2014 Pen vs. Pasture Study
2014 was the third and final year of the pen vs. pasture study at the University of Maryland's Western Maryland Research & Education Center. Thirty Kiko bucks were obtained from a farm in New Jersey. They were randomly allocated to two treatment groups: PEN vs. PASTURE.
As shown in the table below, the two groups were very similar in terms of their starting weights, fecal egg counts, and other traits. Upon arrival, the goats were sequentially dosed with anthelmintics from each anthelmintic class: albendazole (Valbazen® @ 2 ml/11 lbs), moxidectin (Cydectin® @ 2 ml/11 lbs.) and levamisole (Prohibit® @ 3 ml/50 lbs). For the first five days of the test, sulfadimethoxine (Di-methox®) was added to the drinking water (2 oz/25 gal), as a treatment for coccidiosis.
After a short 6-day adjustment period, the bucks consumed their respective diets for 84 days. The PEN goats (n=15) were fed hay and grain. A good quality mixed hay was limit-fed in two 4-foot hay racks with vertical slats. Whole barley was gradually introduced to the diet of the PEN goats. It was increased according to appetite and averaged 1 lb. per head per day over the duration of the study. The grain was fed in 4-foot poly troughs that were hung on the side of the fence and removed after feeding. Free choice minerals were offered.
The PASTURE goats (n=15) grazed along side the goats (TEST, n=77) in the Western Maryland Pasture-Based Meat Goat Performance Test. They were rotationally grazed among six, 2-2 1/2 acre paddocks. For the first half of the study, the PASTURE goats grazed cool season grass paddocks that had been precontaminated by sheep. During the second half of the feeding period, the PASTURE goats grazed warm season annual grasses and legumes: dwarf pearl millet, cow peas, and Sunn Hemp. Mid-way through the feeding period, the PASTURE goats were supplemented with soybean hulls, at a rate of 1.5% of body weight or approximately 0.75 lbs. per head per day.
All of the bucks in the study and test were handled bi-weekly to determine body weights, FAMACHA© scores, body condition scores, coat condition scores, dag scores, and fecal consistency scores. Individual fecal samples were collected bi-weekly to determine fecal egg counts. Pooled fecal samples were collected every 28 days for fecal coproculture (larvae ID). Six fecal samples were collected to determine the quality of the diet the goats were consuming.
Results
The PEN goats had significantly higher rates-of-gain than the PASTURE goats: 0.211 + 0.075 lb/d vs. 0.075 + 0.056 lb/d. The PEN goats had a higher rate-of-gain in all weigh periods except for the last two weeks, when the PASTURE goats gained more. 0.261 + 0.216 vs. 0.017 + 0.190 lb/d. At the end of the study, the PEN goats were significantly heavier than the PASTURE goats: 70.7 + 11.4 vs. 55.5 + 9.1 lbs.
The PEN goats had significantly lower fecal egg counts throughout the study, though the egg counts of the pen goats were higher than expected.
The PEN goats had lower FAMACHA© scores throughout the study. None of the PEN goats required deworming. While the PASTURE goats had significantly higher fecal egg counts, only five anthelmintic treatments were administered to the PASTURE goats. On the final day of the study, one of the PASTURE goats had a FAMACHA© score of 5. It was dewormed and removed from the carcass portion of the study.
Carcass data
On August 296, all of the study bucks were transported to Country Foods, a custom-exempt abattoir in Waynesboro (PA), for same day slaughter. Prior to slaughter, the two group of goats were mixed and they were fed hay to minimize fighting. This resulted in lower-than-expected carcass weights and dressing percentages. Dressing percentage is affected by many factors, including gut fill.
The chilled carcasses were deboned and measured four days later. A sample of the longissimus dorsi was removed from each carcass and is being analyzed for fatty acid content. As compared to the PASTURE goats, the PEN goats had heavier starting and ending weights, hot carcass weights (HCW), and cold carcass weights (CCW).
Dressing percentages were determined by dividing hot carcass weights by live weights. The PEN goats had higher dressing percentages than the PASTURE goats: 40.9 + 2.5 percent vs. 38.5 + 1.9 percent. All of the carcass were deboned and separated into lean, bone, and fat portions. Kidney and heart fat (KH) was weighed separately and determined as a carcass percentage. Carcass percentages of fat, bone, and lean were determined. Yield was calculated by dividing the lean weight by live weight.
The PEN goats had a higher percentage of carcass lean than the PASTURE goats: 57.1 + 2.6 vs. 54.1 + 1.9 percent. The PASTURE goats had a higher percentage of bone: 44.1 + 1.9 vs. 40.1 + 3.6 percent.
The carcasses from the PEN goats contained a higher percentage of kidney and heart fat (2.90 + 0.86 vs. 1.70 + 0.80 percent) and overall fat (3.51 + 1.12 vs. 2.04 + 0.83 percent). At the same time, none of the carcasses contained excessive fat. The carcasses from the PASTURE goats were especially lean, with very little trimmable fat.
The PEN goats yielded more boneless lean (10.49 + 1.72 vs. 8.90 + 1.02 lbs) than the PASTURE goats. Their yield was also higher: 21.3 + 2.3 vs. 18.9 + 1.5 percent.
Rib eye area was measured using a plastic grid (20 dots=1 square inch). The PEN goats had larger rib eye areas than the PASTURE goats: 1.44 + 0.31 vs. 1.11 + 0.13 square inches.
Compared to the PASTURE goats, the PEN goats had higher leg circumference: 29.3 + 2.3 vs. 26.9 + 1.4 centimeters.
While pen feeding improved the health, performance, and carcass charactersistics of meat goats in this study, the economics of pen feeding will vary by farm and year. Feed costs and market prices will factor heavily into the profitability calculation. The internal parasite challenge will also have a large bearing on profitability. If parasites are not adequately controlled, significant death losses can occur on pasture. In the very least, gain will be affected.
For the third consecutive year, the 2014 Pen vs. Pasture Study was funded by the Maryland Grain Producers Utilization Board.
