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Author (down) Lee, R.D. doi  openurl
  Title Rethinking the evolutionary theory of aging: transfers, not births, shape senescence in social species Type Journal Article
  Year 2003 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc Natl Acad Sci U S A  
  Volume 100 Issue 16 Pages 9637-9642  
  Keywords Adaptation, Physiological; *Aging; Animals; *Biological Evolution; Demography; Economics; Environment; Fertility; Humans; Life Expectancy; Longevity; Models, Theoretical; Parturition; Population Dynamics; Population Growth; Reproduction  
  Abstract The classic evolutionary theory of aging explains why mortality rises with age: as individuals grow older, less lifetime fertility remains, so continued survival contributes less to reproductive fitness. However, successful reproduction often involves intergenerational transfers as well as fertility. In the formal theory offered here, age-specific selective pressure on mortality depends on a weighted average of remaining fertility (the classic effect) and remaining intergenerational transfers to be made to others. For species at the optimal quantity-investment tradeoff for offspring, only the transfer effect shapes mortality, explaining postreproductive survival and why juvenile mortality declines with age. It also explains the evolution of lower fertility, longer life, and increased investments in offspring.  
  Address Department of Demography, University of California, 2232 Piedmont Avenue, Berkeley, CA 94720-2120, USA. rlee@demog.berkeley.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12878733 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5465  
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Author (down) Klingel, H. openurl 
  Title Social organization and reproduction in equids Type Journal Article
  Year 1975 Publication Journal of Reproduction and Fertility. Supplement Abbreviated Journal J Reprod Fertil Suppl  
  Volume Issue 23 Pages 7-11  
  Keywords Animals; Behavior, Animal; Female; Male; Perissodactyla/*physiology; Reproduction; *Sexual Behavior, Animal; Social Behavior; Territoriality  
  Abstract There are two distinct types of social organization and, accordingly, two types of mating systems in equids. In the horse, Plains zebra and Mountain zebra, the adults live in non-territorial and cohesive one-male groups and in stallion groups. The family stallions have exclusive mating rights which are respected by all others. In Grevy's zebra and in the African and Asiatic wild asses, the stallions are permanently territorial and have exclusive mating rights within their territories. Ecological and evolutionary aspects are discussed.  
  Address  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0449-3087 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1060868 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2303  
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Author (down) Kirkpatrick, J.F.; Turner, A. doi  openurl
  Title Absence of effects from immunocontraception on seasonal birth patterns and foal survival among barrier island wild horses Type Journal Article
  Year 2003 Publication Journal of applied animal welfare science : JAAWS Abbreviated Journal J Appl Anim Welf Sci  
  Volume 6 Issue 4 Pages 301-308  
  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  
  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.  
  Address Science and Conservation Center Zoo Montana, Billings, Montana 59106, USA. jkirkpatrick@montana.net  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1088-8705 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:14965784 Approved no  
  Call Number refbase @ user @ Serial 140  
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Author (down) Khalil, A.M.; Murakami, N.; Kaseda, Y. openurl 
  Title Relationship between plasma testosterone concentrations and age, breeding season and harem size in Misaki feral horses Type Journal Article
  Year 1998 Publication The Journal of veterinary medical science / the Japanese Society of Veterinary Science Abbreviated Journal J Vet Med Sci  
  Volume 60 Issue 5 Pages 643-645  
  Keywords Age Factors; Animals; Animals, Wild; *Horses; Japan; Male; Reproduction; Seasons; Sexual Behavior, Animal; Sexual Maturation; *Social Behavior; Testosterone/*blood  
  Abstract Jugular vein blood samples were collected from 23 young and sexual mature feral stallions to examine the relationship between plasma testosterone concentration and age, breeding season or harem size. Testosterone concentration increased with the age of the stallions until they formed their own harems, at about 4 to 6 years old. Seasonal variations in testosterone concentrations were observed, and found to be significantly higher (P<0.001) throughout the breeding season than non-breeding season, from 3 years of age. Testosterone levels were correlated with harem size for individual stallions. It can be inferred from these results that there is a relationship between plasma testosterone concentration and age, breeding season and harem size.  
  Address Laboratory of Animal Behavioral Science, Faculty of Agriculture, Miyazaki University, Japan  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0916-7250 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:9637303 Approved no  
  Call Number refbase @ user @ Serial 137  
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Author (down) Keiper, R.; Houpt, K. openurl 
  Title Reproduction in feral horses: an eight-year study Type Journal Article
  Year 1984 Publication American journal of veterinary research Abbreviated Journal Am J Vet Res  
  Volume 45 Issue 5 Pages 991-995  
  Keywords Abortion, Veterinary/epidemiology; Anestrus; Animal Population Groups/*physiology; Animals; Animals, Wild/*physiology; Birth Rate; Female; Fertility; Horse Diseases/epidemiology; Horses/*physiology; Lactation; Male; Maryland; Pregnancy; *Reproduction; Seasons; Sex Ratio; Virginia  
  Abstract The reproductive rate and foal survival of the free-ranging ponies on Assateague Island National Seashore were studied for 8 years, 1975 to 1982. Most (52%) of the 86 foals were born in May, 13% were born in April, 22.6% in June, 10.4% in July, and less than 1% in August and September. The mean foaling rate was 57.1 +/- 3.9% and the survival rate was 88.3 +/- 3.6%. Forty-eight colts and 55 fillies were born (sex ratio 53% female). Mares less than 3 years old did not foal and the foaling rate of 3-year-old mares was only 23%, that of 4-year-old mares was 46%, that of 5-year-old mares was 53%, and 6-year-old mares was 69%. The relatively poor reproduction rate was believed to be a consequence of the stress of lactating while carrying a foal when forage quality on the island was low. The hypothesis was supported by the higher reproductive rate (74.4 +/- 2.4%) of the ponies in the Chincoteague National Wildlife Refuge on the southern part of the island. Their foals are weaned and sold in July each year. Despite the low reproductive rate on Assateague Island National Seashore , the number of ponies increased from 43 to 80, a 90% increase in the 8-year period or greater than 10%/yr. There were 24 deaths and 8 dispersals from the study area.  
  Address  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0002-9645 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6732036 Approved no  
  Call Number refbase @ user @ Serial 665  
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Author (down) Kaseda, Y.; Ogawa, H.; Khalil, A.M. url  doi
openurl 
  Title Causes of natal dispersal and emigration and their effects on harem formation in Misaki feral horses Type Journal Article
  Year 1997 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 29 Issue 4 Pages 262-266  
  Keywords Age Factors; Animal Migration; Animals; Animals, Wild; *Behavior, Animal/physiology; Female; Horses/*physiology/psychology; Male; Reproduction; Seasons; Sexual Behavior, Animal; *Social Behavior  
  Abstract Misaki feral horses were separated into 2 herds and the difference between dispersal from natal group (natal dispersal) and dispersal from natal area (natal emigration) was studied. The causes of dispersal and emigration and their effects on harem formation were studied 1979-1994. The number of horses ranged from 73 (mature males: 8, mature females: 26, young males: 8, young females: 3, colt foals: 6, filly foals: 10 and geldings: 12) in 1979 and 86 (mature males: 14, mature females: 37, young males: 12, young females: 7, colt foals: 5, filly foals: 7 and geldings: 4) in 1994 when the present study ended. All 29 males which survived to age 4 years and 58 females which survived to age 3 years left their natal or mother groups at age one to 3. Seventeen of 22 dispersing males and 29 of 39 dispersing females left their natal groups around the birth of their siblings and significant correlations were found between natal dispersal and birth of a sibling. The number of emigrating young males correlated negatively and significantly with the total number of young males in another herd and the number of emigrating young females correlated positively and significantly with the total number of young females in the natal herd. All 13 emigrating stallions which survived to age 5 years formed stable harem groups and a significant correlation was found between natal emigration and harem formation. Twenty-three of 35 resident mares formed stable consort relations with harem stallions and a significant correlation was found between residence and formation of stable consort relations.  
  Address Faculty of Agriculture, Miyazaki University, Miyazaki-shi, 889-21, Japan  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15338905 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4630  
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Author (down) Kaseda, Y.; Khalil, A.M. url  doi
openurl 
  Title Harem size and reproductive success of stallions in Misaki feral horses Type Journal Article
  Year 1996 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 47 Issue 3-4 Pages 163-173  
  Keywords Harem size; Horse social organization; Reproduction; Blood types; Misaki feral horse  
  Abstract Over a 16-year period (1979-1994), long-term investigations were carried out on 14 Misaki feral stallions to analyze changes in harem size and the reproductive success. Harem size changed with the age of the stallions. Most stallions formed harem groups with four to five mares at the age of 4-6 and then the number of mares increased rapidly to the maximum at the age of 6-9 years. Thereafter, harem size decreased gradually to a minimum with advancing age. The harem size of 60 stable harem groups ranged from 1 to 9, and the average varied from a minimum mean of 1.8 in 1988 to a maximum mean of 5.3 in 1982. Mean harem size increased as adult sex ratio increased and a significant and positive correlation was found between them. One hundred and ninety-eight sire-foal pairs were determined by a paternity test with blood types and consort relations between stallions and mares during the study period. Out of 99 foals which were born in the stable harem groups, the true sires of 84 foals (85%) were the harem stallions in which the foals were born but the remaining 15 foals (15%) were sired by other harem stallions. Two out of three stallions which were studied throughout their lifetime produced 24 and 25 foals in 10 and 11 years of their reproductive lifespan, respectively. Another one produced only five foals in 6 years. The number of foals sired by the harem stallions was less than two over harem size 7 and some of the foals born in the harem were sired by other harem stallions. These results suggest that if a particular stallion monopolizes too many mares, he could not sire so many offspring because he could not always prevent his rival stallions from mating with his mares in wild or feral circumstances.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 2308  
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Author (down) Kampmann, S.; Hampson, B.A.; Pollitt, C.C. url  doi
openurl 
  Title Population dynamics of feral horses (Equus caballus) following above-average rainfall in a semi-arid environment of Australia Type Journal Article
  Year 2013 Publication Australian Veterinary Journal Abbreviated Journal Aust Vet J  
  Volume 91 Issue 11 Pages 482-487  
  Keywords animal welfare; ecology; horses; reproduction; wildlife  
  Abstract Background Recent record rainfall in much of semi-arid Central Australia is the most likely reason for a feral horse population increase in excess of normal. Uncontrolled numbers of feral horses have habitat degradation and animal welfare implications. Objectives The aims of this study were to investigate the social structure of feral horses and assess their population growth rate following unseasonably high rainfall. Methods The study area was 4000 km2 of unmanaged, semi-arid country in Central Australia (latitude 24.50°S, longitude 132.10°E). Horses were identified by descriptive features from ground searches, movement-activated cameras and ‘hides’ positioned at key water holes. Wherever possible, sex and age categories were documented. Population growth rate was estimated by the number of foals divided by the number of horses older than 1 year in the observed population. Results A total of 1424 horses were identified and categorised, of which 335 were foals born within the current year. Only 123 juveniles were identified. Of the adult horses, 53.4% were male and 46.6% were female and this differed from parity (P = 0.04). Of the mares, 71.9% had a foal at foot and the population growth rate was 29.5%. Conclusions With a sustained population growth rate of 29.5%, this population of feral horses will more than double within 3 years. The high population increase will likely have a detrimental effect on native fauna and flora and the fragile, semi-arid ecosystems of Central Australia. After a period of high rainfall and plentiful resources, ‘normal’ drought conditions will return and many feral horses will starve and die as they compete for limited resources.  
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  ISSN 1751-0813 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5747  
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Author (down) Howard, R.W.; Blomquist, G.J. url  doi
openurl 
  Title Ecological, behavioral, and biochemical aspects of insect hydrocarbons Type Journal Article
  Year 2005 Publication Annual Review of Entomology Abbreviated Journal Annu Rev Entomol  
  Volume 50 Issue Pages 371-393  
  Keywords Animals; Behavior, Animal/physiology; Hydrocarbons/*metabolism; Insects/*physiology; Pheromones/*physiology; Reproduction; Species Specificity  
  Abstract This review covers selected literature from 1982 to the present on some of the ecological, behavioral, and biochemical aspects of hydrocarbon use by insects and other arthropods. Major ecological and behavioral topics are species- and gender-recognition, nestmate recognition, task-specific cues, dominance and fertility cues, chemical mimicry, and primer pheromones. Major biochemical topics include chain length regulation, mechanism of hydrocarbon formation, timing of hydrocarbon synthesis and transport, and biosynthesis of volatile hydrocarbon pheromones of Lepidoptera and Coleoptera. In addition, a section is devoted to future research needs in this rapidly growing area of science.  
  Address USDA-ARS, Manhattan, Kansas 66502, USA. howardks@ksu.edu  
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  ISSN 0066-4170 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15355247 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4650  
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Author (down) Henneke, D.R.; Potter, G.D.; Kreider, J.L.; Yeates, B.F. doi  openurl
  Title Relationship between condition score, physical measurements and body fat percentage in mares Type Journal Article
  Year 1983 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 15 Issue 4 Pages 371-372  
  Keywords *Adipose Tissue; Animals; Biometry; Body Weight; Female; Heart/anatomy & histology; Horses/anatomy & histology/*physiology; *Reproduction  
  Abstract  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6641685 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2299  
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