Goat Friendly Pastures
Twenty four dry pregnant does were randomly allocated to 6 grazing paddocks. Four goats were placed into each grazing unit. The paddocks were arranged into 3 blocks with each block having two paddocks, one grazed rotationally (move at 7 day intervals) and the latter was continuously grazed. The does grazed a sorghum sudangrass hybrid for 70 days during peak gastro-intestinal parasite infection conditions (July 7 –September 17). Does were not dewormed or supplemented by concentrate during the 70 days. Mineral was supplied to each animal free choice. All does in the study gained weight and were in acceptable body condition. Likewise, all does were only moderately anemic after 70 days without deworming. However, the non-rotated group consumed the succulent regrowth of the SSH and did not allow sufficient regrowth to occur. On the other hand, rotationally grazed paddocks showed exceptional growth potential for the sorghum sudangrass hybrid.
The objective of “Goat Friendly Pastures” demonstration is to increase producer, and related professional’s knowledge of the nutritional value of forages in the growth and development of the meat goat females and furthermore to use annual forages as a strategic element in the management of gastro-internal parasites. Secondly, this work should perhaps validate and quantify excepted antidotal information that states that pasture management techniques are effective tools for moderation of gastro-intestinal parasite infections in goats.
One of the three farms selected as experimental farms began an experiment in early July of 2003. Extreme wet and cold conditions slowed the initial start of all three projects. As a result, two starts were delayed to the spring of 2004 while a second year of data will be collected from the initial start. The study began in Pulaski County Kentucky by grazing 24-dry pregnant does on a sorghum sudangrass, brown mid-rib hybrid, (SSH). The SSH was seeded June 21 into an establish KY 31, tall fescue field by means of a no-till drill. The seeding rate was 120 lbs of SSH/acre plus 50 lbs of N/a at seeding and again in 60 days. No additional tillage or chemicals were used to control grass growth following the drill operation.
Twenty four dry pregnant does were randomly allocated to 6 grazing paddocks. Four goats were placed into each grazing unit. The paddocks were arranged into 3 blocks with each block having two paddocks, one grazed rotationally (move at 7 day intervals) and the latter was continuously grazed. Paddock subdivisions were set on fixed areas of 3600 ft2 (x 5) while the set stock group grazed paddocks measuring 18,000 ft2 thus allowing each group equal access to grazing areas. The daily forage alliance for goats in rotation was approximately 5% of body weight in dry matter (DM). Furthermore, the overall stocking rate was 9.6 hd/a and for goats in rotation, the stock density was 48.2 hd/a. Note: Recommended stocking rates for permanent grass based pastures in Kentucky is 3 adult goats/a. Prior to placing does on paddocks each doe was processed for live body weight (LBW), body condition scored (BCS), color of the mucus membrane (CMM) was recorded, (goats were de-wormed 2 days prior to going on pasture) and fecal egg counts (FEC) were determined. FECs were determined from fecal samples taken from each doe in the study. Determination of each parameter was repeated on day 30 and 70. Does were placed on pasture July 7 and removed on September 17, 2003.
Impacts and Contributions/Outcomes
Five preliminary conclusions can be made from the experiences obtain in the 2003 study. First, SSH is a suitable feed for dry pregnant does in early to mid-gestation. Both the non-rotated and rotated groups gained 28.06 and 23.33 lbs of LBW respectively. The non-rotated group increased BCS from 2.83 to 2.91 (on a 1-5 scale) in 70 days while the rotated group lost body condition. The initial score for the rotated group was 2.5 and increasing to 2.71 in 30 days and dropped to 2.33 in 70 days. However both groups remained in adequate body condition throughout the 70 day study period without supplemental feeding.
Next, SSH is a highly productive warm season annual that integrates well with cool season perennial forages. SSH can be seeded in late May, while goats graze high quality cool season perennial pastures. Grazing cool season pastures can start as early as April 15 and should end in early summer (July 1). The second step is to move animals off parasite egg infested perennial pastures and begin grazing warm season annuals such as SSH. Goats graze above parasite on the up right growing annuals while the sunlight, high temperatures and drying conditions reduce egg counts on the perennial pastures. Third, SSH is conducive to higher stocking rates. This 70 day study supported a 2/3 increase in stocking rate for both the non-rotated and the rotated group. Fourth, SSH has a rapid regrowth potential. Following rotational grazing of SSH, DM regrowth for weeks one through three was 275 lbs, 1763 lbs and 2716 lbs per acre respectively.
CMM remained acceptable throughout the 70 day study. On a scale of 1-3, with 1=pink (no anemia) 2=moderately pink (slight anemia) and 3=pale (anemia) all goats in the study remained in the 1 and 2 condition without deworming. FECs were near 0 eggs/g of feces following the initial deworming and increase to 173.09 (non-rotated) and 206.80 (rotated) at the end of the 70 day period. These numbers indicate a need for treatment but are well below life treating levels. FECs for goats grazing at high stocking rates during summer months would commonly be at 500 eggs/g and could be as high as 1500 eggs/g (Dr. Gil Myers PhD, consulting parasitologest, Buffalo KY. ). All test-does kidded with in one to two months of the close of the 2003 study year. No adverse effects were observed due to treatment. The average kidding rate for all 24 females was 200%. All does appeared to lactate sufficient enough to maintain 2 kids.
Observations made during the 70 day study were if grazing is not managed through rotation, goats will continuously consume emerging succulent regrowth and drastically reduce the carrying capacity. Secondly, if grazing goats are not controlled, they will socialize at one location in the field (usually at the starting point of grazing) and this may increase parasite infection. Finally, goats grazing in rotation may become infected with internal parasites when DM becomes limiting. Without the opportunity for goats to grazing above the infection zone (a zone usually 2 to 4 inches above the soil line) they will graze low to the ground. SSH may increase parasite Laval survival rates and increase infection height on the low growing grasses due to the microclimate created by the dense SSH canopy.
Preliminary recommendations ascertained from the 2003 grazing year are to set daily forage alliance at 8-10% of LBW. Secondly, keep foliage residue levels at 25% of the total plant height. Set paddock residence time at 7 to 10 days with a return to graze time of 14 to 21 days. A minimum of 4 paddocks are need but may not be utilized throughout the grazing season. Therefore, grazing companions (steers, cows, horses) or hay making is essential in controlling excess growth. Finally, based on this years DM yields 1/3 acre of SSH is need for each acre of permanent cool season pasture (based on 3 does/acre).