Differences in seasonal changes of fecal androgen levels between stabled and free-ranging Polish Konik stallions
Department of Animal Physiology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland. General and Comparative Endocrinology
(Impact Factor: 2.47).
09/2010; 168(3):455-9. DOI: 10.1016/j.ygcen.2010.06.004
Blood and feces samples were collected from Polish Konik stallions kept under conventional stable conditions and in the forest reserve during a 1-year study period. Levels of testosterone (T) and androstenedione (A(4)) were measured using radioimmunoassay. Positive correlation between fecal and plasma concentrations of androgens was observed. Fecal T concentrations increased in April and May reaching peak value mid-April in the stallions from the reserve group and 2 weeks later in the stallions from the stable group. Comparatively, concentrations of T were higher in the stable group. Levels of T decreased in July, increasing through August to September, and decreasing again in October. During this period of increase, concentrations of T were higher in the reserve group. A peak of fecal A(4) concentrations in the reserve group was noted mid-April, but high levels of this androgen appeared later and remained longer (also in May). When the breeding season finished, the concentration of A(4) decreased and remained low. During breeding season, concentrations of A(4) were higher in fecal samples taken from stable stallions than from those in the reserve group. During non-breeding seasons levels of this androgen in both groups were similar. The individual differences in the fecal androgen levels were dependent on the behavior of the stallions and were not related to their age. The seasonal changes of fecal T and A(4) levels differed between stabled and free-ranging Polish Konik stallions.
Available from: Artur Niedźwiedź
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ABSTRACT: The aim of this study was to investigate the causes of chronic respiratory disorders in Polish Konik horses maintained in a stable and pasture, under condition typical for pleasure horses in Poland. The study was conducted on 14 adult horses, consistent with regard to environment and living conditions. The horses were divided into two groups: seven horses not affected by any respiratory problem (control group) and seven horses with history of lower airway disease (study group). Clinical and laboratory evaluation, endoscopic examination, bronchoalveolar lavage, tracheal wash, and lung ultrasound were performed in all horses. Median (25 th and 75 th percentiles) for bronchoalveolar lavage fluid differential cell count in control horses was 55.8 (49.8 and 59.1) of macrophages, 41 (38.5 and 45.9) of lymphocytes, and 5.1 (4.1 and 5.3) of neutrophils, whereas in the study group they were 32.8 (25.9 and 35.7) of macrophages, 59.8 (51.3 and 64.8) of lymphocytes, and 38.1 (34.8 and 41.1) of neutrophils. It was concluded that chronic respiratory disorders in Polish Konik horses were probably caused by recurrent airway obstruction.
Available from: Bogumiła Pilarczyk
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ABSTRACT: The aim of this study was to determine serum selenium concentrations in Polish Konik horses residing in the Odra Delta Nature Park (Poland) and to evaluate the activity of glutathione peroxidase and Se content in testes of this horse breed. In over 95% of cases, serum Se concentration was below the optimal range, and none of the horses examined was deficient in this trace element. The lack of Se deficiency in the animals examined suggests however, that the Polish Konik horses have a natural ability to the optimal use of nutrients available in their life area. Testicular content of Se and GSHPx activity in the colts was higher than those found in stallions, and a positive relationship between these antioxidants was demonstrated. The differences in Se contents and GSHPx activities in testes between colts and stallions suggest that selenoenzymes play important roles during the puberty of male horses.
Available from: Tadeusz Jezierski
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ABSTRACT: The aim of this preliminary study was to assess whether adult stallions differentiate their olfactory and marking behavior towards the excreta of potential rivals depending on their age, libido, hormonal status and the season of the year. Five Konik stallions were individually exposed to their own and each others’ feces in a round pen during eight observation sessions from February to November. The youngest stallion’s feces were sniffed for a significantly longer period and were defecated/urinated upon significantly more often, in addition to receiving more flehmen reactions. The stallion with the highest libido sniffed feces significantly longer. Alien feces were sniffed significantly longer than an individual’s own feces, except for the youngest stallion. Overmarking of existing feces with urine was significantly less frequent than through defecation and was observed only outside of the reproductive season. Defecations upon feces were most frequent after the peak of the reproductive season. A stallion’s libido rank correlated perfectly with the number of defecations performed upon alien feces (rs=1.000). Sniffing of feces occurred for a longer time prior to the peak of the reproductive season, and flehmen was performed primarily on spots around feces and significantly more often in the peak of the reproductive season (May). Fecal testosterone and androstenedione concentrations were significantly higher in April and May but did not differ significantly between stallions. Testosterone concentrations were positively correlated with duration of performed sniffing feces and negatively correlated with the duration the individual’s feces were sniffed. It was for the first time shown which individual social information could be mediated by defecation and sniffing feces in adult stallions.
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