scholarly journals Effects of Litter Size on Gestation Length and Plasma Progesterone Concentration in Mongolian Gerbils (Meriones unguiculatus)

1999 ◽  
Vol 70 (1) ◽  
pp. 18-23
Author(s):  
Osamu KAI ◽  
Yutaka SONODA ◽  
Naoto SENSUI ◽  
Kiyoshi IMAI
2021 ◽  
Vol 6 (2) ◽  
pp. 80-87
Author(s):  
Intan Sofienaz Ahmad Fuad ◽  
Khairiyah Mat ◽  
Nor Dini Rusli ◽  
Hasnita Che Harun

This experiment goal was to identify the effect of parity and body condition score (BCS) on oestrusexpressions (OE), post breeding reproductive performance (PBRP) of Katjang crossbred andchanges of progesterone (P4) concentration. Twenty-four does were treated with 14 dayssynchronisation followed by visual observation of oestrus expressions (standing heat (SH),mounted by other buck but not standing (MBNS), vocalization (VC), tail swaging (TW), andsniffing of the genital of other buck (SGB)) and blood sampling twice daily up to 72 hours followingControl Internal Drug Release (CIDR) removal. PBRP data was recorded for evaluation whichincluded pregnancy rate (PR), abortion rate (AR), mortality rate (MR), litter size (LS), litter birthweight (LBW) and gestation length (GL). Result revealed that there was no significant effect(P>0.05) of parity and BCS on OE, PBRP and progesterone concentration except for birth weightwhich had been affected by parity. Based on observation of OE of SH, it was found that accuracyof pregnancy prediction was up to 50%. Analysis of OE established reliability of OE in wassequence from SH>SGB>TW>MBNS>VC and onset of oestrus began approximately 33h post toCIDR removal. Analysis of PBRP shown parity?2 had heavier birth weight in single litter size thanparity?3 which was associated with no MR. Progesterone concentration indicated all of the doeswere on oestrus and highly susceptible as early as 48 h post to CIDR removal. In conclusion, thisstudy demonstrated that both non-genetic factors; parity and BCS are very poor in determining theeffect of OE, PBRP and P4 concentration due to limitation of sample size and greater influences ofexternal factors such as weather, extreme environmental condition and farm management. It isrecommended to improve program in future by focusing on enhancing the fertilization rate andreducing embryonic loss for optimum conception rate.


1997 ◽  
Vol 46 (2) ◽  
pp. 157-159 ◽  
Author(s):  
Osamu KAI ◽  
Yohko HIRAMATSU ◽  
Yutaka SONODA ◽  
Naoto SENSUI ◽  
Kiyoshi IMAI

Reproduction ◽  
2009 ◽  
Vol 137 (1) ◽  
pp. 107-117 ◽  
Author(s):  
E M Menkhorst ◽  
L A Hinds ◽  
L Selwood

Close examination of hormonal profiles and uterine morphology in the marsupial reproductive cycle highlights significant differences between pregnant and non-pregnant cycles. In the polyovular dasyurid marsupial Sminthopsis macroura, we identified changes associated with gestation by comparing ovarian and plasma progesterone concentrations, uterine weights, uterine epithelial mitoses, body weights and gestation lengths between pregnant and non-pregnant luteal phases. The plasma progesterone profile of S. macroura was biphasic, peaking during unilaminar blastocyst expansion and on the day of implantation. Periods of rapid embryonic development were associated with increasing plasma progesterone concentrations and animal body weight. For the first time in a polyovular marsupial, we identified 1) a correlation between ovarian progesterone concentration and conceptus number during the luteal phase just prior to implantation (total ovarian progesterone), indicating a conceptus influence on progesterone concentration; 2) a pulse of uterine epithelial mitotic activity at the time of implantation and 3) increased mitotic activity in pregnant animals during unilaminar blastocyst formation compared with non-pregnant animals. Gestation length was reduced by up to 15%, due to the loss of, or reduction in, the four-cell arrest and more rapid definitive blastocyst expansion. This is the first time a conceptus influence on gestation length has been identified in a dasyurid. This study provides further evidence for the modification of the luteal phase by pregnancy in S. macroura.


1988 ◽  
Vol 60 (6) ◽  
pp. 554-556
Author(s):  
B. Reklewska ◽  
Z. J. Tyszka ◽  
R. Niznikowski

The aim of the study was to evaluate the relationship between the litter size and plasma progesterone (PP) concentration during the breeding season and pregnancy in some prolific sheep breeds. Investigations were performed during two consecutive reproductive cycles. PP concentrations were determined in Finnsheep (n = 16), Polish Heath (n = 13), Friesian (n = 10), Zelazna (n = 12) and Karakul (n = 14). Prolificacy was 3.14, 2.0, 2.0, 1.8 and 1.12, resp. Highly significant differences in PP levels during pregnancy were found between the prolific breeds and breed with the lowest litter size. There was also a significant effect of pregnancy stage on the PP concentration. Breed differences in PP levels during the oestrus cycle were the most pronounced on the 10th day of the cycle. However, due to a considerable variation within breeds they were statistically insignificant.


2016 ◽  
Vol 59 (1) ◽  
pp. 145-150 ◽  
Author(s):  
Ewa Kuźnicka ◽  
Witold Rant ◽  
Aurelia Radzik-Rant ◽  
Małgorzata Kunowska-Slósarz ◽  
Marek Balcerak

Abstract. A herd of sheep (40 heads) was divided into two equal groups: group 1 was kept under an overhead shelter and group 2 in a warm barn. The effect of maintenance on ewe's reproductive performance, corpora lutea and corpora lutea of pregnancy rate, as well as the concentration of plasma progesterone and estradiol in peripheral blood was investigated. At the first laparoscopy fewer corpora lutea than during the following one were observed (P ≤ 0.01). In sheep kept under the overhead shelter, a greater number of corpora lutea were noted. More corpora lutea of pregnancy were observed in group 1 than in the group from the barn. On the first day after mating the average level of progesterone was 190 pg mL−1, and after 2 weeks it increased to more than 300 pg mL−1 (P ≤ 0.01). The positive correlation between the number of corpora lutea of pregnancy and progesterone concentration (P ≤ 0.01) and the negative correlation (P ≤ 0.01) with number of corpora lutea of pregnancy, as well as between the litter size and estradiol concentration, were observed. Harsh environmental conditions did not cause a significant decrease of the reproduction performance of ewes kept under the overhead shed.


1967 ◽  
Vol 55 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Benno Runnebaum ◽  
Josef Zander

ABSTRACT Progesterone was determined and identified in human peripheral blood during the preovulatory period of the menstrual cycle, by combined isotope derivative and recrystallization analysis. The mean concentration of progesterone in 1.095 ml of plasma obtained 9 days before ovulation was 0.084 μg/100 ml. However, the mean concentration of progesterone in 1.122 ml of plasma obtained 4 days before ovulation was 0.279 μg/100 ml. These data demonstrate a source of progesterone secretion other than the corpus luteum. The higher plasma-progesterone concentration 4 days before ovulation may indicate progesterone secretion of the ripening Graafian follicle of the ovary.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 454
Author(s):  
Jaime Palomino ◽  
Javiera Flores ◽  
Georges Ramirez ◽  
Victor H. Parraguez ◽  
Monica De los Reyes

The gene expression in the canine oviduct, where oocyte maturation, fertilization, and early embryonic development occur, is still elusive. This study determined the oviductal expression of (PR), cyclooxygenase-2 (COX-2), growth differentiation factor 9 (GDF-9), and bone morphogenetic protein 15 (BMP-15) during the canine oestrous cycle. Samples were collected from bitches at anoestrus (9), proestrus (7), oestrus (8), and dioestrus (11), after routine ovariohysterectomy and the ovarian surface structures and plasma progesterone concentration evaluated the physiological status of each donor. The oviductal cells were isolated and pooled. Total RNA was isolated, and gene expression was assessed by qPCR followed by analysis using the t-test and ANOVA. The PR mRNA increased (P < 0.05) from the anoestrus to dioestrus with the plasma progesterone concentration (r = 0.8). COX-2 mRNA expression was low in the anoestrus and proestrus, and negligible in the oestrus, while it was around 10-fold higher (P < 0.05) in the dioestrus. The GDF-9 mRNA was expressed during all phases of the oestrous cycle and was most abundant (P < 0.05) during oestrus phase. The BMP-15 mRNA decreased (P < 0.05) in the anoestrus and proestrus phases. Thus, the transcripts were differentially expressed in a stage-dependent manner, suggesting the importance of oestrous cycle regulation for successful reproduction in dogs.


Author(s):  
N Fetherstone ◽  
N McHugh ◽  
T M Boland ◽  
F M McGovern

Abstract The objective of this study was to investigate the impact of the ewe’s maternal genetic merit and country of origin (New Zealand or Ireland) on ewe reproductive, lambing and productivity traits. The study was performed over a four year period (2016 to 2019) and consisted of three genetic groups: high maternal genetic merit New Zealand (NZ), high maternal genetic merit Irish (High Irish) and low maternal genetic merit Irish (Low Irish) ewes. Each group contained 30 Suffolk and 30 Texel ewes, selected based on the respective national maternal genetic indexes; i.e. either the New Zealand Maternal Worth (New Zealand group) or the €uro-star Replacement index (Irish groups). The impact of maternal genetic merit on reproductive traits such as litter size; lambing traits such as gestation length, birth weight, lambing difficulty, mothering ability, and productivity traits such as the number of lambs born and weaned were analyzed using linear mixed models. For binary traits, the impact of maternal genetic merit on reproductive traits such as conception to first AI service; lambing traits such as dystocia, perinatal lamb mortality and productivity traits such as ewe survival were analyzed using logistic regression. New Zealand ewes outperformed Low Irish ewes for conception to first AI (P&lt;0.05) and litter size (P=0.05). Irish ewes were more likely to suffer from dystocia (6.84 (High Irish) and 8.25 (Low Irish) times) compared to NZ ewes (P&lt;0.001); birth weight and perinatal mortality did not differ between groups (P&gt;0.05). Lambs born from NZ ewes were 4.67 (95% CI: 1.89 to 11.55; P&lt;0.001) and 6.54 (95% CI: 2.56 to 16.71; P&lt;0.001) times more likely to stand up and suckle unassisted relative to lambs born from High or Low Irish ewes, respectively. New Zealand and High Irish ewes had a greater number of lambs born and weaned throughout the duration of the study compared to their Low Irish counterparts (P&lt;0.001). New Zealand ewes tended to be more likely to survive from one year to the next compared to Low Irish ewes (P=0.07). Irish ewes of high maternal genetic merit outperformed their Low counterparts in total number of lambs born and weaned per ewe, but performance did not differ across other traits investigated. This highlights the importance of continuous development of the Irish maternal sheep index to ensure favourable improvements in reproductive, lambing and productivity traits at farm level. Overall, results demonstrate the suitability of NZ genetics in an Irish production system.


Sign in / Sign up

Export Citation Format

Share Document