Effects of locoweed (Oxytropis sericea) on growth, reproduction, and serum hormone profiles in young rams


Por: Ortiz A.R., Hallford D.M., Galyean M.L., Schneider F.A., Kridli R.T.

Publicada: 1 ene 1997
Resumen:
Sixteen ram lambs (5 mo old, average BW = 49 ± 1.4 kg) received a control diet (50% concentrate, 13.1% CP) or a diet containing 7, 14, or 21% locoweed (LW, DM basis). Rams were housed in individual pens (2.5 × 3.5 m) in an enclosed facility (14 h light, 10 h dark) with free access to feed and water. After 35 d of LW feeding, rams fed the 21% LW diet ate 1.3 to 1.6 kg/d, whereas rams fed the other three diets ate 1.6 to 2.0 kg/d. On d 35, BW (mean ± SE) were 58.3, 57.2, 57.2, and 55.4 (± 1.5 kg/d) for ram lambs receiving 0, 7, 14, and 21% LW, respectively (P > .20). An inverse relationship for BW (P < .10) and gain (P = .04) was observed 1 mo after LW feeding ended relative to amount of LW in the diet. Serum alkaline phosphatase increased with increasing LW (P < .05), and thyroxine concentration was decreased (P < .05) by LW ingestion. On d 35, serum LH averaged 6.8, 9.9, 11.6, and 9.9 (± 1.8) ng/mL (P = .56), whereas testosterone averaged 3.5, 2.6, 3.0, and 1.6 (± .5) ng/mL (linear effect of LW, P = .05) over a 5-h period after GnRH injection (i.m., 50 ?g) in lambs fed 0, 7, 14, and 21% locoweed, respectively. Semen volume, sperm motility, sperm cell concentration, and percentage of abnormal cells did not differ (P > .50) on d 35. One month after the end of LW feeding, a linear (P = .06) decrease in sperm motility and scrotal circumference was observed relative to percentage of prior dietary LW. These data suggest that LW exerts adverse effects on the testes of young rams that may not be evident until several weeks after LW consumption ends.

Filiaciones:
Ortiz A.R.:
 Dept. of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, United States

Hallford D.M.:
 Dept. of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, United States

Galyean M.L.:
 Dept. of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, United States

 Div. of Agric., West Texas A and M Univ., Canyon, TX 79016, United States

Schneider F.A.:
 Dept. of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, United States

Kridli R.T.:
 Dept. of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, United States

 Jordan Univ. of Sci. and Tech., Irbid, Jordan
ISSN: 00218812
Editorial
AMER SOC ANIMAL SCIENCE, PO BOX 7410, CHAMPAIGN, IL 61826-7410 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 75 Número: 12
Páginas: 3229-3234
WOS Id: A1997YL46200018
ID de PubMed: 9419997

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