TY - JOUR
T1 - Effects of nutritional restriction on metabolic, endocrine, and ovarian function in llamas (Lama glama)
AU - Norambuena, M. C.
AU - Silva, M.
AU - Urra, F.
AU - Ulloa-Leal, C.
AU - Fernández, A.
AU - Adams, G. P.
AU - Huanca, W.
AU - Ratto, M. H.
N1 - Funding Information:
This study was supported by: Fondecyt/Postdoctorado grant no 3110095 (C Norambuena) and Biotecnologías Reproductivas en Alpacas y Llamas , INCAGRO , PROCYT , UNMSM , Lima, Peru (W. Huanca). We thank Dr. Sergio Recabarren, Dr. Albert Carrasco, Dr. Felipe Diaz for your valuable technical support with hormone analysis and Mr. Ruben Nempu for their valuable assistant in the management of the animals.
PY - 2013/5
Y1 - 2013/5
N2 - The objectives of the study were to determine the effects of nutritional restriction on ovarian function in llamas. Mature female llamas were assigned randomly to a Control group, fed 100% of maintenance energy requirements (MER) (n=8), or a Restricted group (n=8) fed from 70% to 40% of MER until a body condition score of 2.5 was attained. Blood samples were taken every-other-day to determine plasma concentrations of LH, estradiol, leptin and metabolic markers, and follicular dynamics were monitored daily by ultrasonography for 30 days (Experiment 1). Llamas were then treated with GnRH to compare the ovulatory response and corpus luteus (CL) development between groups (Experiment 2). Blood samples were taken to measure LH, leptin, progesterone and metabolic markers and ovarian structures were assessed as in Experiment 1. Llamas in the Restricted group had lower body mass and body condition scores than those in the Control group (P<0.001). Plasma concentrations of cholesterol, non-esterified fatty acids, triglycerides, and urea were higher in the Restricted group (P<0.05) than in the Control group. The day-to-day diameter profiles of the dominant follicles were smaller (P<0.05) in the Restricted group than in the Control group but plasma estradiol concentration did not differ. The ovulation rate and LH secretion in response to GnRH did not differ. Day-to-day profiles of CL diameter, plasma progesterone and leptin concentrations were smaller (P<0.01) in the Restricted group. In conclusion, nutritional restriction in llamas was associated with suppressed follicle and CL development, and lower plasma concentrations of progesterone and leptin.
AB - The objectives of the study were to determine the effects of nutritional restriction on ovarian function in llamas. Mature female llamas were assigned randomly to a Control group, fed 100% of maintenance energy requirements (MER) (n=8), or a Restricted group (n=8) fed from 70% to 40% of MER until a body condition score of 2.5 was attained. Blood samples were taken every-other-day to determine plasma concentrations of LH, estradiol, leptin and metabolic markers, and follicular dynamics were monitored daily by ultrasonography for 30 days (Experiment 1). Llamas were then treated with GnRH to compare the ovulatory response and corpus luteus (CL) development between groups (Experiment 2). Blood samples were taken to measure LH, leptin, progesterone and metabolic markers and ovarian structures were assessed as in Experiment 1. Llamas in the Restricted group had lower body mass and body condition scores than those in the Control group (P<0.001). Plasma concentrations of cholesterol, non-esterified fatty acids, triglycerides, and urea were higher in the Restricted group (P<0.05) than in the Control group. The day-to-day diameter profiles of the dominant follicles were smaller (P<0.05) in the Restricted group than in the Control group but plasma estradiol concentration did not differ. The ovulation rate and LH secretion in response to GnRH did not differ. Day-to-day profiles of CL diameter, plasma progesterone and leptin concentrations were smaller (P<0.01) in the Restricted group. In conclusion, nutritional restriction in llamas was associated with suppressed follicle and CL development, and lower plasma concentrations of progesterone and leptin.
KW - Camelids
KW - Corpus luteum
KW - LH
KW - Leptin
KW - Nutritional restriction
UR - http://www.scopus.com/inward/record.url?scp=84876838013&partnerID=8YFLogxK
U2 - 10.1016/j.anireprosci.2013.01.019
DO - 10.1016/j.anireprosci.2013.01.019
M3 - Artículo
C2 - 23562451
AN - SCOPUS:84876838013
SN - 0378-4320
VL - 138
SP - 252
EP - 260
JO - Animal Reproduction Science
JF - Animal Reproduction Science
IS - 3-4
ER -