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| Acceso al texto completo restringido a Biblioteca INIA La Estanzuela. Por información adicional contacte bib_le@inia.org.uy. |
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Biblioteca (s) : |
INIA La Estanzuela. |
Fecha : |
02/10/2017 |
Actualizado : |
05/11/2019 |
Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
Autor : |
DAMIAN, J.P.; HÖTZEL, M.J.; BANCHERO, G.; UNGELFERD, R. |
Afiliación : |
JUAN PABLO DAMIAN, UdelaR (Universidad de la República), FVET ( Facultad de Veterinaria), Montevideo, Uruguay.; MARIA JOSÉ HÖTZEL, Laborat#1;orio de Etologia Aplicada e Bem-Estar Animal, Departamento de Zootecnia e Desenvolvimento Rural, Universidade Federal de Santa Catarina, Florian#1;opolis, Brazil.; GEORGGET ELIZABETH BANCHERO HUNZIKER, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; RODOLFO UNGELFERD, RODOLFO UNGERFELD, UdelaR (Universidad de la República), FVET ( Facultad de Veterinaria), Montevideo, Uruguay. |
Título : |
Competition for oestrous ewes between rams reared by their mothers or artificially reared: Effects on sexual behaviour and testosterone and cortisol serum concentrations. |
Fecha de publicación : |
2017 |
Fuente / Imprenta : |
Theriogenology, v.100, p. 134-138, 2017. |
DOI : |
doi.org/10.1016/j.theriogenology.2017.06.009 |
Idioma : |
Inglés |
Notas : |
Article history: Received 4 November 2016//Received in revised form 5 June 2017//Accepted 6 June 2017//Available online 8 June 2017. |
Contenido : |
A b s t r a c t:
The objective of this study was to determine how the social competition for an oestrous ewe affects the
sexual behaviour and the endocrine response in two groups of rams, one reared by their mothers and
another artificially reared. Thus, we compared the sexual behaviour and testosterone and cortisol
changes in each group of rams in competitive and non-competitive tests, both during the first and second
breeding seasons. Two groups of rams were: 1) artificially reared lambs, separated from their dams 24
e36 h after birth (Week 0) and artificially fed with sheep milk until 10 weeks of age (group AR, n ¼ 14);
and 2) lambs reared by their dams until 10 weeks of age (group DR, n ¼ 13). Rams were subjected to noncompetitive
and competitive tests for an oestrous ewe during their first and second breeding seasons,
when they were 8 and 20 months old, respectively. Sexual behaviours toward an oestrous ewe were
recorded during 20 min and the testosterone and cortisol concentrations were determined in serum
samples collected immediately before the test, and 20, 40 and 60 min after it. During the first breeding
season, the number of flehmen decreased in DR rams, and the number of flehmen and ano-genital
sniffings also decreased in DR rams, but the frequency of some copulatory behaviours increased (matings
and ejaculation/total mounts in DR rams, and total mounts in AR rams) in competitive tests. During
the second breeding season, competition caused a decrease in the number of all the recorded behaviours
(courtship and copulation) with the exception of flehmen in AR rams; however, in DR rams only the
number of the copulatory behaviours decreased under competition. Competition did not affect the
endocrine response during the first breeding season. During the second breeding season, while testosterone
concentrations were greater in non-competitive than in competitive tests at 60 min (P ¼ 0.0008)
in AR rams, in DR rams it tended to be greater (P ¼ 0.09). Competition did not affect cortisol concentrations
in any group or season, but in all tests the concentrations increased at the end of the test
(P < 0.05). In conclusion, the lack of the mother during rearing negatively affected the sexual motivation
and the testosterone response of rams to oestrous ewes in competitive tests, effects that were more
evident when adults. Neither the absence of the mother during rearing nor competition for oestrous
ewes affected the stress response (evidenced by increase in cortisol concentration) in rams during both
seasons. MenosA b s t r a c t:
The objective of this study was to determine how the social competition for an oestrous ewe affects the
sexual behaviour and the endocrine response in two groups of rams, one reared by their mothers and
another artificially reared. Thus, we compared the sexual behaviour and testosterone and cortisol
changes in each group of rams in competitive and non-competitive tests, both during the first and second
breeding seasons. Two groups of rams were: 1) artificially reared lambs, separated from their dams 24
e36 h after birth (Week 0) and artificially fed with sheep milk until 10 weeks of age (group AR, n ¼ 14);
and 2) lambs reared by their dams until 10 weeks of age (group DR, n ¼ 13). Rams were subjected to noncompetitive
and competitive tests for an oestrous ewe during their first and second breeding seasons,
when they were 8 and 20 months old, respectively. Sexual behaviours toward an oestrous ewe were
recorded during 20 min and the testosterone and cortisol concentrations were determined in serum
samples collected immediately before the test, and 20, 40 and 60 min after it. During the first breeding
season, the number of flehmen decreased in DR rams, and the number of flehmen and ano-genital
sniffings also decreased in DR rams, but the frequency of some copulatory behaviours increased (matings
and ejaculation/total mounts in DR rams, and total mounts in AR rams) in competitive tests. During
the second breeding season, competition caused a decrease in the numb... Presentar Todo |
Palabras claves : |
CORTISOL; MOTHER-OFFSPRING; SHEEP; STRESS; TESTOSTERONE. |
Thesagro : |
OVEJA. |
Asunto categoría : |
-- |
Marc : |
LEADER 03469naa a2200253 a 4500 001 1057622 005 2019-11-05 008 2017 bl uuuu u00u1 u #d 024 7 $adoi.org/10.1016/j.theriogenology.2017.06.009$2DOI 100 1 $aDAMIAN, J.P. 245 $aCompetition for oestrous ewes between rams reared by their mothers or artificially reared$bEffects on sexual behaviour and testosterone and cortisol serum concentrations.$h[electronic resource] 260 $c2017 500 $aArticle history: Received 4 November 2016//Received in revised form 5 June 2017//Accepted 6 June 2017//Available online 8 June 2017. 520 $aA b s t r a c t: The objective of this study was to determine how the social competition for an oestrous ewe affects the sexual behaviour and the endocrine response in two groups of rams, one reared by their mothers and another artificially reared. Thus, we compared the sexual behaviour and testosterone and cortisol changes in each group of rams in competitive and non-competitive tests, both during the first and second breeding seasons. Two groups of rams were: 1) artificially reared lambs, separated from their dams 24 e36 h after birth (Week 0) and artificially fed with sheep milk until 10 weeks of age (group AR, n ¼ 14); and 2) lambs reared by their dams until 10 weeks of age (group DR, n ¼ 13). Rams were subjected to noncompetitive and competitive tests for an oestrous ewe during their first and second breeding seasons, when they were 8 and 20 months old, respectively. Sexual behaviours toward an oestrous ewe were recorded during 20 min and the testosterone and cortisol concentrations were determined in serum samples collected immediately before the test, and 20, 40 and 60 min after it. During the first breeding season, the number of flehmen decreased in DR rams, and the number of flehmen and ano-genital sniffings also decreased in DR rams, but the frequency of some copulatory behaviours increased (matings and ejaculation/total mounts in DR rams, and total mounts in AR rams) in competitive tests. During the second breeding season, competition caused a decrease in the number of all the recorded behaviours (courtship and copulation) with the exception of flehmen in AR rams; however, in DR rams only the number of the copulatory behaviours decreased under competition. Competition did not affect the endocrine response during the first breeding season. During the second breeding season, while testosterone concentrations were greater in non-competitive than in competitive tests at 60 min (P ¼ 0.0008) in AR rams, in DR rams it tended to be greater (P ¼ 0.09). Competition did not affect cortisol concentrations in any group or season, but in all tests the concentrations increased at the end of the test (P < 0.05). In conclusion, the lack of the mother during rearing negatively affected the sexual motivation and the testosterone response of rams to oestrous ewes in competitive tests, effects that were more evident when adults. Neither the absence of the mother during rearing nor competition for oestrous ewes affected the stress response (evidenced by increase in cortisol concentration) in rams during both seasons. 650 $aOVEJA 653 $aCORTISOL 653 $aMOTHER-OFFSPRING 653 $aSHEEP 653 $aSTRESS 653 $aTESTOSTERONE 700 1 $aHÖTZEL, M.J. 700 1 $aBANCHERO, G. 700 1 $aUNGELFERD, R. 773 $tTheriogenology$gv.100, p. 134-138, 2017.
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| Acceso al texto completo restringido a Biblioteca INIA Tacuarembó. Por información adicional contacte bibliotb@tb.inia.org.uy. |
Registro completo
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Biblioteca (s) : |
INIA Tacuarembó. |
Fecha actual : |
14/04/2015 |
Actualizado : |
25/11/2019 |
Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
Circulación / Nivel : |
Internacional - -- |
Autor : |
WILMAN, D.; OLMOS, F.; HAMILTON, R.S. |
Afiliación : |
D. WILMAN, Institute of Rural Sciences, University of Wales, Aberystwyth SY23 3AL, UK; FERNANDO ELCEAR OLMOS LOPEZ, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; R. S. HAMILTON, Institute of Grassland and Environmental Research, Aberystwyth SY23 3EB, UK. |
Título : |
The potential of seed-shedding and seedling development to contribute to the persistence of white clover (Trifolium repens) in grazed swards in Uruguay. |
Fecha de publicación : |
2005 |
Fuente / Imprenta : |
Journal of Agricultural Science, 2005, v143, 493-501. |
DOI : |
10.1017/S0021859605005654 |
Idioma : |
Inglés |
Notas : |
Article history: Revised MS received 19 August 2005. |
Contenido : |
The present study was conducted to investigate whether white clover (Trifolium repens L.) in grazed swards in Uruguay can produce and shed sufficient seed, and whether sufficient seedlings can develop and survive, to make an important contribution to the long-term persistence of the species. Five sites, on which survival of white clover had been better than is usual in Uruguay, were studied in 1995–97. The sites had been sown with white clover 11–15 years previously and were managed mainly by cattle grazing. The number of white clover inflorescences/m2 was at least 18 at nearly half the counts in the study and the number of viable seeds in the top 5 cm of soil was at least 1500 at half the counts. The results for both the above variables suggest that all five sites had a supply of seed greater than a commercial seed rate at some times of the year. However, the number of seedlings/m2 was >100, a possible target in these conditions, at only one fifth of the counts, and the proportion of seedlings that
survived from one recording date to the next (a period of 4–5 weeks) varied from >0.7 to zero. It seems, therefore, that, in these conditions, the failure of seeds to convert to established plants is likely to be a greater constraint than the production and shedding of seeds. There was considerable variability with time, and between and within sites at each stage of the reproductive cycle. On one site, competition from Bermudagrass (Cynodon dactylon) greatly reduced the number of white clover
seedlings/m2. Overall, the results suggest that white clover in grazed swards in Uruguay can produce and shed sufficient seed, and that sufficient seedlings can develop and survive, to make a significant contribution to the long-term persistence of the species. However, each year there is a risk of seedlings being killed in dry, hot weather. MenosThe present study was conducted to investigate whether white clover (Trifolium repens L.) in grazed swards in Uruguay can produce and shed sufficient seed, and whether sufficient seedlings can develop and survive, to make an important contribution to the long-term persistence of the species. Five sites, on which survival of white clover had been better than is usual in Uruguay, were studied in 1995–97. The sites had been sown with white clover 11–15 years previously and were managed mainly by cattle grazing. The number of white clover inflorescences/m2 was at least 18 at nearly half the counts in the study and the number of viable seeds in the top 5 cm of soil was at least 1500 at half the counts. The results for both the above variables suggest that all five sites had a supply of seed greater than a commercial seed rate at some times of the year. However, the number of seedlings/m2 was >100, a possible target in these conditions, at only one fifth of the counts, and the proportion of seedlings that
survived from one recording date to the next (a period of 4–5 weeks) varied from >0.7 to zero. It seems, therefore, that, in these conditions, the failure of seeds to convert to established plants is likely to be a greater constraint than the production and shedding of seeds. There was considerable variability with time, and between and within sites at each stage of the reproductive cycle. On one site, competition from Bermudagrass (Cynodon dactylon) greatly reduced the number of... Presentar Todo |
Thesagro : |
TRIFOLIUM REPENS; URUGUAY. |
Asunto categoría : |
A50 Investigación agraria |
Marc : |
LEADER 02518naa a2200193 a 4500 001 1052520 005 2019-11-25 008 2005 bl uuuu u00u1 u #d 024 7 $a10.1017/S0021859605005654$2DOI 100 1 $aWILMAN, D. 245 $aThe potential of seed-shedding and seedling development to contribute to the persistence of white clover (Trifolium repens) in grazed swards in Uruguay. 260 $c2005 500 $aArticle history: Revised MS received 19 August 2005. 520 $aThe present study was conducted to investigate whether white clover (Trifolium repens L.) in grazed swards in Uruguay can produce and shed sufficient seed, and whether sufficient seedlings can develop and survive, to make an important contribution to the long-term persistence of the species. Five sites, on which survival of white clover had been better than is usual in Uruguay, were studied in 1995–97. The sites had been sown with white clover 11–15 years previously and were managed mainly by cattle grazing. The number of white clover inflorescences/m2 was at least 18 at nearly half the counts in the study and the number of viable seeds in the top 5 cm of soil was at least 1500 at half the counts. The results for both the above variables suggest that all five sites had a supply of seed greater than a commercial seed rate at some times of the year. However, the number of seedlings/m2 was >100, a possible target in these conditions, at only one fifth of the counts, and the proportion of seedlings that survived from one recording date to the next (a period of 4–5 weeks) varied from >0.7 to zero. It seems, therefore, that, in these conditions, the failure of seeds to convert to established plants is likely to be a greater constraint than the production and shedding of seeds. There was considerable variability with time, and between and within sites at each stage of the reproductive cycle. On one site, competition from Bermudagrass (Cynodon dactylon) greatly reduced the number of white clover seedlings/m2. Overall, the results suggest that white clover in grazed swards in Uruguay can produce and shed sufficient seed, and that sufficient seedlings can develop and survive, to make a significant contribution to the long-term persistence of the species. However, each year there is a risk of seedlings being killed in dry, hot weather. 650 $aTRIFOLIUM REPENS 650 $aURUGUAY 700 1 $aOLMOS, F. 700 1 $aHAMILTON, R.S. 773 $tJournal of Agricultural Science, 2005, v143, 493-501.
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