Red wolf vaccination study at PDZA

We have a guest blogger this week, Dr. Kadie Anderson, DVM at Point Defiance Zoo & Aquarium!  Dr. Anderson has graciously blogged for us previously on reproductive research that is ongoing through the Red Wolf Species Survival Plan (RWSSP) and Point Defiance Zoo & Aquarium (PDZA). 

Just like our pets, red wolves require routine and preventive care.  Most animal health programs recommend vaccinating for certain infectious disease and the veterinary arm of the RWSSP is no different.  Red wolves in the RWSSP and wild populations’ are vaccinated to protect these endangered animals against disease such as parvovirus, distemper, and rabies. 

As the field of zoo and wildlife medicine continues to advance, veterinarians often have to extrapolate treatment and management plans from models developed in similar domestic species, e.g. dogs, and apply them to non-domestic canids.   Red wolves have been vaccinated for parvovirus, canine distemper, adenovirus, and rabies on an annual basis without evidence that the vaccines conveyed adequate immunity and how long the vaccines would last.  Recent research showing that domestic dogs could maintain protective titers to distemper and parvovirus for longer than one year (and as long as 3 years) sparked the RWSSP’s interest in determining the efficacy and duration of these vaccines in non-domestic canids such as the red wolf.    

To understand this study, a brief review of how vaccines cause protective immunity is warranted.  It may come as a surprise that the first dose of many vaccines is not protective against disease.  The first dose of vaccine primes the immune system to begin developing a response to the antigen, or disease agent.  This initial response generates antibodies but usually not in sufficient quantities to generate a protective response or titer (amount of antibody).  The second and third boosters of vaccine again stimulate the immune system to generate a larger amount of antibody with each dose, eventually reaching an endpoint (for most animals) which is considered protective.  These antibodies, called IgG, circulate in the immune system for an unknown length of time waiting to react to an infection.

In 2007, PDZA received funding from PDZA’s Conservation Committee to begin a multi-year study to determine whether the vaccination interval could be increased from one year to three years for canine distemper and parvovirus vaccine products.  Facilities from around the nation participated in the study, with the majority of study animals coming from PDZA’s off-site breeding facility.  A total of 32 animals entered the study.  In order to enter the study, wolves must have completed a neonatal series of vaccines and received their annual booster vaccination.  Serology was performed to determine endpoint titers for parvovirus, distemper, and adenovirus on an annual basis.  A positive endpoint titer (considered protective) was extrapolated from that which was considered positive in domestic dogs.  While results of adenovirus protection were unclear due to varying vaccination histories and products used, 100% of wolves developed and maintained a protective titer over three years to distemper virus and ~97% of wolves developed and maintained a positive titer to parvovirus over the three year study. 

Approximately 8 week old pup receiving first series of vaccinations.
Photo: W. Waddell/PDZA

Pup receiving third vaccination at around 12 weeks of age.
Photo: W. Waddell/PDZA

These findings have changed the preventive medicine guidelines for red wolves in the RWSSP, to align with recommendations for domestic dogs, where the initial vaccination series occurring in neonates is followed with a booster at 1 year of age then triennially thereafter.  Increased vaccination intervals reduce handling and associated stress in the wolves, and minimize the risks associated with vaccination.  It is hoped that this information can also be utilized to aid in the management and risk reduction for wild red wolves, to minimize potential losses to infectious disease. 

Lincoln Park Zoo projects and #11353

A few months ago we mentioned that the Red Wolf Recovery Program and Red Wolf Species Survival Plan (RWSSP) partners from Point Defiance Zoo & Aquarium (Tacoma, WA) and Lincoln Park Zoo (Chicago, IL) received three grants from for projects that will further the conservation of the endangered red wolf.   The awards grants annually to a variety of conservation and research programs worldwide, and is supported by generous contributions from PDZA, Point Defiance Zoo Society, and the Point Defiance American Association of Zoo Keepers chapter. 

One of these projects is to develop baseline red wolf population viability models of both wild and zoo-based populations.  Population viability analysis (PVA) will help us determine red wolf population dynamics and understand trends in both populations, greatly enhancing our collective ability to conserve the species and advance red wolf recovery goals.  As the program grows and faces new challenges, these models can be used to help predict extinction risks and effects of different adaptive management strategies.

PVA working group: David, Nicole, Joe, Lisa, Sarah, and Will. Photo: B.Bartel/USFWS

Last week, David and Becky from the Red Wolf Recovery Program along with Will, the RWSSP Coordinator from PDZA, landed in the Windy City to meet with collaborators at the Alexander Center for Applied Population Biology including Lisa, the Vice President of Conservation and Science, and fellow researchers, Joe and Nicole.  Sarah, the director of the Population Management Center at Lincoln Park Zoo, also serves as an advisor in population biology on the RWSSP Advisory Board.  We discussed the different data sets for the zoo and wild populations and considered various model structures and formats we could use for this work.  

We also got to tour the red wolf exhibit in the Pritzker Family Children’s Zoo.  There are currently three females at the zoo, 11353 born in 2004, and two of her daughters born in 2010. Red wolf 11353 is actually an important wolf in the captive breeding program.  She’s had three successful litters with 21 pups, which are now distributed across 6 different RWSSP sites. Additionally, 6 of her pups were fostered into the wild population in 2009 and 2010.  The Red Wolf Recovery Program is still actively monitoring 2 of these individuals.  Interestingly, one of 11353's pups fostered in 2009 (11737) has since fathered two sets of pups in wild (in 2012 and 2013).  This spring we actually fostered a pup into his 2013 litter—a fostering full circle!

Stay tuned for more updates on this research!

Foster pup with new packmates (11737's offspring). Photo: B. Bartel/USFWS.

A big thank you to Lisa, Sarah, Joe, and Nicole for hosting us last week!

2013 Pup Totals

Pup numbers are in for 2013. Thirty-four pups in seven litters were found in the restored red wolf population in northeastern North Carolina.  Twenty-one pups in four litters were also born in three captive facilities participating in the Red Wolf Species Survival Plan: six at Jackson Zoo, five at Alligator River National Wildlife Refuge, and 11 at Northwest Trek (two litters).  We did observe some pup mortality in the captive populations this year, with only one of five surviving at Alligator River and three surviving at Jackson Zoo.  These losses were attributed to both viral and bacterial infections.  The lone survivor from the Alligator River litter was fostered into a wild pack in May.

Wild pup in northeastern North Carolina.  Photo by A.Beyer/USFWS.

 

Wild pups in northeastern North Carolina.  Photo by A.Beyer/USFWS.

 

Captive pups at Jackson Zoo. Photo by Jackson Zoo.

For more information on the 2013 whelping season, you can read the news release from the Red Wolf Recovery Program and the U.S. Fish & Wildlife Service

More photos of the Jackson Zoo pups can be viewed here.

2013 Foster Pup

Pup season is winding down now here at the Red Wolf Recovery Program. Totals for 2013 will be announced shortly, but in the meantime, we thought we’d share a foster opportunity we had last week.  A female red wolf pup was born in late April this year at the Sandy Ridge captive site, the Red Wolf Species Survival Plan facility on Alligator River National Wildlife Refuge.  She was the sole survivor of her litter.  This presented a good opportunity to foster her into a wild litter of similar age.  Fostering pups from a captive litter to a wild litter has been a successful tool used by the Red Wolf Recovery Program as a means to increase the numbers of wild red wolves and enhance the genetic diversity of the wild population. 

Pup fostering was first used in 2002, when two captive-born pups were successfully fostered into a wild litter.  Since then, we have seen some success with pup fostering with similar efforts.  In fact, no wild red wolf mother has ever been known to reject a fostered pup, and the fostered pups’ survival rates appear to be equal to that of their wild-born packmates.  There are several factors that can determine the likelihood of successful fostering. Ideally, the pups need to be no older than two-weeks of age at the time of the fostering.  During this time, the strong maternal instinct of the mother decreases the likelihood of pup rejection. The pups have limited mobility at this age as well, which ensures they will stay in or nearby the den site (and the mother).  We also aim to have all the pups similar in age, which can reduce any one-sided competition for food.  Lastly, a potential foster mother is usually selected based on her having a relatively low number of pups in her litter. 

 Female pup in transport. Photo credit: USFWS/B. Bartel

Pup processing: collecting blood and inserting the transponder.
Photo credits: USFWS/B. Bartel

In this case, there were two female pups already present in the wild litter, and all the pups were between 9-11 days old.  Once the new foster pup was covered with the scent (urine) of the other pups in the litter, all three pups were placed back into the den. We’ll keep you posted on their progress!

  The new pack! Photo credit: USFWS/B. Bartel

To learn more, you can check out previous blogs on pup processing techniques or previous fostering efforts.