Follicular Dynamics,Interval to Ovulation and Fertility After AI in Short‐Term Progesterone and PGF2α Oestrous Synchronization Protocol in Sheep     

JF Cox  R Allende  E Lara  A Leiva  T Díaz  J Dorado  F Saravia 《Reproduction in domestic animals》2012,47(6):946-951

The study was aimed to assess the influence that short‐term progesterone treatments have on follicular dynamics, oestrus and ovulation in sheep. The treatment was tested thereafter in a field trial to assess its fertility after AI with fresh semen. In a first experiment, 12 ewes without CL were grouped to receive a new (n = 6) or used CIDR (n = 6) for 7 days and blood samples were obtained to follow plasma progesterone profiles. In a second experiment, 39 cycling ewes were synchronized by a 7‐day P4+PGF2α protocol using a new (n = 20) or a 7‐day used CIDR (n = 19). Half of both groups received 400 IU eCG and half remained untreated as controls. Ultrasound ovarian examination and oestrous detection were used to compare follicular dynamics, oestrus and ovulation in both groups. In a third experiment, 288 ewes in 3 farms were synchronized by the short‐term P4+PGF2α+eCG protocol and ewes were AI with fresh semen 24 h after oestrous detection. Lambing performance was used to test the fertility of the treatment. In Experiment 1, ewes with new inserts presented higher P4 concentration than ewes with used inserts throughout the sampling period (p < 0.05) and exhibited a P4 peak at days 1‐2 of the treatment that was not observed in ewes with used inserts. In Experiment 2, ewes treated with new and used inserts show similar ovarian and behavioral traits (p > 0.10). However, ewes treated with eCG show shorter interval to oestrus (p = 0.004) and tend to have larger mature CL (p = 0.06). In Experiment 3, oestrous presentation and lambing performance after AI with fresh semen was considered normal compared to published results. Results suggest that the oestrous synchronization protocol based on P4+PGF2α allows little control of follicular dynamics without compromising fertility after AI with fresh semen provided that eCG is added at the end of the treatment.  相似文献   

Administration of hCG 5 days after Breeding and Reproductive Performance in Nulliparous Dairy Goats     

JF Fonseca  CAA Torres 《Reproduction in domestic animals》2005,40(6):495-499

The objective of this study was to investigate the effect of hCG administration 5 days after breeding on plasma progesterone (P4) concentration and reproductive performance of oestrous-induced nulliparous dairy goats. A total of 59 nulliparous goats (36 Alpine and 23 Saanen) received intravaginal sponges with 60 mg medroxyprogesterone acetate for 9 days plus 200 IU equine chorionic gonadotrophin (eCG) and 22.5 microg d-cloprostenol 24 h before sponge removal. After detection of oestrus (day of oestrus = day 0) and breeding, 49 females were randomly assigned, according to the breed, into two treatments (T1 and T2). In T1 (n = 25) and T2 (n = 24), animals received intramuscular injection of 1 ml of saline solution (control) or 250 IU hCG, respectively, 5 days after breeding. Plasma P4 concentration (ng/ml) was determined from blood sampled on days 0, 5, 7, 13, 17, 21, 28 and 45 after breeding. Animals were scanned by transrectal ultrasound (5 MHz probe) on days 35 and 70 after breeding for detection of pregnancy. Plasma P4 concentration did not differ (p > 0.05) between treatments in all days, but it was increased (p < 0.05) in Saanen than in Alpine goats from days 13 to 45. Pregnancy and parturition rates, litter size and gestation period were similar (p > 0.05) to treatments and breeds. Results of this study indicate that human chorionic gonadotrophin (hCG) administration 5 days after breeding did not significantly alter reproductive performance in dairy nulliparous goats and that plasma P4 differed between Saanen and Alpine goats.  相似文献   

Ivermectin toxicosis in a neonatal foal   总被引：1，自引：0，他引：1  

LM GODBER †  FJ DERKSEN  JF WILLIAMS†  B. MAHMOUD§ 《Australian veterinary journal》1995,72(5):191-192

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Colour‐Doppler ultrasound imaging as a laparoscopy substitute to count corpora lutea in superovulated sheep          下载免费PDF全文

PHN Pinto  GM Bragança  MFA Balaro  EKN Arashiro  GB dos Santos  GN de Souza  JMG Souza‐Fabjan  JF Da Fonseca  FZ Brandão 《Reproduction in domestic animals》2018,53(1):266-269

This study evaluated colour‐Doppler ultrasound imaging (UI) as a substitute for laparoscopy to count the corpora lutea (CL) in superovulated sheep. Twenty‐five Santa Ines ewes were superovulated three times at 21‐day intervals. Corpora lutea were counted by colour‐Doppler UI (CL_DOPPLER) 6 days after each superovulation and confirmed by laparoscopy (CL_LAP) 12 hr later. The mean number of CL was similar for both techniques (2.1 ± 2.5 vs. 2.1 ± 2.7 for CL_DOPPLER and CL_LAP, respectively) with a significant positive correlation (r = .94; r²=.89). Colour‐Doppler UI effectively evaluated the ovarian response in superovulated ewes and efficiently identified animals that did not respond to superovulation.  相似文献   

Elimination of bovine viral diarrhoea virus in New Zealand: a review of research progress and future directions     

J-H Han  AM Weir  JF Weston  C Heuer  MC Gates 《New Zealand veterinary journal》2018,66(6):273-280

The major impacts of bovine viral diarrhoea (BVD) on cattle health and production have prompted many countries to embark on national elimination programmes. These programmes typically involve identifying and removing persistently infected (PI) cattle in infected herds and implementing biosecurity measures, such as pre- or post-movement testing. In order to design a systematic national control programme to eliminate BVD in New Zealand, which achieves the greatest benefits to the industries at the lowest cost to individual farmers, an accurate understanding is necessary of the epidemiology, economics and social motivation for BVD control in New Zealand. In this article we briefly review the pathogenesis of BVD, transmission and diagnosis of BVD virus infection, and effectiveness of vaccination. We summarise the current state of knowledge of the prevalence, risk factors for transmission, and financial impacts of BVD in New Zealand. We describe control programmes in Europe and then discuss the challenges that must be addressed to design a cost-effective national control programme to eliminate BVD in New Zealand.  相似文献   

Pre‐Selection Test to Identify High Responder Donor Goats          下载免费PDF全文

MFA Balaro  FZ Brandão  ALRS Maia  JMG Souza‐Fabjan  MI Cueto  AE Gibbons  JF Fonseca 《Reproduction in domestic animals》2016,51(3):386-391

The aim of the study was to evaluate the feasibility of pre‐selection of high or low responder does prior to the superovulatory protocols. Twenty Saanen does received 800 IU of equine chorionic gonadotropin (eCG) at the end of long‐term progestogen treatment. Fourteen days later, a second progestogen protocol associated with a multiple‐dose follicle stimulation hormone (FSH) treatment (5 IU/kg of FSH, in six decreasing doses between days 4 to 6 of the protocol) was administered. Transrectal ultrasound was used to assess the follicular status at the beginning of superovulatory treatments, at the oestrous onset and on the seventh day of the oestrous cycle for counting corpora lutea (CL). A significant lower number of CL was obtained in eCG‐treated in comparision with FSH‐treated does (p < 0.05). A quartic regression was able to explain the relationship between the number of CL in response to both treatments (r²=0.50; p < 0.05). Seventy per cent (14 of 20) of does maintained the same ovulatory response (high or low) after treatments. The Kappa (κ = 0.40; p < 0.05) and Spearman (rs = 0.39; p = 0.08) coefficients were able to show a relationship between treatments. Regarding the follicular status, there is a significant relationship between the number of small follicles (r = 0.71; r²=0.47; p < 0.01) and total follicles (r = 0.60; p < 0.01) at eCG and first FSH dose with the number of CL. Moreover, it was found a negative relationship between the presence of large follicles and the number of CL in response to eCG treatment (r = ?0.44; p < 0.05), but not from FSH (p > 0.05). In conclusion, the screening test with eCG has the potential to identify Saanen does that will better respond to the superovulatory protocol with FSH. In addition, it highlighted the importance of an ultrasound evaluation prior to the beginning of superovulatory treatments with FSH to characterize the follicular status and identify the potential donors of high ovulatory response in MOET programmes in goats.  相似文献   

Assessing whether dairy cow welfare is “better” in pasture-based than in confinement-based management systems     

JF Mee  LA Boyle 《New Zealand veterinary journal》2020,68(3):168-177

ABSTRACT

Consumers perceive pasture-based systems of milk production as natural and therefore better for cow welfare than confinement systems. However both systems are heterogeneous and continually evolving, varying from total confinement to total pasture with many hybrid intermediaries. To compare the welfare of dairy cows in these various systems, we use the three spheres framework, comprising biological functioning, natural behaviour and affective states. Considering biological functioning, pasture-based cows are less at risk of subclinical and clinical mastitis, claw lesions, lameness, metritis, early embryonic mortality, culling and mortality, but at more risk of internal parasitism, malnutrition and delayed onset of oestrous activity postpartum than confined cows. Regarding natural behaviours, pasture-based cows exhibit less agonistic behaviour, better lying behaviour, more normal oestrous behaviours and better synchronicity of behaviours than confined cows. They also have the opportunity to graze, which is one of the main features of the behavioural repertoire of dairy cows, but, they may also experience long periods away from pasture in larger herds, and severe climatic stresses which will become increasingly important as the climate changes. Our current ability to assess the affective state of dairy cows is poor. For example, hunger is an important subjective state that cannot be measured directly. The growing focus on ensuring that animals have lives worth living, means that dairy cows should garner some positive emotions from their lives, and it seems clear that pasture access is essential for this. Clearly measurement of affective state is an important challenge for future dairy cow welfare research. At the extremes of management systems, there can be major differences in animal welfare but in hybrid systems, dairy cows experience elements of both confinement and pasture which may ameliorate the negative effects of each on cow welfare. Ultimately, the optimal system gives cows an element of choice between both environments. Moreover management of the system, whether it is confinement or pastured-based, may be as important as the system of management in ensuring good dairy cow welfare and addressing societal concerns.

Abbreviations: BCS: Body condition score; TMR: Total mixed ration  相似文献   

Assessing the usefulness of B‐mode and colour Doppler sonography,and measurements of circulating progesterone concentrations for determining ovarian responses in superovulated ewes          下载免费PDF全文

MEF Oliveira  IF Ribeiro  MGK Rodriguez  GS Maciel  JF Fonseca  FZ Brandão  PM Bartlewski 《Reproduction in domestic animals》2018,53(3):742-750

The main goal of this study was to assess the usefulness of two imaging modalities, namely the B‐mode and colour Doppler sonography, and serum progesterone (P₄) concentrations for determining the ovarian response in superovulated ewes. Twenty‐four sexually mature Santa Inês ewes underwent the superovulatory treatment consisting of eight injections of porcine FSH (total dose of 200 or 133 or 100 mg; n  =  8 ewes/total dose) given at 12‐hr intervals and initiated 48 hr before CIDR ^® (Pfizer Inc., Auckland, New Zealand) removal. Six days after natural mating, the ovaries of all donor ewes were visualized and examined with transrectal ultrasonography and then with videolaparoscopy to identify and enumerate corpora lutea (CL ) and luteinized unovulated follicles (LUF s). Jugular blood samples were collected just prior to ovarian examinations. The total number of CL (r  =  .78 and 0.83, p  <  .0001) and LUF s (r  =  .74 and 0.90, p  <  .0001) enumerated using the B‐mode and colour Doppler ultrasonographic technique, respectively, were correlated with that ascertained by videolaparoscopy. Circulating concentrations of P₄ were related directly to the number of healthy CL (r  =  .73, p  =  .0002) and inversely to the number of prematurely regressing CL (r  = ?.46, p  =  .03), but the accuracy of predicting the number of short‐lived CL with serum P₄ concentrations was very poor. The present results indicate that ultrasonographic imaging and serum P₄ measurements on the day of embryo recovery are useful indicators of total/normal CL numbers and both ultrasonographic techniques can be used to quantify LUF s in superovulated ewes.  相似文献   

In vitro Fertilizing Capacity of Deep Frozen Boar Semen Packaged in 0.5 and 5 ml Straws     

A Córdova  JF Pérez  B Lleó  C García Artiga  & S Martín Rillo 《Reproduction in domestic animals》2001,36(3-4):199-202

The aim of this study was to evaluate the straw size effect used for freezing on the in vitro fertilizing capacity. Twenty-one ejaculates from seven fertile boars were frozen under controlled conditions in 0.5 and 5 ml straws. Thawed semen was compared to fresh semen. For fresh and thawed semen in 0.5 and 5 ml straws, the results were: 92.18, 77.38 and 79.04% sperm penetration; 80.68, 66.89 and 69.33% monospermy; 11.51, 10.49 and 9.74% polyspermy; 86.19, 47.14 and 47.02% motility and 75.52, 48.19 and 46.81% normal apical ridge (NAR), respectively. Analysis of variance and test of multiple comparisons showed that under the conditions employed, penetration, monospermy, motility and NAR were significantly reduced by freezing–thawing, but polyspermy was much less affected. The results obtained suggest that frozen boar semen is adequate for in vitro fertilization. In addition freezing in 5 ml straws did not have any detrimental effect on either penetration, monospermy, polyspermy, motility and NAR, in comparison with freezing in 0.5 ml straws.  相似文献   

Effect of Different Doses of Prostaglandin on the Area of Corpus Luteum, the Largest Follicle and Progesterone Concentration in the Dairy Cow     

A Répási  JF Beckers  J Sulon  Zs Perényi  J Reiczigel  O Szenci 《Reproduction in domestic animals》2003,38(6):423-428

Lactating dairy cows with a mature corpus luteum (CL) (diameter of ≥17 mm determined by ultrasonography) and having a follicle with a diameter of 10 mm (n = 49) were randomly assigned to three groups. The first group was treated with a single dose of exogenous prostaglandin (25 mg), while the second group was treated with 35 mg on day 0, and the third group served as control in order to evaluate the effect of rectal manipulation on the CL during ultrasonographic examination. Blood samples were collected daily for analysing progesterone (P4) concentrations. In group 1 the incidence of oestrus and artificial insemination (AI) in 10 days after treatment was 95% (19 of 20). The conception rate was 31.6%, and the average time to oestrus after treatment was 3.7 day. In group 2 the incidence of oestrus and A.I. was 84.2% (16/19). The conception rate was 31.2%, and the average time to oestrus after treatment was 2.8 day. In the untreated group only two cows (2/10) exhibited oestrus during the examined period and none of them became pregnant. There were no significant differences between the two treated groups in terms of reduction in the area of CL and P4 concentrations and of an increase in the area of the dominant follicles. At the same time, the decrease in the percentage changes relative to the area of CL and to the concentrations of P4 were statistically significant in both treated groups.  相似文献