Seasonality of Boer goats in northern Europe and induction of estrus out of season
MetadataShow full item record
Seasonality in Boer goats in Northern Europe and attempts to overcome it is addressed in three studies. In Experiment 1, monitoring of estrus and serum progesterone,concentration in sexually mature nulliparous Boer goat crosses indicated that ovarian activity ceased in February/March and was resumed from August onward. In 63.7% of 22 does the first estrus of the season was preceded by one or two ovulations, indicated by an increase in progesterone; in 22.7% first estrus and first ovulation coincided and in the remaining 13.6% the first estrus was not succeeded by formation of a functional corpus luteum. In Experiment 2, 31 Boer goats, weaned between July and September, were treated with progestogen-containing intravaginal sponges and 250 IU eCG either one (n = 11), seven (n = 10) or fourteen (n = 10) days after weaning. All but two does showed estrous symptoms and were naturally mated. Transrectal ultrasonography 45 days after mating revealed a pregnancy rate of 42%. All of these carried to term (36% treated immediately after weaning, 40% treated one week later and 50% treated two weeks later) and gave birth to, on average, 2.1 kids. In Experiment 3, of 18 nulliparous does, 9-12 months of age, subjected to progestogen-eCG treatment out-of-season, 15 (83%) responded by showing estrous symptoms; 14 were naturally mated and six were diagnosed as pregnant five weeks later. One of the pregnant does aborted two weeks before parturition was due; in the others pregnancy had ceased at an earlier stage without visible symptoms. In conclusion, in northern Europe, Boer goats undergo a period of reduced ovarian activity, although to a lesser degree than dairy breeds. In most cases acyclicity was overcome by hormonal stimulation and, if mated, part of the weaned does carried to term, whereas in young nulliparous does pregnancy was not maintained.
Showing items related by title, author, creator and subject.
Seasonal dynamics of root uptake and spring remobilisation of nitrogen in field grown orange trees Roccuzzo G; Scandellari F; Allegra M; Torrisi B; Stagno F; Mimmo T; Zanotelli D; Gioacchini P; Millard P; Tagliavini M (2017)To be economically and environmentally sound, the nitrogen (N) supply in orchards needs to be finely tuned according to crop needs. This requires knowledge of the amount and the dynamics of N uptake by roots and of its ...
Climate warming increases vertical and seasonal water temperature differences and inter-annual variability in a mountain lake Niedrist GH; Psenner R; Sommaruga R (2018)Lakes around the world are warming, but not all water layers are warming at the same rate, and some are even cooling. Most studies have focused on summer lake water surface temperatures or analyzed short-time series. Here, ...
Evaluation of Seasonal Variability of Toxic and Essential Elements in Urine Analyzed by Inductively Coupled Plasma Mass Spectrometry Paglia G; Miedico O; Tarallo M; Lovino A; Astarita G; Chiaravalle AE; Corso G (2016)Human exposure to elements is a process difficult to control and monitor. Studies on this topic usually rely on single spot urine sample to assess exposure, with the risk of ignoring variability over a longer period. In ...