Lab

Tal Raz's Lab - Reproductive Biology & Theriogenology

About the lab

Dr. Raz is a reproductive biologist and a theriogenologist. Since 2013 he is a researcher (PI), leading the Laboratory of Reproductive Biology & Theriogenology, at the Koret School of Veterinary Medicine, the Hebrew University, Israel.
The overall goal of the lab is to advance knowledge and propose novel therapeutic approaches focused on the function of the ovary, the uterus and the placenta, via a multidisciplinary approach that combines basic research and clinical methods.
Currently, there are 3 major research topics in the lab.
1) The association between animal welfare and the reproductive system, including the development of non-surgical sterilization methods
2) Improving reproductive health and fertility in dairy cows
3) Placenta physiology and pathology (IUGR and preeclampsia).

Featured projects (1)

Project
The spread and undesirable reproduction of feral dogs and cats is a major problem in both urban and rural settings, which impacts animal welfare and health, as well as public health due to the transmission of zoonotic diseases to humans. Currently, surgical sterilization (neutering/castration) is the most common practice; however, these techniques are expensive, require surgical and anesthetic supplies and equipment, and can be performed only by veterinarians. Therefore, a practical solution to the millions of feral cats and dogs which are confined and euthanized has unfortunately not been found. In the Raz's Laboratory, we aim to improve the welfare of dogs and cats by exploring non-surgical sterilization methods for fertility prevention. As part of that, we perform an extensive study to characterize the field condition of stray dogs in Israel. In addition, in studies collaborated with the laboratory of Prof. Eyal Klement from the Koret School of Veterinary Medicine, we have performed several studies in order to characterize the needs and the demographic parameters that are relevant to the future application of non-surgical sterilization methods under field conditions of free-rooming cats.

Featured research (7)

Endometritis is a uterine disease of dairy cows causing substantial negative effects on reproductive performance and inflicting considerable economic losses. It is typically diagnosed by endometrial cytology evaluation and commonly named cytological endometritis (CEM). In most previous studies, cows were defined as CEM positive if the proportion of polymorphonuclear cells (%PMN) in their endometrial cytology was above a pre-set threshold. Thresholds were established based on CEM diagnosis in association with reproductive performance, typically analyzed by a single reproductive parameter and calculated for all cows together. Our objective was to examine whether primiparous and multiparous cows should optimally be diagnosed for CEM by different %PMN thresholds and sampling timings, using a combination of several reproductive performance parameters. Two endometrial cytobrush cytology samples were collected from Holstein-Friesian dairy cows (n = 415; 269 multiparous; 146 primiparous), at 30-40 d in milk (DIM) and 60-70 DIM, and %PMN were evaluated microscopically (blindly; Diff-Quick stain, Medi-Market). The %PMN thresholds were set at ≥1% to ≥10%, ≥15%, and ≥20%, and accordingly, for each of the thresholds, several reproductive performance parameters were compared between CEM-positive versus CEM-negative cows. Upon application of several analytic approaches, our results indicated that optimal CEM diagnosis should be performed by different criteria in primiparous and multiparous cows: in primiparous cows at 30-40 DIM, using a threshold of ≥7%PMN, and in multiparous cows at 60-70 DIM, using a threshold of ≥4%PMN. Such a diagnostic approach provides a comprehensive view of the reproductive prognosis of CEM-positive primiparous and multiparous cows, which is pertinent information for researchers, veterinarians, and farmers.
Importance The SARS CoV2 alpha variant posed increased risk for COVID19 complications in pregnant women. However, its impact on the maternal humoral response and placental IgG transport remains unclear. Objective To characterize the maternal humoral waning and neonate immunity acquired during the third COVID19 wave in Israel, dominated by the Alpha variant, as compared to earlier Wildtype infections and humoral response to vaccination across gestation. Design Maternal and fetal blood serum were collected at delivery since April 2020 from parturients. Sera IgG and IgM titers were measured using the Milliplex MAP SARS CoV2 Antigen Panel supplemented with additional HA coupled microspheres. Setting A nationwide multicenter cohort study on SARS CoV2 infections and vaccination during pregnancy. Participants Expectant women presenting for delivery were recruited at 8 medical centers across Israel and assigned to 3 primary groups. 157 SARS CoV2 positive and 125 fully vaccinated during pregnancy, and 212 unvaccinated noninfected controls matched to the infected group by BMI, maternal age, comorbidities and gestational age. Eligibility criteria included pregnant women without active COVID19 disease, age over 18 years and willingness to provide informed consent. Main Outcomes and Measures Pregnant womens humoral response is dependent on the SARS CoV2 strain. Results The humoral response to infection as detected at birth, showed a gradual and significant decline as the interval between infection or vaccination and delivery increased. Significantly faster decay of antibody titers was found for infections occurring during the third wave compared to earlier infection or vaccination. Cord blood IgG antigens levels correlated with maternal IgG. However, cord IgG HA variance significantly differed in SARS CoV2 infections as compared to the other groups. No sexual dimorphism in IgG transfer was observed. Lastly, high fetal IgM response to SARS CoV2 was detected in 17 neonates, all showing elevated IgM to N suggesting exposure to SARS CoV2 antigens. Conclusions and Relevance Infections occurring during the third wave induced a faster decline in humoral response when compared to Wildtype infections or mRNA BNT162b2 vaccination during pregnancy, consistent with a shift in disease etiology and severity induced by the Alpha variant. Vaccination policies in previously infected pregnant women should consider the timing of exposure along pregnancy as well as the risk of infection to specific variants of concern.
Background: The significant risks posed to mothers and fetuses by COVID-19 in pregnancy have sparked a worldwide debate surrounding the pros and cons of antenatal SARS-CoV-2 inoculation, as we lack sufficient evidence regarding vaccine effectiveness in pregnant women and their offspring. We aimed to provide substantial evidence for the effect of BNT162b2 mRNA vaccine versus native infection on maternal humoral, as well as transplacentally acquired fetal immune response, potentially providing newborn protection. Methods: A multicenter study where parturients presenting for delivery were recruited at 8 medical centers across Israel and assigned to three study groups: vaccinated (n=86); PCR confirmed SARS-CoV-2 infected during pregnancy (n=65), and unvaccinated non-infected controls (n=62). Maternal and fetal blood samples were collected from parturients prior to delivery and from the umbilical cord following delivery, respectively. Sera IgG and IgM titers were measured using Milliplex MAP SARS-CoV-2 Antigen Panel (for S1, S2, RBD and N). Results: BNT162b2 mRNA vaccine elicits strong maternal humoral IgG response (Anti-S and RBD) that crosses the placenta barrier and approaches maternal titers in the fetus within 15 days following the first dose. Maternal to neonatal anti-COVID-19 antibodies ratio did not differ when comparing sensitization (vaccine vs. infection). IgG transfer rate was significantly lower for third-trimester as compared to second trimester infection. Lastly, fetal IgM response was detected in 5 neonates, all in the infected group. Conclusions: Antenatal BNT162b2 mRNA vaccination induces a robust maternal humoral response that effectively transfers to the fetus, supporting the role of vaccination during pregnancy. Funding: Israel Science Foundation KillCorona grant 3777/19 (to MN, MK, SY, AM). Research grant from the Weizmann Institute Fondazione Henry Krenter (to MN).
Overpopulation of free-roaming cats is a major problem leading to negative impacts on animal health and welfare, public nuisance, transmission of zoonotic diseases, and well-documented harm to wildlife. Surgical sterilization had failed to provide a practical solution to free-roaming cats' overpopulation under field conditions; therefore, efficient and safe non-surgical immunocontraception methods are aspired. Rabies is a deadly virus that may infect people and animals. However, the safety and efficacy of combined vaccination with anti-GnRH and rabies vaccines in feral cats, which often suffer from disrupted health conditions and experienced high stress level, has never been studied. Therefore, our objective was to examine the short-term safety and efficacy of anti-GnRH vaccine (Gonacon), in combination with rabies vaccine in female feral cats. Mature feral female cats were captured and divided into the following groups: (I) GonaconX1-Rabies: queens vaccinated with both Gonacon and rabies (n = 5); (II) GonaconX2-Rabies: queens vaccinated twice with Gonacon (3 weeks apart) and with Rabies (n = 4); (III) OVx-Rabies: queens ovariohysterectomized and vaccinated with rabies (n = 4); (IV) Intact-Rabies: queens vaccinated against rabies and remained intact (n = 3). Comprehensive veterinary examinations and blood tests were performed every 2 weeks for 14 weeks. Data were analyzed by Repeated-Measures-ANOVA or Fisher-Exact-Test. There were neither systemic nor local adverse reactions at the vaccination sites. Blood count (PCV, TS, RBC, HGB, HCT, WBC) and chemistry (Total protein, Total globulin, Albumin, Urea, Creatinine, Creatine kinase, Bilirubin, GGT, ALT, AST) analyses revealed no differences among groups. There were no differences in serum rabies antibodies titers among groups, and queens kept a protective titer (>0.5 IU/mL) starting at 2–4 weeks after vaccination. Anti-GnRH antibodies were detected in all Gonacon-vaccinated queens, excluding one queen (GonaconX2-Rabies group). Anti-müllerian hormone serum concentrations reduced significantly after ovariohysterectomy, as well as gradually following vaccination with Gonacon, but it remained high in intact queens. Evaluation of vaginal cytology and ovarian histology suggested that reproductive cyclicity was suppressed in Gonacon-vaccinated queens. Our results support the conclusion that in the short term, the combined vaccination with Gonacon and rabies is safe and effective in female feral cats. However, further long-term studies are warranted to test this immunologic regimen in feral cats.
Food animal welfare is an issue of great concern, as society has a responsibility for animals under human care. Pork is the most consumed meat worldwide, with more than a billion pigs being slaughtered globally every year. Still, in most countries, sows are restrained in farrowing crates throughout lactation. In these crates, sows are confined with bars to an area that is just slightly larger than their body. Thus, moving and turning around, grooming, or expressing other natural behaviors are typically impossible. In this study, we utilized a simple and practical modification of conventional farrowing crates to designed farrowing pens, by removable confinement bars, which provide the flexibility to change the housing system from one to another. Our objective was to examine the parameters of production and hair cortisol concentrations after different restraint periods during lactation. Analyses included data from 77 sows and their 997 piglets. Sows were housed in farrowing crates, but the confinement bars were removed after different periods, from 3 days post-farrowing to full restraint. For certain analyses, sows were grouped into Short or Long Restraint groups (3–10 days vs 13–24 days, respectively). Multiple linear regression revealed that for any additional day in restraint of the sows, piglets' weaning rate decreases by 0.4% (P

Lab head

Tal Raz
Department
  • Koret School of Veterinary Medicine
About Tal Raz
  • I am a reproductive biologist and a veterinarian with expertise in the area of mammalian reproduction. Since 2013 I am an Assistant Professor leading the Laboratory of Reproductive Biology and Theriogenology at the Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Israel. I am currently on sabbatical in the USA (Utah), and enrolled in the MS Bioinformatic program (Krieger School of Arts and Sciences; AAP) at John Hopkins University.

Members (8)

Rahul Dutta
  • Hebrew University of Jerusalem
Elad Eliahoo
  • Hebrew University of Jerusalem
Maor Kedmi
  • Hebrew University of Jerusalem
Shiri Novak
  • Hebrew University of Jerusalem
Ron Sicsic
  • Hebrew University of Jerusalem
Shaked Druker
  • Hebrew University of Jerusalem
Nathalie Weizmann
  • Hebrew University of Jerusalem
Noa Semel
  • Hebrew University of Jerusalem
Nathalie Weizmann
Nathalie Weizmann
  • Not confirmed yet
Ron Sicsic
Ron Sicsic
  • Not confirmed yet
Noa Semel
Noa Semel
  • Not confirmed yet
Hagai Akiva
Hagai Akiva
  • Not confirmed yet
mormiri.benchaim@mail.huji.ac.il
mormiri.benchaim@mail.huji.ac.il
  • Not confirmed yet