URBANA, Ill. – Parturition management is one of the most popular classes in the Department of Agriculture at Illinois State University.
“For this class, students are responsible for whelping animals at our Lexington research farm,” said Jennifer Earing, assistant professor in the ISU Department of Agriculture.
Three to four students sign up for six-hour shifts.
“It gives them a realistic perspective, and if they’re not comfortable with a situation, they can call the teaching assistant or the farm manager,” Earing said during a presentation at the day. sheep from Illinois lamb and wool producers.
About 400 students are enrolled in the ISU Department of Agriculture.
“We get a lot of students who want to go to vet school, but have minimal animal experience,” Earing said. “Most of our classes have a lab associated with them and sheep are the preferred species as they are not as intimidating as cattle.”
The ISU farm consists of approximately 100 head of Simmental/Angus cattle, 60 Dorset/Suffolk ewes and 100 sows.
Earing spoke of an on-farm research project that evaluated the ability to estimate fetal age using ultrasound in early gestation in ewes.
“The 2016 study showed 90% accuracy at day 31 and 100% accuracy at day 45,” she said.
ISU researchers conducted a second study with 15 Dorset ewes that were synchronized and exposed to a ram for a 24-hour period. The ewes were scanned by ultrasound starting on day 21 and then every other day until day 59.
“We recorded information on the number of fetuses and took video clips and made measurements from those clips which included the actual lambing date and the lamb’s body weight,” Earing said.
Eleven of the 15 ewes in the study were pregnant.
“For the fetal count, on day 21 the accuracy was 10% and there was a big jump from day 21 to day 26 to 60% accuracy,” Earing said. “Accuracy generally increased to a day 49 high of 90% accuracy.”
ISU graduate student Julissa Navarrete spoke about her research project that involved feeding sheep liquid brewer’s yeast, a by-product of the brewing industry.
“Little research has been done on lamb mortality,” Navarrete said.
“Research reports providing good nutrition to ewes is important for getting healthier lambs and another aspect of providing good nutrition is improving the quality or quantity of colostrum,” she said.
In addition, natural immunoglobulins are a factor that affects the survivability of lambs.
“Ewes have a placental barrier that prevents the passage of immunity, so lambs are born without immunity,” Navarrete said. “Ewes provide passive immunity through colostrum, so the first 48 hours are the most critical time for lambs to provide adequate colostrum.”
Therefore, Navarrete said, if colostrum is improved, it can increase the lamb’s survival rate.
“The objective of the study was to evaluate the by-product we were getting from a local distillery by feeding it to ewes to see if there was any improvement in colostrum quality or immunity for the offspring of the sheep,” she said.
The study included 14 ewes – seven in the control group who were fed a traditional late-gestation diet and seven who were fed 60 grams of dry matter per head per day of liquid brewer’s yeast mixed with grain.
“To measure passive immune transfer, we administered a parainfluenza vaccine to the ewes before starting the trial,” Navarrete said. “It’s not a very common vaccine for our sheep, so no antibodies would be present in ewes for this vaccine.”
Blood samples were taken to monitor immunity during gestation and after lambing.
“Before and after lambing, all the ewes were positive for the vaccine, so their immune systems were working,” Navarrete said. “And all the lambs were positive for the vaccine.”
Colostrum samples were taken from the ewes four hours after lambing and sent to a laboratory for analysis to determine fat and protein levels.
“We also ran the samples through a Brix refractometer,” Navarrete said. “Above 22% Brix is considered high quality colostrum, but we found no significant difference in the measurement of antibodies in the colostrum of the two groups of ewes.”
The conclusion of the study, Navarrete said, was that liquid brewer’s yeast did not improve or negatively affect immunity or colostrum quality.
“Further research needs to be done to determine how much liquid brewer’s yeast should be offered to see improvements,” she said.