days. No recurrence was registered during the mean follow-up period of 35.75 months and there were no deaths. CONCLUSIONS: Laparoscopic graduated (strictly measured) cardiomyotomy with anterior fundoplication is a reproducible, efficacious, and safe option for the surgical treatment of achalasia.

Gradient induced artifacts in simultaneous EEG-fMRI: Effect of synchronization on spiral and EPI k-space trajectories.

The nature of the gradient induced electroencephalography (EEG) artifact is analyzed and compared for two functional magnetic resonance imaging (fMRI) pulse sequences with different k-space trajectories: echo planar imaging (EPI) and spiral. Furthermore, the performance of the average artifact subtraction algorithm (AAS) to remove the gradient artifact for both sequences is evaluated. The results show that the EEG gradient artifact for spiral sequences is one order of magnitude higher than for EPI sequences due to the chirping spectrum of the spiral sequence and the dB/dt of its crusher gradients. However, in the presence of accurate synchronization, the use of AAS yields the same artifact suppression efficiency for both pulse sequences below 80Hz. The quality of EEG signal after AAS is demonstrated for phantom and human data. EEG spectrogram and visual evoked potential (VEP) are compared outside the scanner and use both EPI and spiral pulse sequences. MR related artifact residues affect the spectra over 40Hz (less than 0.2 µV up to 120Hz) and modify the amplitude of P1, N2 and P300 in the VEP. These modifications in the EEG signal have to be taken into account when interpreting EEG data acquired in simultaneous EEG-fMRI experiments.

Risk factors for recurrence and incontinence after anal fistula surgery.

OBJECTIVE: Fistula-in-ano continues to raise problems that require important therapeutic decisions. Our aim was to evaluate its recurrence and incontinence risk factors. METHOD: We analysed a series of 279 patients who had undergone anal fistula surgery with long-term follow-up. RESULTS: 42.7% of the fistulae were considered complex and 46% had been referred from other institutions. There was delayed healing or recurrence in 7.2% patients, which appeared at a median of 4 months. The factors associated with recurrence were the type of fistula (extrasphincteric/suprasphincteric), nonidentification of internal opening (IO), recurrent or complex fistulae (CF), and associated chronic abscess. Only CF and nonidentification of IO were statistically significant in the multivariate analysis. Preoperative incontinence was a risk factor for postoperative incontinence, as were suprasphincteric, recurrent and CF. The age and gender of the patient did not influence postoperative continence, nor did the surgeon or surgical technique appear as a risk factor, although after excluding preoperative incontinent patients, fistulotomy was the technique that showed a higher risk of incontinence. Multivariate analysis only confirmed previous incontinence as a RF. CONCLUSION: The overall recurrence rate is acceptable, but high fistulae continue to be difficult to treat. IO identification is also essential for obtaining good results. It is important to identify the patients with preoperative incontinence as they are at a greater risk of deterioration after surgery.

Prospective study of artificial anal sphincter and dynamic graciloplasty for severe anal incontinence.

BACKGROUND AND AIMS: Dynamic graciloplasty and artificial anal sphincter are two options for refractory incontinence, the efficacy of which was compared in a prospective study. PATIENTS AND METHODS: Between November 1966 and June 1998, 16 patients were operated on (artificial anal sphincter 8, dynamic graciloplasty 8). Four consecutive operations with each technique were performed by two colorectal surgeons (one initiated the study with the neosphincter and the other with dynamic graciloplasty). Two independent observers assessed postoperative results at 4-month intervals. Patients were followed up to January 2001, with a median (interquartile range) of 44 (13) months and 39 (15) months for the nesophincter and the dynamic graciloplasty, respectively. RESULTS: Fourteen patients had complications. In the immediate postoperative period; there were eight cases of wound healing-related problems (four in the graciloplasty group). Perineal infection occurred in one patient in the graciloplasty group. At follow-up there were 11 complications (6 in the neosphincter group). Four patients undergoing neosphincter implantation had erosion or pain at the cuff site and had the implant removed (a new device was reimplanted in one). Four patients undergoing dynamic graciloplasty had the stimulator removed. Postoperatively the neosphincter was associated with a significantly lower score on the continence grading scale of the Cleveland Clinic Florida than graciloplasty. CONCLUSION: The artificial anal sphincter is a more convenient technique than dynamic graciloplasty for institutions treating small number of patients. However, technical failures and complications during follow-up that require reoperation are very high in both types of treatments.

Utilidad de la ecografía anorrectal en la enfermedad de Crohn perianal / Utility of anorectal echography in perianal Crohn's disease

Introducción. La ecografía anorrectal (EAR) es una exploración sencilla, cuyo valor en el diagnóstico de la patología anorrectal está altamente contrastado en la bibliografía. El propósito de este estudio ha sido examinar la utilidad de la EAR en pacientes con enfermedad de Crohn (EC) intestinal que presentan algún tipo de manifestación perianal de su enfermedad. Material y métodos. Entre octubre de 1996 y febrero de 1999 se han realizado un total de 18 EAR en 16 pacientes diagnosticados de EC intestinal y con sospecha clínica de presentar algún proceso anorrectal. Utilizamos un ecógrafo B&K Medical con un transductor rotatorio de 360°. El motivo más frecuente de petición de EAR fue la valoración de proctalgia de etiología incierta (5 casos, 28 por ciento). Otros motivos fueron: fístulas anales (4 casos, 22 por ciento), sospecha de absceso anal (3 casos, 17 por ciento), control evolutivo (3 casos, 17 por ciento), incontinencia fecal (2 casos, 11 por ciento) y sepsis perianal (un caso, 6 por ciento). Resultados. La orientación diagnóstica del clínico coincidió con los hallazgos ecográficos en 12 casos (67 por ciento). Una imagen compatible con absceso fue reconocida en 10 casos (55 por ciento), dos de ellos ya sospechados clínicamente y los otros ocho fueron hallazgos asociados fundamentalmente a fístulas y proctalgias de etiología no filiada. Se detectaron defectos esfinterianos en los 2 casos de incontinencia fecal y en otros 2 pacientes fue un hallazgo casual. En el caso de las fístulas anorrectales la EAR permitió conocer de modo más preciso la relación de las mismas con los esfínteres. Conclusiones. La EAR es de gran utilidad en la EC perianal ya que es capaz de detectar con precisión los defectos esfinterianos y los abscesos anales, motivo por el que resulta de gran valor en el caso de proctalgias o abscesos no sospechados clínicamente. Creemos que la EAR debe ser realizada después del examen rectal, la rectoscopia o la colonoscopia en estos enfermos (AU)

Estudio cooperativo nacional sobre la utilización de aspiración nasogástrica y alimentación precoz en cirugía colorrectal / Nationwide cooperative study on the utilization of nasogastric aspiration and early feeding in colorectal surgery

Introducción. El objetivo de este estudio fue evaluar la seguridad y eficacia de la sonda nasogástrica y la alimentación oral precoz en cirugía colorrectal. Pacientes y métodos. Hemos realizado un estudio multicéntrico, prospectivo y no aleatorizado que incluía a pacientes sometidos a cirugía colorrectal electiva. Los grupos de estudio fueron: grupo 1: sonda nasogástrica postoperatoria; grupo 2: sin sonda nasogástrica y dieta oral progresiva habitual, y grupo 3: sin sonda nasogástrica y alimentación oral precoz. Las variables analizadas fueron: presencia de náuseas y vómitos, necesidad de colocación de la sonda nasogástrica, tolerancia a la dieta oral, día de comienzo de peristalsis audible, inicio de tránsito para gases y heces, uso de fármacos antieméticos, grado subjetivo de bienestar postoperatorio y aparición de complicaciones. Resultados. Al final del estudio se recibieron 406 encuestas. La distribución ha sido: grupo 1: 200 pacientes (49,3 por ciento), grupo 2: 152 pacientes (37,4 por ciento) y grupo 3: 54 pacientes (13,3 por ciento). La aparición de peristaltismo audible, el inicio de tránsito a gases y heces, así como la tolerancia a la alimentación oral, fueron más precoces en los grupos 2 y 3 (sin sonda nasogástrica) que en el grupo 1, con diferencias estadísticamente significativas (p < 0,05). El grado de comodidad postoperatoria fue mayor en los grupos sin sonda nasogástrica. Las complicaciones aparecieron de forma similar en todos los grupos. Conclusiones. La alimentación oral precoz y la restricción del uso de sonda nasogástrica en cirugía colorrectal electiva son seguras y sin desventajas en relación con el uso sistemático de SNG y dieta oral progresiva (AU)

Inactivation of bovine herpesvirus 1 in semen using a hyperimmune egg yolk semen extender.

Hyperimmune egg yolk semen extender was used for the inactivation of bovine herpesvirus (BHV-1) in experimentally infected bovine semen. As much as 5 x 10(4) TCID50/ml of virus was inactivated in semen as assayed by tissue culture. Moreover the hyperimmune egg yolk semen extender did not produce any adverse effect on the quality of the semen after being frozen/thawed in comparison with normal egg yolk semen extender (P > 0.05). The hyperimmune egg yolk semen extender is considered an important tool for containing the spread of BHV-1 from infected semen.

Evaluation of the effects of different trypsin treatments on semen quality after BHV-1 inactivation, and a comparison of the results before and after freezing, assessed by a computer image analyzer.

Semen infected experimentally with infectious bovine rhinotracheitis virus (BHV-1) was treated with trypsin at concentrations of 0.30%, 0.25% and 0.15%, with or without (w or w/o) trypsin inhibitor in order to render the semen virus free. The trypsin treatments (at 0.30% and 0.25% by concentration) inactivating the virus up to 10(4) TCID50/ml, and its effects on semen quality were assessed weekly from the 1st to 20th week after being frozen. The following parameters were determined using a computerized semen analysis system (Hamilton Thorn motility analyzer, HTM): total motility, progressive motility and linearity of sperm cells. The results showed that the total and progressive motility of sperm cells were reduced in frozen/thawed semen, principally in the semen treated with trypsin at concentrations of 0.30%. Moreover, the plasma membranes were damaged by trypsin treatments (0.30% by concentration), as determined by the hypoosmotic swelling test (HOS test). These findings suggest that trypsin treatments were effective against the virus however the effects on semen quality and the possibility of a decrease in semen fertility were clear. Trypsin treatment could be recommended at a maximum concentration of 0.25% (w/o trypsin inhibitor) on semen with a high concentration and high motility values of spermatozoa before freezing.

Anorectal function in patients with complete rectal prolapse. Differences between continent and incontinent individuals.

AIMS: A study is made of the alterations in anorectal physiology among rectal prolapse patients, evaluating the differences between fecal continent and incontinent individuals. PATIENTS AND METHODS: Eighteen patients with complete rectal prolapse were divided into two groups: Group A (8 continent individuals) and Group B (10 incontinent women), while 22 healthy women were used as controls (Group C). Clinical exploration and perineal level measurements were performed, along with anorectal manometry, electrophysiology, and anorectal sensitivity to electrical stimuli. RESULTS: The main antecedents of the continent subjects were excess straining efforts, while the incontinent women presented excess straining and complex deliveries. Pathological perineal descent was a frequent finding in both groups, with a hypotonic anal canal at rest (p < 0.001 vs controls) and at voluntary squeezing (p < 0.001 vs controls). In turn, the incontinent patients exhibited a significantly lower anal canal pressure at rest than the continent women (p < 0.05). There were no significant differences between Groups A and C in terms of pudendal motor latency, though latency was significantly longer in Group B than in the controls (p < 0.01). Moreover, pudendal neuropathy was more common, severe and often bilateral in Group B. There were no differences in rectal sensation to distention or in terms of the volumes required to relax the internal anal sphincter. In turn, both prolapse groups exhibited diminished anal canal and rectal sensitivity to electrical stimuli. CONCLUSIONS: Patients with rectal prolapse exhibit a hypotonic anal canal at rest, regardless of whether they are continent to feces or not. Continent patients have less pudendal neuropathy and therefore less pressure alterations at voluntary sphincter squeeze than incontinent individuals.

Can digital examination substitute anorectal manometry for the evaluation of anal canal pressures?

INTRODUCTION: Anorectal manometry provides objective information on the sphincter function of the anal canal. However, in many centers sphincter function is evaluated by digital examination, due to the unavailability of manometry. OBJECTIVE: A study is made to correlate the sensitivity and specificity of a quantitative digital examination in the analysis of sphincter tone with the pressures recorded by manometry, and to examine the capacity of both techniques to discriminate continent subjects and incontinent patients. PATIENTS AND METHODS: A total of 191 patients were divided into three groups: control (C), obstructive defecation (OD) and fecal incontinence (FI). Subjective quantitative digital evaluation of anal tone was performed on a scale of 0 to 5 points at rest, and 0 to 10 points at squeeze. A correlation analysis was performed, and the sensitivity and specificity of each fecal incontinence diagnostic test was determined. RESULTS: Digital examination found rectal tone to be diminished in elderly patients. A significant correlation was established between the digital and manometric tone readings, both at rest and at squeeze. Both techniques showed a low anal sphincter pressure in the FI group versus the C and OD groups. Differences in tone were recorded between the C and OD groups with manometry, but not with digital examination. The latter was in turn found to be more sensitive but less specific than manometry in differentiating between fecal continence and incontinence. CONCLUSIONS: Although digital examination does not substitute anorectal manometry, a good correlation exists between the two techniques. In this sense, digital examination may afford an approximate clinical evaluation of some fecal continence mechanisms in those centers where manometry is not available.

Effect of porcine reproductive and respiratory syndrome virus (PRRSV) on development of porcine fertilized ova in vitro.

Fertilized pig ova, collected from 14 estrus-synchronized gilts 32 h after presumed ovulation were microinjected or cultured for 72 h in Beltsville Embryo Culture Medium-3 with or without Porcine Reproductive and Respiratory Syndrome Virus (PRRSV). To detect virus in the samples, virus isolation of swine alveolar macrophage, Reverse Transcriptase Polymerase Chain Reaction and Fluorescent Antibody techniques were employed. Microinjection or incubation of embryos with PRRSV did not significantly inhibit development of the porcine embryos in vitro when compared with that of controls (P = 0.75 and P = 0.14, respectively). Although either 10 to 20 TCID50 were microinjected or large concentrations of virus were used for embryo exposure by incubation, PRRSV was not detected in association with the embryos. It is concluded based on the experiments reported here that 4- to 16-cell stage pig embryos are not susceptible to productive infection with PRRSV in vitro.

Phylogenetic relationships of european strains of porcine reproductive and respiratory syndrome virus (PRRSV) inferred from DNA sequences of putative ORF-5 and ORF-7 genes.

The complete ORF-5 gene and a fragment of the ORF-7 gene from 14 different European porcine reproductive and respiratory syndrome virus (PRRSV) isolates were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), and their nucleotide sequences were determined. The ORF-7 gene displayed nucleotide and amino acid identities of 94.1-99.6% and 95.3-100% among isolates from different countries. The ORF-5 gene showed higher nucleotide (87.1-99.2% identity) and amino acid (-88% identity) variability. The resulting sequences were aligned with other European and North American PRRSV strains and phylogenetic relationships among these strains were established by the maximum parsimony method. The phylogenetic trees inferred from both genes were in agreement and showed that European and North American PRRSV strains clearly represent two different genotypes. According to both trees, there is a perfect correlation between strains and the countries in which they were isolated. Additionally, the phylogenetic position of European and North American PRRSV strains within the recently proposed family Arteriviridae was also analyzed.

Exposure of gilts in early gestation to porcine reproductive and respiratory syndrome virus.

Twenty-five gilts without measurable serum antibody titres to porcine reproductive and respiratory syndrome virus (PRRSV) were identified and 16 were inoculated with PRRSV at seven, 14 or 21 days of gestation and killed 20 to 22 days later to determine the effect of the virus on their embryos. The remaining nine gilts were not exposed to PRRSV, but were killed at the same stages of gestation. The gilts were observed for clinical signs of infection and the gilts and their embryos were tested for PRRSV and homologous antibodies. The infection was demonstrated by the re-isolation of the virus and its detection by the reverse transcriptase polymerase chain reaction in serum and other tissue samples from the inoculated gilts, and also by seroconversion. However, the gilts remained healthy throughout the study, except for one which was depressed and anorexic for two days. Two of the litters from the gilts challenged with PRRSV on day 14 of gestation contained one and three infected live embryos; the other embryos from these two litters did not contain detectable virus, although most of the embryos in one of the litters were dead. The other nine litters from the gilts challenged with PRRSV and the control litters, showed no evidence of infection.

Rapid and high sensitivity test for direct detection of bovine herpesvirus-1 genome in clinical samples.

A procedure for direct detection of the BHV-1 genome in clinical samples, including semen, was developed. The method is based on the PCR amplification of a highly conserved DNA fragment within the glycoprotein gI sequence of the virus (323 bp between nt 1491 to nt 1814). The method is rapid and highly specific for all 27 subtypes assayed, which are included in the clinical and genetically different groups of BHV-1. The viral origin of the PCR product was assessed by Southern hybridization, with an internal probe. The method for DNA isolation from clinical samples included a fast extraction procedure with Chelex 100 resin allowing the loading of larger amounts of DNA in the PCR and in turn increasing the sensitivity of the method of detection. The level of sensitivity achieved by PCR was in the range of 1 TCID(50). This PCR assay may be an useful tool for BHV-1 monitoring in semen banks at low cost.