Jean-Marie Luginbuhl

Use of goats as biological agents for the renovation of pastures in the Appalachian region of the United States.

Much of hill-land pasture in the Appalachian region of the United States is dominated by herbaceous weeds and brush. Low cost, low input and environmentally acceptable reclamation procedures are needed to maintain the productivity of these pastures. This experiment evaluated the effectiveness of using goats (Capra hircus hircus) alone (30 mature, brush does/ha) or cattle (Bos taurus) with goats (17 mature, brush does/ha + two to three steers/ha -- 225 kg average live weight) to reclaim a pasture from an abandoned, overgrown 5.9 ha orchard left untouched for 15 years. Over four grazing seasons, managed defoliation resulted in a substantial increase in herbaceous vegetative cover in plots grazed by goats alone (65 to 86%) and by goats with cattle (65 to 80%) while vegetative cover decreased from 70 to 22% in the control plot. Similarly, the cover by grass species increased in the grazed plots (goats: 16 to 63%; goats + cattle: 13 to 54%) while averaging 10% in the control plot. Multiflora rose (Rosa multiflora Thumb.) bushes were practically eliminated after four grazing seasons as quantified by an average reduction in height from 2.1 m to 0.6 m, and by the number of dead canes (stems) in both the goat (100%) or goat + cattle (92%) treatments. Results indicated that the foraging habits of goats resulted in the elimination of multiflora rose bushes and in a significant increase in desirable forage species.

Dietary Chemical Composition, Plasma Metabolites and Hormones in Range Goats

Abstract Juárez-Reyes, A.S., Nevarez-Carrasco, G., Cerrillo-Soto, M.A., Murillo-Ortiz, M., Luginbuhl, J-M., Bernal-Barragán, H. and Ramírez, R.G. 2008. Dietary chemical composition, plasma metabolites and hormones in range goats. J. Appl. Anim. Res, 34: 81–86. The objective of this study was to determine the monthly chemical composition of the diet consumed by range goats and plasma concentrations of glucose, urea, non-esterified fatty acids (NEFA), luteinizing hormone (LH), growth hormone (GH), insulin and progesterone (P4) during lactation (January-June). Three esophageally-cannulated female goats and twelve intact female goats (38±1.7 kg BW) were used to obtain extrusa and blood samples, respectively. Body weight decreased (P<0.05) by 12.5% during the period from January to May, whereas, in June goats lost 250 g d−1. There was a fall in nutrient density during May and June. With the exception of progesterone (0.1–0.6 ng ml−1), LH (7.1–11.0), GH (22.8–30) and insulin (0.6–1.8) increased (P<0.05) as lactation period progressed. It is concluded that plasma metabolite concentrations suggested that an energy supplementation schedule might be necessary during the early lactation period of goats. In addition, if harsh climatic conditions appear at the end of lactation, an increment of 70% in their energy maintenance requirements might be considered to avoid weight losses and to improve body condition of goats prior to breeding season.

Establishment and early growth characteristics of six Paulownia genotypes for goat browse in Raleigh, NC, USA

Meat goat production in the eastern USA is increasing as a result of growing demand from various ethnic groups. Because goats naturally prefer a high proportion of browse in their diets, research was initiated to investigate various silvopastoral production systems. The genus Paulownia contains several species which exhibit rapid juvenile growth and other characteristics that justify research into their potential use in meat goat feeding systems. In May 1997, six Paulownia genotypes were planted in a randomized complete block experiment with six replications. Trees were between 6 and 12 cm in height at planting. Genotypes included: P. fortunei seedlings, P. tomentosa seedlings, P. elongata seedlings and three P. elongata clones. Each 4-m wide plot contained a single row of 12 trees with an intra-row spacing of 1 m. Plant measurements included height, root collar diameter (RCD) at 3 cm above soil surface, and the number of main branches. Leaf samples were collected from all six replications for estimates of herbage quality. During 1998, trees were browsed with goats on two occasions to assess palatability of the herbage and to determine any preference for specific genotypes by the animals. Compared with seedling trees of all three species, the three P. elongata clones were taller (clones: 79.7 cm, seedlings: 55.9 cm; P < 0.01), had larger RCDs (clones: 18.4 mm, seedlings: 13.9 mm; P < 0.01) and had a higher branching frequency (clones: 4.9, seedlings: 1.5; P < 0.01) by the end of the first growing season. Mortality averaged 4.8% across all treatments and ranged between 0 and 8%. Early in the 1998 growing season before trees were browsed, P. elongata clones grew more rapidly than seedlings (clones: 116.4 cm, seedlings: 84.1 cm; P < 0.01). Estimates of herbage quality indicated favorable concentrations of energy and protein for lamina. In vitro true dry matter disappearance ranged from 85.4 (blades) to 71.5% (petioles) and crude protein from 25.1 (blades) to 4.9% (petioles). Animals readily browsed the lamina during two separate sessions, but no clear preference trends were observed among the different Paulownia genotypes.