Final Data

The lambs were weighed for a final time on September 25. This was 91 days after they were split into their two treatment groups. For this final weigh period (of 11 days), the PASTURE group (n=36) had a much higher ADG than the SUPPLEMENTED group (n=37):  0.555 ± 0.305 vs. 0.188 ± 260 lbs. per day. They had a 0.4 unit advantage in FAMACHA© scores: 1.6 vs. 2.0. Two of the SUPPLEMENTED lambs were dewormed, with one having a FAMACHA© score of 4. 

However, for the 91-day duration of the study, the SUPPLEMENTED lambs had a higher ADG (+9.3%) than the PASTURE lambs:  0.386 ± 0.059 vs. 0.353 ± 0.059 lbs. per day. The SUPPLEMENTED lambs had heavier final ending weights than the PASTURE lambs: 108.6 ± 15.5 vs. 106.6 ± 13.9 lbs. They finished the study with a 0.2 unit advantage in body condition score. Throughout the study, the PASTURE lambs tended to have higher dag scores (more scours).

For the 73 lambs that finished the study, ADG ranged from 0.209 to 0.543 lbs. per day and averaged 0.370 ± 0.061 lbs. per day. No lamb lost weight. However, four lambs were removed from the PASTURE group and two lambs were removed from the SUPPLEMENTED group.

Day 80

Lambs were weighed on September 14. FAMACHA©, body condition, and dag scores were determined. Over the past two weeks, ADG ranged from -0.471 to 0.843 lbs. per day and averaged 0.348 ± 0.243 lbs. per day. The median ADG was 0.371 lbs. per day. The supplemented lambs (n=37) had a higher ADG than the (non-supplemented) pasture-only (n=36) lambs: 0.425 ± 0.209 vs. 0.263 ± 0.251 lbs. per day. 

The supplemented lambs receive 1 lb. of whole barley per day. Both groups are rotated to new pastures every 7 days. Each group has 5 acres of pasture divided into four equal sized paddocks. Forage samples are collected weekly on the day the lambs begin grazing the new paddock. While it was dry in July, pasture quality and quantity has been high throughout the study.

September 14th marked the 80th day of the study. The study started on June 26 after the lambs grazed a silvopasture during an 11 day acclimation period. Among all the lambs in the study, ADG has ranged from 0.190 to 0.560 lbs per day and averaged 0.378 ±  0.074 lbs. per day. While no lamb has lost weight, six lambs have been removed from the study. The supplemented lambs have a higher ADG than the pasture-only lambs: 0.418 ± 0.064 vs. 0.339 ± 0.063 lbs. per day.

On September 14, FAMACHA© scores ranged from 1 to 4. A FAMACHA© score of 4 was observed for the first time. This lamb was dewormed, along with several other lambs with FAMACHA© scores of 3. Deworming decisions are based on the criteria of the Five Point Check©. FAMACHA© 3's that lose weight are also dewormed. 

More lambs in the pasture-only group had positive dag scores and looser stools. Lambs with positive dag scores and evidence of loose manure were given probiotics. The looseness of the stools is attributed to the high moisture content of the pastures. The supplemented lambs have a 0.4 unit advantage in body condition score compared to the non-supplemented lambs.

Due to Covid 19, we are unable to have the lambs processed to collect actual carcass data. Instead the lambs will be scanned on September 25 for backfat and loin depth. The lambs will be weighed a final time to get ending weights for the study.