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Author |
Bartosova, J.; Komarkova, M.; Dubcova, J.; Bartos, L.; Pluhacek J. |
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Title |
Nursing behaviour in pregnant domestic mares (Equus caballus): Can they cope with dual maternal investment? |
Type |
Conference Article |
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Year |
2012 |
Publication |
Proceedings of the 2. International Equine Science Meeting |
Abbreviated Journal |
Proc. 2. Int. Equine. Sci. Mtg |
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Volume |
in press |
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Keywords |
Suckling behaviour; pregnancy; parent-offspring conflict; domestic horses; Equus caballus |
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Abstract |
Among mammals, lactation is the most energy demanding part of parental care and so parentoffspring conflict should arise over milk provided by the mother. Mother and offspring should disagree over the length and amount of the milk provision. We focused on effect of pregnancy on suckling behaviour variables as indicators of mother-offspring conflict in domestic horses. We presumed shorter suckling bouts and higher rates of rejected and/or terminated suckling in pregnant mares compared to non-pregnant ones. Increasing conflict over amount of maternal investment between mother and her young are to be expected because of her parallel investment into a nursed foal and a foetus. Eight groups of loose housed lactating mares with foals of Kladruby horse were studied at the National Stud Kladruby nad Labem (Czech Republic) from deliveries to abrupt weaning (at the age of 127 to 210 days). We recorded 10 848 suckling solicitations of 79 mare-foal pairs, from which 10 607 resulted in a suckling bout. In 41 cases a nursing mare became pregnant during lactation. We found no significant effect of pregnancy either on probability of the mother rejecting suckling solicitation of her foal or probability that she terminated a suckling bout. However the overall effect of mother’s pregnancy on suckling bout duration was not significant, there were considerable differences in pregnant and non-pregnant mares according to who terminated a suckling bout, whether the mother or the foal (F(1, 9776) = 12.1, P < 0.001). In case it was the mother then the suckling bout was longer if she was pregnant (65.36 ± 1.25 s) than barren (60.55 ± 1.36 s). We found no impact of pregnancy on duration of suckling bouts terminated by the foal. Further, nursing a foal during the first two trimesters of pregnancy had no negative impact on birth weight of the foetus. In conclusion, we found not higher, but a lower mother-offspring conflict in pregnant than in non-pregnant lactating mares while expecting just the opposite. We suggest that pregnant mares compensate their nursed foals during intensive stages of lactation through a relaxed mother-offspring conflict for later decrease in investment due to increasing demands of the foetus and/or for the shorter period of milk supply. Our results (partly published in Bartosova et al. 2011, PLoS ONE 6(8): e22068) are of high importance in horse breeding. One of the main arguments for early weaning of the foals is regeneration of their pregnant mothers before upcoming delivery. Here we present evidence that a pregnant mare “counts” with her dual maternal investment and “employs” evolutionary mechanisms enabling her to rear a vital foetus. From this point of view there is no objective reason for stressful weaning of her nursed offspring practised in conventional breeding. Supported by AWIN, EU FP7 project No. 266213. |
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Corporate Author |
Bartosova, J. |
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Xenophon Publishing |
Place of Publication |
Wald |
Editor |
Krueger, K. |
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978-3-9808134-26 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
5501 |
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Author |
Kirkpatrick, J.F.; Turner, A. |
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Title |
Reversibility of action and safety during pregnancy of immunization against porcine zona pellucida in wild mares (Equus caballus) |
Type |
Journal Article |
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Year |
2002 |
Publication |
Reproduction (Cambridge, England) Supplement |
Abbreviated Journal |
Reprod Suppl |
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Volume |
60 |
Issue |
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Pages |
197-202 |
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Keywords |
Animals; *Animals, Wild; Antigens/administration & dosage; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; Fertility; *Horses; Immunization, Secondary/veterinary; Membrane Glycoproteins/administration & dosage; Population Control; Pregnancy; *Receptors, Cell Surface; Safety; Swine; Time Factors; Vaccines, Contraceptive/*administration & dosage |
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Abstract |
Contraceptive management of publicly valued wildlife species requires safeguards to ensure that these populations are preserved in a healthy state. In addition, reversibility of contraceptive effects and safety in pregnant animals are major concerns. A population of wild horses has been immunized against porcine zona pellucida (PZP) over a 12 year period on Assateague Island National Seashore, MD (ASIS). Mares initially received one or two 65 microg inoculations and once a year 65 microg booster inoculations, all delivered by dart. All young mares aged > 2 years were treated with PZP for 3 consecutive years regardless of whether they have bred successfully and they were then removed from treatment until they had foaled. All mares vaccinated for 1 or 2 consecutive years became fertile again and 69% of mares treated for 3 consecutive years returned to fertility. All five mares treated for 4 or 5 consecutive years have also returned to fertility, but over longer periods of time. Mares treated for 7 consecutive years have not returned to fertility, but several, while still infertile, have started ovulating again. There was no difference in survival rates between foals born to treated and untreated mares, and PZP treatment of pregnant mares did not affect subsequent fertility of their female offspring. |
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Address |
Science and Conservation Center, ZooMontana, Billings 59106, USA. zoolab@wtp.net |
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English |
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ISSN |
1477-0415 |
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Notes |
PMID:12220160 |
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Call Number |
refbase @ user @ |
Serial |
141 |
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Author |
Kirkpatrick, J.F.; Turner, A. |
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Title |
Absence of effects from immunocontraception on seasonal birth patterns and foal survival among barrier island wild horses |
Type |
Journal Article |
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Year |
2003 |
Publication |
Journal of applied animal welfare science : JAAWS |
Abbreviated Journal |
J Appl Anim Welf Sci |
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Volume |
6 |
Issue |
4 |
Pages |
301-308 |
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Keywords |
Animals; Animals, Newborn; Animals, Wild/*physiology; Birth Rate; Case-Control Studies; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; Horses/*physiology; Maryland/epidemiology; Membrane Glycoproteins/administration & dosage; Population Control; Pregnancy; *Receptors, Cell Surface; *Reproduction; Seasons; Vaccines, Contraceptive/administration & dosage |
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Abstract |
Despite a large body of safety data, concern exists that porcine zonae pellucidae (PZP) immunocontraception--used to manage wild horse populations--may cause out-of-season births with resulting foal mortality. Our study at Assateague, Maryland indicated the effects of immunocontraception on season of birth and foal survival between 1990 and 2002 on wild horses from Assateague Island. Among 91 mares never treated, 69 (75.8%) of foals were born in April, May, and June (in season). Among 77 treated mares, 50 (64.9%) were born in season. Of 29 mares foaling within 1 year after treatment (contraceptive failures), 20 (68.9%) were born in season. Of 48 mares treated for greater than 2 years then withdrawn from treatment, 30 (62.5%) of 48 foals were born in season. There were no significant differences (p <.05) between either treatment group or untreated mares. Survival did not differ significantly among foals born in or out of season or among foals born to treated or untreated mares. Data indicate a lack of effect of PZP contraception on season of birth or foal survival on barrier island habitats. |
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Address |
Science and Conservation Center Zoo Montana, Billings, Montana 59106, USA. jkirkpatrick@montana.net |
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English |
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ISSN |
1088-8705 |
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Notes |
PMID:14965784 |
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no |
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Call Number |
refbase @ user @ |
Serial |
140 |
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Author |
Kirkpatrick, J.F.; Turner, J.W.J.; Liu, I.K.; Fayrer-Hosken, R.; Rutberg, A.T. |
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Title |
Case studies in wildlife immunocontraception: wild and feral equids and white-tailed deer |
Type |
Journal Article |
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Year |
1997 |
Publication |
Reproduction, fertility, and development |
Abbreviated Journal |
Reprod Fertil Dev |
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Volume |
9 |
Issue |
1 |
Pages |
105-110 |
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Keywords |
Animals; Antigens/immunology; Contraception, Immunologic/*veterinary; *Deer; *Equidae; Female; Immunization, Secondary; Pest Control/*methods; Pregnancy; Swine; Vaccines/administration & dosage; Zona Pellucida/immunology |
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Abstract |
Non-lethal management methods are required for wild equids that are protected by law and for deer inhabiting areas where lethal controls are not legal or safe. Single or multiple inoculations of porcine zona pellucida (PZP) vaccine have been delivered to wild horses and deer by means of darts. Contraceptive efficacy in horses after two inoculations ranged from 90% to 100%, and after a single inoculation ranged from 19% to 28%. Mares given a controlled-release form of the vaccine had foaling rates ranging from 7% to 20%. No detectable changes in social organization or behaviours among treated horses occurred. Contraceptive effects were reversible after 4 consecutive years of treatment but 5-7 years of treatment resulted in ovulation failure and decreased urinary oestrogen concentrations. Among deer, two inoculations were 70-100% effective in preventing fawns, but one inoculation yielded a contraceptive efficacy of < or = 20%, with pregnancies occurring late in the breeding season; a single annual booster inoculation reduced fertility to 20% in the second year. Energy costs of extended breeding seasons were less than those resulting from pregnancy. After two years of treatment, ovaries appeared normal. These studies suggest that PZP immunocontraception can be successfully applied to certain free-roaming populations of wild horses and deer. |
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Address |
ZooMontana, Billings 59108, USA |
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English |
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ISSN |
1031-3613 |
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Notes |
PMID:9109199 |
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no |
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Call Number |
refbase @ user @ |
Serial |
143 |
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Author |
Crowell-Davis, S.L.; Houpt, K.A. |
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Title |
Maternal behavior |
Type |
Journal Article |
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Year |
1986 |
Publication |
The Veterinary clinics of North America. Equine practice |
Abbreviated Journal |
Vet Clin North Am Equine Pract |
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Volume |
2 |
Issue |
3 |
Pages |
557-571 |
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Keywords |
Aggression; Animals; Animals, Wild; Female; *Horses; Lactation; *Maternal Behavior; Pregnancy; *Pregnancy, Animal; Rejection (Psychology) |
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Abstract |
Parturition in mares is rapid and is followed by a brief period of sensitivity to imprinting on a foal. There is large individual variation in normal maternal style, but normal mothers actively defend their foal, remain near the foal when it is sleeping, tolerate or assist nursing, and do not injure their own foal. Disturbance of a mare and foal during the early imprinting period can predispose a mare to rejection of her foal; therefore, it should be avoided. There are a variety of forms of foal rejection and numerous etiologies. Therefore, each case should be evaluated individually. |
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English |
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Series Volume |
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Edition |
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ISSN |
0749-0739 |
ISBN |
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Notes |
PMID:3492245 |
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no |
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Call Number |
refbase @ user @ |
Serial |
49 |
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Author |
Boyd, L. |
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Title |
Behavior problems of equids in zoos |
Type |
Journal Article |
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Year |
1986 |
Publication |
The Veterinary clinics of North America. Equine practice |
Abbreviated Journal |
Vet Clin North Am Equine Pract |
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Volume |
2 |
Issue |
3 |
Pages |
653-664 |
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Keywords |
Aerophagy/veterinary; Aggression/psychology; Animals; *Animals, Zoo; *Behavior, Animal; Coprophagia/psychology; Female; *Horses; Impotence/veterinary; Male; Mastication; Motor Activity; *Perissodactyla; Pregnancy; Sexual Behavior, Animal; Social Environment |
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Abstract |
Behavior problems in zoo equids commonly result from a failure to provide for needs basic to equine nature. Equids are gregarious, and failure to provide companions may result in pacing. Wild equids spend 60 to 70 per cent of their time grazing, and failure to provide ad libitum roughage contributes to the problems of pacing, cribbing, wood chewing, and coprophagia. Mimicking the normal processes of juvenile dispersal, bachelor-herd formation, and mate acquisition reduces the likelihood of agonistic and reproductive behavior problems. Infanticide can be avoided by introducing new stallions to herds containing only nonpregnant mares and older foals. |
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English |
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ISSN |
0749-0739 |
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Notes |
PMID:3492252 |
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no |
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Call Number |
refbase @ user @ |
Serial |
660 |
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Author |
Turner, J.W.J.; Kirkpatrick, J.F. |
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Title |
Androgens, behaviour and fertility control in feral stallions |
Type |
Journal Article |
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Year |
1982 |
Publication |
Journal of reproduction and fertility. Supplement |
Abbreviated Journal |
J Reprod Fertil Suppl |
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Volume |
32 |
Issue |
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Pages |
79-87 |
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Keywords |
Animals; Animals, Wild; Copulation/drug effects; Female; *Fertility/drug effects; Horses/*physiology; Male; Periodicity; Pregnancy; Seasons; *Sexual Behavior, Animal/drug effects; Sexual Maturation; Sperm Count; Sperm Motility/drug effects; Testosterone/*blood/pharmacology |
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Abstract |
This field study of feral stallions in Montana and Idaho examines and correlates the seasonal pattern of plasma androgens and specific sociosexual behaviour and reports the effect of a long-acting androgenic steroid on this behaviour and on fertility. Plasma testosterone was measured by competitive protein binding assay in samples obtained by jugular venepuncture from captured animals. In samples taken from 34 sexually mature stallions in 6 different months during the year, a definite seasonal pattern in testosterone was present, with a peak in May (3.04 +/- 0.63 ng/ml) and a nadir in December (1.55 +/- 0.34 ng/ml). Values were less than 2.0 ng/ml in non-breeding months and greater than 2.4 ng/ml in breeding months. Behavioural endpoints measured were (1) stallion scent marking in response to elimination by mares (elimination marking), (2) mounting and (3) copulation. The frequencies of each of these endpoints followed closely the seasonal pattern seen for plasma androgens. In the fertility study microcapsulated testosterone propionate (microTP) was administered i.m. to 10 harem stud stallions 3 months before the 1980 breeding season. In these stallions and in 10 control harem studs, the above behavioural endpoints were examined in the 1980 and 1981 breeding seasons, and foal counts were made in 1981. There were no direct inhibitory or stimulatory effects of microTP treatment on any of the behavioural endpoints in either year. In 1981 foals were produced in 87.5% of the control bands and 28.4% of the microTP-treated bands. These results indicate that microencapsulated testosterone propionate can provide effective fertility control in feral horses without causing significant alterations in sociosexual behaviour. |
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English |
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Series Volume |
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Edition |
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ISSN |
0449-3087 |
ISBN |
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Notes |
PMID:6962905 |
Approved |
no |
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Call Number |
refbase @ user @ |
Serial |
138 |
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Author |
Schwarzenberger, F.; Mostl, E.; Bamberg, E.; Pammer, J.; Schmehlik, O. |
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Title |
Concentrations of progestagens and oestrogens in the faeces of pregnant Lipizzan, trotter and thoroughbred mares |
Type |
Journal Article |
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Year |
1991 |
Publication |
Journal of reproduction and fertility. Supplement |
Abbreviated Journal |
J Reprod Fertil Suppl |
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Volume |
44 |
Issue |
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Pages |
489-499 |
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Keywords |
Animals; Estrogens/*analysis; Feces/*chemistry; Female; Gestational Age; Horses/*metabolism; Immunoenzyme Techniques; Labor, Obstetric; Pregnancy; Pregnancy, Animal/*metabolism; Pregnenes/analysis; Progestins/*analysis |
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Abstract |
Faecal samples were collected at weekly intervals from pregnant Lipizzan mares during Weeks 7-16 following mating and from Lipizzan, Trotter and Thoroughbred mares during the last 3 months of gestation. After parturition, samples were taken daily from the Thoroughbred mares for another 6 days. Non-pregnant mares served as controls. The concentrations of unconjugated oestrogens (Eg), 20 alpha-OH-progestagens (20 alpha-G) and 20 beta-OH-progestagens (20 beta-G) were measured by enzyme immunoassay. In the faeces of Lipizzan mares, immunoreactive progestagens were significantly (P less than 0.01) elevated above the levels in non-pregnant mares by Week 11, and Eg by Week 13 of pregnancy onwards. During the last 3 months of gestation, concentrations of Eg were significantly higher in Trotter mares than in Lipizzan and Thoroughbred mares. Concentrations of 20 alpha-G and 20 beta-G increased to maximal values in the last month of gestation. There was no significant difference among the 3 breeds with respect to 20 alpha-G but, during the 10 weeks before parturition, concentrations of 20 beta-G in the Lipizzan mares were significantly lower (P less than 0.05) than those in the Thoroughbred mares. They were also significantly lower than those of the Trotter mares during the last 4 weeks of gestation. After parturition, the concentrations of Eg and progestagens had declined to baseline values by Days 3 and 4 respectively. From these results we conclude that high concentrations of progestagens with 20 alpha- and 20 beta-hydroxyl groups are present in the faeces of pregnant mares, especially during the last month of gestation. |
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Address |
Institut fur Biochemie, Veterinary Medical University, Vienna, Austria |
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English |
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0449-3087 |
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Notes |
PMID:1795293 |
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no |
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Call Number |
refbase @ user @ |
Serial |
322 |
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Author |
Belonje, P.C.; van Niekerk, C.H. |
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Title |
A review of the influence of nutrition upon the oestrous cycle and early pregnancy in the mare |
Type |
Journal Article |
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Year |
1975 |
Publication |
Journal of Reproduction and Fertility. Supplement |
Abbreviated Journal |
J Reprod Fertil Suppl |
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Volume |
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Issue |
23 |
Pages |
167-169 |
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Keywords |
Animals; Body Weight; *Diet; *Estrus; Female; Fertility; Fetal Resorption/prevention & control; Horses/*physiology; Pregnancy |
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Abstract |
Attention is drawn to the beneficial effect of improved nutrition during winter and early spring on the ovarian activity of mares. Furthermore, the necessity of an adequate plane of nutrition during early pregnancy to prevent embryonic resorption is stressed. |
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English |
Summary Language |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0449-3087 |
ISBN |
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Notes |
PMID:1060772 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2225 |
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Author |
Lucas, Z.; Raeside, J.I.; Betteridge, K.J. |
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Title |
Non-invasive assessment of the incidences of pregnancy and pregnancy loss in the feral horses of Sable Island |
Type |
Journal Article |
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Year |
1991 |
Publication |
Journal of Reproduction and Fertility. Supplement |
Abbreviated Journal |
J Reprod Fertil Suppl |
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Volume |
44 |
Issue |
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Pages |
479-488 |
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Keywords |
Abortion, Veterinary/*epidemiology; Animals; Animals, Wild/*physiology; Atlantic Islands; Estrogens/analysis; Feces/chemistry; Female; Fertilization; Gestational Age; Horse Diseases/*epidemiology; Horses; Incidence; Pregnancy; *Pregnancy, Animal |
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Abstract |
Field observations of 400 totally unmanaged feral horses on Sable Island, Nova Scotia, were complemented by oestrogen determinations in faecal samples from 154 identified females over a 4-year period (454 mare-years). Of mares that were sampled throughout the year and subsequently produced foals, 92.1% exhibited elevated faecal oestrogens between 15 October and 30 March. The results confirm that faecal oestrogens are a useful indicator of pregnancy after approximately 120 days gestation. Distribution of foaling resembled that seen in other feral populations, with 95% of births occurring from April through July. The foaling rate for mares aged 3 years or older was 62.0%, with 50.7% of mares foaling in 3 or 4 years. Foaling rates were low (4.1%) in mares bred as yearlings and rose with age to 70.8% in those bred as 4-year-olds. Fetal loss after Day 120 was deduced from faecal oestrogens to be 26.0% overall, with marked variation from year to year (9.6-37.3%) and with age (70.0% in those bred as yearlings, decreasing to 5.6% in those bred as 4-year-olds). Of 58 mares aged 2 years or older that were sampled every year, about half (49.6%) the barren years were attributable to fetal loss after 120 days gestation. All mares conceived in at least 2 of the 4 years, suggesting that pregnancy loss, even after Day 120, is as important as failure to conceive in causing barren years. |
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Address |
Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Canada |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
0449-3087 |
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Conference |
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Notes |
PMID:1795292 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2247 |
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