scholarly journals 212 Ovarian ultrasound of sows by parity and season to determine effects of induced ovulation and single PCAI on farrowing rate and litter size

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 123-123
Author(s):  
Lidia S Arend ◽  
Robert V Knox ◽  
Amanda M Minton ◽  
Clint R Schwab ◽  
Caleb M Shull ◽  
...  

Abstract Increasing the distribution of semen from genetically superior sires accelerates the rate of improvement of economically important traits. Using a single fixed time post-cervical AI (SFTI) with ovulation control, the number of inseminations per ejaculate can be doubled. The objective of the study was to determine whether ovarian ultrasound could help identify parity (P1, 2, 3-6, ≥ 7) and seasonal (May-Jun, Jul-Aug, Sep-Oct) effects on fertility following induced ovulation and SFTI. Sows received OvuGel® (n = 914) on Days 3-5 after weaning and a SFTI 24 h later. Control sows (n = 881) that expressed estrus on Days 3-6 received a post-cervical AI on each day standing. Ovaries of a sub-population of sows (n = 436) were scanned by ultrasound to assess follicle size and insemination to ovulation interval. Interval from insemination to ovulation > 24 h tended (P = 0.09) to reduce farrowing rate (FR, 74.1 ± 2.8%) compared to inseminations £ 24 h (83.4 ± 2.8%), regardless of treatment. In addition, sows that ovulated by Day 6 after weaning had greater (P = 0.03) total born (TB, 12.9 ± 0.5) than those ovulating ≥ 7 d (11.5 ± 0.5). Follicle number (16.3 ± 0.7) and size (7.0 ± 0.5 mm) on Day 4 did not differ between treatments. OvuGel increased (P = 0.002) the proportion of sows ovulating (88.9%) versus Controls (78.6%), but for both treatments, fewer P1 sows ovulated (75.0%) when compared to P3-6 (90.4%). Treatments did not differ in FR (78.5%), but seasonal interactions were observed (P = 0.05), most notably in Sep-Oct. Parity affected FR (P = 0.02), and was lower in P1 (66.1%) compared to 3 P2 (82.2%). Also, OvuGel and Control did not differ in TB (13.0) but parity ≥ 7 had the lowest TB (11.8) compared to younger parity females. In summary, OvuGel increased the proportion of sows ovulating by 10.3%, resulting in similar FR and TB compared to Control sows inseminated multiple times based on estrus.

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 12-12
Author(s):  
Robert V Knox ◽  
Ashley Daniel ◽  
Jenny Patterson ◽  
Lidia S Arend ◽  
George Foxcroft

Abstract In experiment 1, prepubertal gilts with (n = 264) and without (n = 43) birth records received Fenceline (FBE) or Physical (PBE) Boar Exposure (BE) in a Boar Exposure Area (BEAR). At 185 d of age, gilts (13/pen) received BE for 15 min/d for 3 wk. At the start of Week 3, anestrual gilts received PG600 or no-PG600 (Control). At estrus, females were moved into stalls and inseminated at 2nd heat. Gilts born in larger litters were lighter (r = -0.26) while heavier pigs grew faster to puberty (r = 0.25). PBE increased estrus in Week 1 (38%) over FBE (28%). In Week 3, PBE-PG600 increased estrus (79.9%) compared with PBE- Control (36.2%), while FBE-PG600 and Control did not differ (52.7 vs. 42.5%). By 6 wk, estrus tended to be greater (P < 0.08) for PBE (91.2%) than FBE (83.2%). Reduced fertility associated with: 1) small birth litter; 2) heaviest birthweight; 3) slower growth rate; 4) delayed puberty and age at 1st service; and 5) abnormal estrus interval. Experiment 2 tested the pubertal response to PBE or FBE with 10 or 20 gilts/pen. Gilts (n = 180) at 168 d with 1.8 m2 floor space received BE once/d for 15 min for 1–3 wk. At the start of Week 3, anestrual gilts received PG600. Estrus in Week 1 (7.3%) did not differ, but a BE x Pen effect occurred in Week 2 (estrus range: 15–34%). In Week 3, PG600 increased estrus (P < 0.03) in Pens of 10 (83.7%) compared to Pens of 20 (64.1%). BE method had no effect and Pens of 10 had greater estrus (P = 0.05) than Pens of 20 (88.3 vs 75.8%). These results indicated that use of PBE, a BEAR, smaller group size, and PG600 can be used in combinations to enhance puberty induction. Birth and pubertal measures influenced service and farrowing rate, litter size, and age at removal.


2018 ◽  
Vol 58 (11) ◽  
pp. 2029 ◽  
Author(s):  
F. De Rensis ◽  
C. Mazzoni ◽  
R. Saleri ◽  
A. Scollo ◽  
K. J. Plush ◽  
...  

The objective of the present study was to compare two common durations of altrenogest (ALT) feeding during different periods of the year on the fertility of gilts after ALT withdrawal. During a 12-month period gilt replacements that were assumed to be cyclic were subjected to oestrus synchronisation with 15 mg/day ALT administered for 18 days (ALT-18; n = 268) or 14 days (ALT-14; n = 153) whereas 275 non-treated gilts served as controls. Fewer ALT-14 than ALT-18 gilts expressed oestrus by 7 days after last ALT treatment (79.1% vs 88.8%; P < 0.05). Farrowing rate was lower (P < 0.05) for ALT-14 than for the other groups (81%, 91% and 92% for ALT-14, ALT-18, and Control, respectively) but farrowing rates were not affected by time of year. Control litter sizes were not different from ALT-14 except during September to November when Control litter sizes were larger than either ALT treatments (13.6 ± 0.33, 12.3 ± 0.65 and 12.7 ± 0.39 for Control, ALT-14 and ALT-18, respectively; P < 0.05). The ALT-18 gilts had larger litter sizes during January to August. The present data suggest that the appropriate duration of ALT feeding to synchronise oestrus in gilts is 18 days.


2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 111-111
Author(s):  
Kara R Stewart ◽  
Brad Belstra ◽  
Kilby L Willenburg ◽  
Domingo Gómez-López ◽  
Robert V Knox

Abstract Induced ovulation with single fixed time artificial insemination (SFTAI), combined with uterine (IUI) or deep uterine insemination (DUI), could improve fertility with low numbers of sperm and allow greater use of high genetic merit boars. At weaning (0 h), sows (n = 534) were assigned by parity and estrus induction method (eCG or Control) to receive 1200 × 106 sperm by IUI, 600, 300, or 150 × 106 sperm by IUI or DUI, or 75 × 106 sperm by DUI. At 80 h post weaning, sows received OvuGel and 26 h later a pooled semen SFTAI. Ultrasound was performed to determine follicle size and time of ovulation (OV). Sows were slaughtered 27 d after AI to determine pregnancy and litter traits. There was no effect (P &gt; 0.05) of eCG on estrus (93%) within 5 d of weaning or follicle size (6.1 mm) at OvuGel, but wean-to-estrus (3.8 vs. 4.0 d,P &lt; 0.01) and AI-to-OV (15.9 vs. 17.0 h, P = 0.04) intervals and AI-to OV were slightly reduced. eCG did not affect pregnancy rate (78.6%), number of CL (21.7), or number of viable embryos (12.2). There was no effect of number of sperm or site of insemination (P &gt; 0.05) on pregnancy rate (range: 80.9% to 70.5%), but AI occurring after ovulation reduced pregnancy rate (P &lt; 0.02). Total number of embryos (range: 16.5 to 10.3) increased with CL number (P &lt; 0.001) but was not affected by number of sperm or site of insemination (P &gt; 0.05). Higher sperm treatments (1200 and 600 x 106) had more embryos compared to lower sperm treatments (P &lt; 0.01), suggesting that lower sperm numbers effects litter size more than the pregnancy status. Acceptable fertility can be achieved with low sperm numbers when using SFTAI and uterine deposition, but AI-to-OV interval and ovulation rate influence final fertility.


2020 ◽  
Vol 98 (9) ◽  
Author(s):  
Brad A Belstra ◽  
Kilby L Willenburg ◽  
Domingo H Gómez-López ◽  
Robert V Knox ◽  
Kara R Stewart

Abstract Reducing the number of sperm needed to produce a litter with artificial insemination (AI) allows greater use of higher genetic merit boars. Induced ovulation with single fixed-time artificial insemination (SFTAI), combined with intrauterine (IUI) or deep uterine insemination (DUI), could improve fertility with low numbers of sperm. The objectives of the study were to determine the fertility effects of sperm numbers and the site of insemination. At weaning (0 h), sows (n = 534) were assigned by parity and estrus induction method (equine chorionic gonadotropin [eCG] or Control) to receive 1,200 × 106 sperm by IUI; 600, 300, or 150 × 106 sperm by IUI or DUI; or 75 × 106 sperm by DUI. At 80 h postweaning, sows received OvuGel and 26 h later a SFTAI using pooled semen. Sows were exposed to boars once daily and ultrasound was performed to determine follicle size and time of ovulation. Following SFTAI, sows were slaughtered 27 d after AI to determine pregnancy and litter traits. Data were analyzed using different models to test for effects of estrus induction, interaction of three levels of sperm (600 to 150) with two levels for site (IUI vs. DUI), and the overall effects of AI method (eight treatments). There was no effect (P &gt; 0.05) of estrus induction on estrus (93%) within 5 d of weaning or on follicle size (6.1 mm) at OvuGel, but wean-to-estrus interval (3.8 vs. 4.0 d) was slightly reduced (P &lt; 0.01) as was AI-to-ovulation interval (15.9 vs. 17.0 h, P = 0.04) for eCG and Control, respectively. There was no effect (P &gt; 0.05) of estrus induction on pregnancy rate (78.6%), number of corpora lutea (CL; 21.7), or number of viable embryos (12.2). There was no effect of number of sperm or site of insemination and no interaction (P &gt; 0.05) on pregnancy rate (range: 80.9% to 70.5%), but AI occurring after ovulation reduced the pregnancy rate (P &lt; 0.02). The total number of embryos (range: 16.5 to 10.3) was not affected by estrus induction, number of sperm, or site of insemination (P &gt; 0.05), but was influenced by AI treatment (P &lt; 0.01). Treatments with a higher number of sperm (1,200 and 600) had more embryos compared with those with a lower number of sperm (300 to 75). The numbers of embryos also increased with the number of CL (P &lt; 0.0001). These results suggest that the lower number of sperm affects litter size more than the pregnancy status. Acceptable fertility can be achieved with low numbers of sperm when using a SFTAI and uterine deposition, but AI-to-ovulation interval and ovulation rate influence final fecundity.


2010 ◽  
Vol 50 (7) ◽  
pp. 670
Author(s):  
Daniel Cavestany ◽  
Daniela Crespi ◽  
Alvaro Fernandez

To compare two oestrus synchronisation protocols in beef heifers presynchronised with two prostaglandin F2α (PG) treatments, 36 h after the second PG treatment one group (hCG-OB group; n = 112) received 250 IU of hCG and 0.5 mg of oestradiol benzoate (OB) followed by fixed time artificial insemination (FTAI) 30 h later. Additional oestrus detection (OD) and artificial insemination (AI) was done in this group for 3 days after FTAI; heifers rebred during this period were considered open to the FTAI. The Control group (n = 112) received only OD and AI for 6 days after the second PG treatment. Follicular size was measured at the time of AI in a subsample of heifers (59 in the hCG-OB group and 34 in the Control group). Results were evaluated separately either considering heifers pregnant at FTAI or those pregnant at FTAI + 3-day OD + AI. The FTAI conception rate was 45.5 vs 76.5% for the Control group (P < 0.0001) and pregnancy rates were 45.5 and 67.0% (P = 0.0014); FTAI + OD + AI conception rates were 63.4 and 76.2% (P = 0.0404) and pregnancy rates 63.4 and 62.8% (P = 0.5719) (hCG-OB and Control groups, respectively). There was a significant correlation (r = 0.713, P < 0.01) between follicle size at FTAI and pregnancy in the hCG-OB group, but not in the Control group (r = 0.3465, P > 0.1). In conclusion, acceptable synchronised conception rate and pregnancy rate were obtained by using this protocol, and the results were improved by complementing it with OD + AI for 3 days after FTAI.


Author(s):  
J. P. Lakher ◽  
M. K. Awasthi ◽  
J. R. Khan ◽  
M. R. Poyam

The present study was conducted to investigate the efficacy of Ovsynch and Ovsynch plus protocol in postpartum (day 60) Sahiwal cows (n=18). Animals were randomly divided into three equal groups, viz., Ovsynch group Ovsynch plus group and Control group. Animals of group I (n = 6) were treated with traditional Ovsynch protocol. The animals (n = 6) of group II were treated with Ovsynch plus protocol which consisted of an initial intramuscular injection of eCG (Folligon) @ 250 IU on day 60 postpartum followed 3 days later by GPG (Ovsynch) protocol. In group-III Control, no treatment was given to animals (n = 6). Treated animals were inseminated at a fixed time between 14 and 20 hrs after second GnRH injection, irrespective of estrus detection. Blood samples were collected from each animal on days 50 and 60 postpartum to determine the status of cyclicity in animals based on serum concentrations of progesterone (P4). A third blood sample was collected on the day of prostaglandin treatment to determine the response of first GnRH injection. Four animals each were cyclic, and two were acyclic in both treatment groups. Four animals each responded to first GnRH treatment in both treatment groups. Similarly, two animals each got conceived giving conception rate of 50% (2/4) in each treatment. In the control group, one out of 6 animals got conceived yielding 16.66 % conception rate (1/6) during the study period. It may be thus concluded that Ovsynch and Ovsynch plus protocol may be used during the early postpartum period to improve the reproductive efficiency in postpartum Sahiwal cows.


1999 ◽  
Vol 1999 ◽  
pp. 176-176
Author(s):  
A.R. Peters ◽  
L.A. Dwyer ◽  
A. Dawson ◽  
P.A. Canham ◽  
J.D. Mackinnon

The problem of seasonal infertility in pigs has been recognised for many years. The infertility complex can may be manifested by increased returns to service, prolonged weaning to oestrus intervals and decreased litter size. The purpose of this trial was to evaluate the effects of Buserelin treatment on fertility in sows and gilts during the seasonally infertile period.A total of 1231 mixed parity sows and gilts from five outdoor herds in East Anglia were randomly assigned to one of three treatment groups. Any sows not presented for service at first post weaning oestrus were excluded. All sows and gilts judged to be in adequate health and condition to be kept in a commercial breeding herd were included. Group C sows and gilts were given no treatment. Group R1 sows and gilts were injected i.m. with 8μg Buserelin (2.0ml Receptal; Hoechst Roussel Vet UK Ltd) on the day of service.


2021 ◽  
Vol 10 (13) ◽  
pp. 2757
Author(s):  
Xia Hao ◽  
Amandine Anastácio ◽  
Kenny A. Rodriguez-Wallberg

Fertility preservation through ovarian stimulation, aiming at cryopreserving mature oocytes or embryos, is sometimes unsuccessful. This clinical situation deserves novel approaches to overcome infertility following cancer treatment in patients facing highly gonadotoxic treatment. In this controlled experimental study, we investigated the feasibility of in-vitro culturing secondary follicles isolated from superovulated ovaries of mice recently treated with gonadotropins. The follicle yields of superovulated ovaries were 45.9% less than in unstimulated controls. Follicles from superovulated ovaries showed faster growth pace during the initial 7 days of culture and secreted more 17β-estradiol by the end of culture vs controls. Parameters reflecting the outcome of follicular development and oocyte maturation competence in vitro were similar between superovulated and control groups, with a similar follicle size at the end of culture and around 70% survival. Nearly half of cultured follicles met the criteria for in-vitro maturation in both groups and approximately 60% of those achieved a mature MII oocyte, similarly in both groups. Over 60% of obtained MII oocytes displayed normal-looking spindle and chromosome configurations, without significant differences between the groups. Using a validated follicle culture system, we demonstrated the feasibility of secondary follicle isolation, in-vitro culture and oocyte maturation with normal spindle and chromosome configurations obtained from superovulated mice ovaries.


Author(s):  
Tshepo Teele

Background: This study aimed to investigate the influences of sexual preparation on the effects of boars’ semen viability on the fertilization capacity of artificially inseminated sows. After all, boar sires more pigs than farrowed by a sow which the boar has been mated to improve reproductive parameters in response to AI. Methods: The semen viability of boars were studied during various sexual stimulations and analyzed during the study period. Sperm rich fractions were collected and separated at every level of sexual stimulation during the morning (08:30) and the afternoon (14:30) hours, respectively. Artificial insemination was performed following three levels of sexual preparations of boars (0 minutes of sexual restraint (MSR), 5 MSR and 10 MSR) before semen collection. Receptive sows were inseminated and evaluated for fertility traits using non-return rate, farrowing rate and litter size. Result: The non-return rate was recorded as a percentage of sows conceived after insemination over the total number of sows inseminated. The farrowing rate was recorded as a percentage of sows that farrows over the number of sows conceived and litter size as several live piglets per sow. Sexual desire was influenced by sexual preparations and significantly influenced the fertility of the artificially inseminated sows. This study is of practical significance to the animal breeder mainly because boars have greater influence than sows on the average litter size and live piglets. The study concludes that the use of at least 5 to 10 minutes of sexual restraint during the afternoon periods prior to semen collection and artificial insemination is found to be a practical method for optimizing sperm viability and fertility of sows in the intensive system.


Author(s):  
Fei Ma ◽  
Yunjie Wu ◽  
Siqi Wang ◽  
Xiaofei Yang ◽  
Yueyang Hua

This paper presents an adaptive fixed-time guidance law for the three-dimensional interception guidance problem with impact angle constraints and control input saturation against a maneuvering target. First, a coupled guidance model formulated by the relative motion equation is established. On this basis, a fixed-time disturbance observer is employed to estimate the lumped disturbances. With the help of this estimation technique, the adaptive fixed-time sliding mode guidance law is designed to accomplish accurate interception. The stability of the closed-loop guidance system is proven by the Lyapunov method. Simulation results of different scenarios are executed to validate the effectiveness and superiority of the proposed guidance law.


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