The use of fixed time artificial insemination programmes for the use of sexed semen in block calving dairy heifers

Livestock ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 124-130
Author(s):  
Mike Kerby ◽  
Tom Clarke ◽  
Tom Angel ◽  
Kythé Mackenzie
Keyword(s):  
Artificial Insemination ◽  
Prostaglandin F2α ◽  
Cost Benefit ◽  
Fixed Time ◽  
Reproductive Efficiency ◽  
Costs And Benefits ◽  
Dairy Heifers ◽  
Conception Rates ◽  
Sexed Semen

In seasonal block calving herds reproductive efficiency can have a significant impact on productivity and profitability. Within this it is key that the nulliparous heifers calve down promptly in the block, and if these heifers can have heifer calves it will expediate genetic gain. There is extensive research into the conception rates of differing protocols and the literature is reviewed to support the choice of protocol used in the subsequent case study. The case study uses a 6-day progesterone protocol with two injections of prostaglandin F2α and sexed semen; it demonstrated acceptable conception rates as well as the variability that can occur between different bulls' semen straws. Finally, the case study assesses the costs and benefits of the synchronisation programme and concludes a cost benefit of £88.55 per heifer.

PSI-7 Comparison of 6-day versus 7-day CIDR protocol with GnRH and PGFα to synchronize crossbred beef cows for fixed-timed ai with sexed semen at two different times

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 281-282
Author(s):  
Nicole N Noga ◽  
Jeremy G Powell ◽  
Brittni P Littlejohn ◽  
Whitney L Rook ◽  
Martin Mussard ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Chi Square ◽  
Treatment Groups ◽  
Conception Rates ◽  
Sexed Semen ◽  
Chi Square Analysis

Abstract Preliminary data indicate that shortening the progesterone exposure with CIDR can improve conception rates compared to the established 7-day CO-Synch protocols. The objective was to determine the effects of shortening progesterone exposure from 7 days to 6 days among crossbred beef cows and fixed-time artificial insemination (FTAI) with sex-sorted semen. A total of 147 fall calving (September-November) crossbred beef cows from one location were randomized to one of four treatments: 1 and 4) 7-d CO-Synch + CIDR protocol with administration of gonadotropin-releasing hormone (GnRH) and a CIDR insert on day 0, prostaglandin F2α (PGF) at CIDR removal on day 7, and FTAI occurring 66 h (Treatment 1) or 74 h (Treatment 4) later; 2 and 3) 6-d CO-Synch + CIDR protocol with administration of GnRH and CIDR insert on day 0, prostaglandin F2α (PGF) at CIDR removal on day 6, and FTAI occurring 72 h (Treatment 2) or 80 h (Treatment 3) later. Sex-sorted semen from Angus sires was used for AI. Pregnancy was determined by ultrasound 40 days after AI. Pregnancy rate was analyzed using the MIXED procedure of SAS with CIDR and AI service time as fixed effects. Chi-square analysis was used to assess the number of pregnant and open cows in each treatment using the FREQ procedure of SAS. There was no difference (P = 0.78) in pregnancy rates between 6-d CIDR (0.59 ± 0.05%) and 7 d CIDR (0.57 ± 0.05%) protocols. Cattle bred a shorter period after CIDR removal (0.64 ± 0.05%) had numerically (P = 0.11) greater pregnancy rates compared to those with a longer period after CIDR removal (0.51 ± 0.05%). There was no difference in the number of pregnant and open cows between treatment groups. These data suggest that using a 6-day or 7-day protocol, regardless of breeding time, results in similar conception rates.

scholarly journals Effects on Synchronization and Reproductive Efficiency of Delaying the Removal of the Intravaginal Progesterone Device by 24 h in the 5d Co-synch Protocol in Heifers

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 849
Author(s):  
Aitor Fernandez-Novo ◽  
Sergio Santos-Lopez ◽  
Jose Luis Pesantez-Pacheco ◽  
Natividad Pérez-Villalobos ◽  
Ana Heras-Molina ◽  
...  
Keyword(s):  
Animal Welfare ◽  
Reproductive Performance ◽  
Artificial Insemination ◽  
Fixed Time ◽  
Reproductive Efficiency ◽  
Beef Heifers ◽  
Animal Management ◽  
Commercial Farms ◽  
Beef Herds ◽  
Farm Economics

In beef herds, increasing animal welfare, improving reproductive performance and easing animal management are key goals in farm economics. We explored whether delaying the removal of the intravaginal progesterone device by 24 h in heifers synchronized with a 5d Co-synch 72-h protocol could improve reproductive efficiency of fixed-time artificial insemination (FTAI). In experiment 1, we examined the total synchronization rate (TSR) in cycling Holstein heifers. Heifers (13.4 ± 0.69 mo.) were randomly assigned to the standard 5d Co-synch 56-h protocol (5dCo56; n = 10), 5d Co-synch 72-h (5dCo72; n = 17), or the modified 5d Co-synch 72-h protocol, in which removal of the progesterone device was delayed by 24 h (6dCo48; n = 19). In experiment 2, 309 cycling beef heifers on 18 commercial farms were subjected to the 5d Co-synch 72-h or 6-d Co-synch 48-h protocol and conception rate (CR) studied. In experiment 1, the three protocols led no differences on TSRs of 80.0% (5dCo56), 88.2% (5dCo72), and 89.5% (6dCo48). In experiment 2, the CR from the beef heifers, observed during two consecutive reproductive seasons did not differ: 59.7% for 5dCo72 and 62.0% for 6dCo48 (p = 0.907). Therefore, delaying removal by 24 h provides satisfactory results without reducing reproductive efficiency of heifers.

Cooled semen for fixed-time artificial insemination in beef cattle

2016 ◽  
Vol 28 (7) ◽  
pp. 1004 ◽  
Author(s):  
Juliana C. Borges-Silva ◽  
Márcio R. Silva ◽  
Daniel B. Marinho ◽  
Eriklis Nogueira ◽  
Deiler C. Sampaio ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Sperm Motility ◽  
Artificial Insemination ◽  
Egg Yolk ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Reproductive Efficiency ◽  
Sperm Abnormalities ◽  
Hypoosmotic Swelling Test ◽  
Interesting Approach

This study evaluated the use of cooled semen in a fixed-time artificial insemination (FTAI) program compared with frozen–thawed semen to improve pregnancy rates in beef cattle. Ejaculates of three bulls were collected and divided into two treatments: (1) frozen–thawed semen and (2) cooled semen. Egg-yolk extender without glycerol was used for the cooled semen treatment. Straws (25 × 106 spermatozoa) were submitted to cooling for preservation at 5°C for 24 h, after which FTAI was performed. Nelore cows (n = 838) submitted to FTAI were randomly inseminated using frozen–thawed semen or cooled semen. There was a 20% increase in the pregnancy per AI (P AI–1) using cooled semen compared with frozen–thawed semen (59.9 ± 4.7 vs 49.4 ± 5.0%; P < 0.005). There was no difference in P AI–1 among the bulls (P = 0.40). The frozen–thawed semen had fewer functional spermatozoa than did the cooled semen when evaluated by sperm motility (61.7 vs 81.0%), slow thermoresistance test (41.7 vs 66.7%) and hypoosmotic swelling test (38.3 vs 53.7%; P < 0.05). The percentage of sperm abnormalities did not differ between the freeze–thawing and cooling processes (18.6 vs 22.1%; P > 0.05). Because there was less damage to spermatozoa and improvement in P AI–1, the use of cooled semen instead of frozen–thawed semen is an interesting approach to increase reproductive efficiency in cattle submitted to a FTAI protocol.

Estrous synchronization and fertility of cross-bred dairy cows using prostaglandin F2α and gonadotropin releasing hormone

2021 ◽  
pp. 171-175
Author(s):  
Abubakr O. Ismail ◽  
◽  
Erneo B. Ochi ◽  
Ambrose S. Jubara ◽  
Bakri Ahmed A/Rahim ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Artificial Insemination ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Releasing Hormone ◽  
Treatment Groups ◽  
Estrous Synchronization ◽  
Descriptive Statistical Analysis

A comparative hormonal study of prostaglandin, gonadotropin releasing hormone and their combination was conducted on 30 randomly selected cross-bred dairy cows of SEMEX project for artificial insemination in Hillat Kuku, Khartoum North, Sudan. The study attempts to determine the response of the animals to hormonal induction and synchronization of estrous as well as fertility following fixed time artificial insemination. Three treatment groups of 10 cows each were undertaken. Groups 1, 2 and 3 involved administration of prostaglandin F2α (PGF2α), gonadotropin releasing hormone (GnRH) and a combination of PGF2α + GnRH, respectively. Descriptive statistical analysis was performed. The results revealed that all the three protocols induced and synchronized estrous were almost synchronous in all the treated groups. However, protocol 3 revealed a significantly (p<0.05) better result of 70% pregnancy rate compared to other two protocols that equally provided 50% pregnancy rates. The study resolves that protocol 3 be highly recommended to change the mindset of farmers about the spread of reproductive technology in Sudan. Protocols 1 and 2 provided acceptable pregnancy rates that can be enhanced with the improvement of management.

8 EFFECT OF SEMEN TYPES (SEXED v. NONSEXED) ON CONCEPTION RATES OF GIROLANDO HEIFERS INSEMINATED IN FIXED-TIME AI

2010 ◽  
Vol 22 (1) ◽  
pp. 162
Author(s):  
J. Almeida ◽  
O. A. Resende ◽  
D. L. Silveira
Keyword(s):  
Body Condition Score ◽  
Fixed Time ◽  
Estradiol Benzoate ◽  
Sao Paulo ◽  
São Paulo ◽  
Device Removal ◽  
Conception Rates ◽  
Sexed Semen ◽  
Condition Score ◽  
Intravaginal Device

With the goal of optimizing protocols, fixed-time artificial insemination (FTAI) was performed under field conditions in a study to evaluate conception rates in Girolando (5/8) heifers (18 to 24 months of age) treated with estradiol benzoate (BE) to induce ovulation. Forty heifers were allocated to 2 groups with 20 animals each: GI-sexed semen (2 million spermatozoa/dose) and GII-nonsexed semen (20 million spermatozoa/dose), with body condition score (BCS) of 3.0 ± 0.14 (scale of 1 to 5), middleweight of 335 ± 38 kg, so that it was made for reutilization of progesterone device. On Day 0 (morning), the animals received 2.0 mg of BE (RIC-BE®,Tecnopec, São Paulo, Brazil), 0.075 mg of D-cloprostenol (Prolise®, ARSA S.R.L., Buenos Aires, Argentina), and an intravaginal device of 1 g of progesterone (Primer®, Tecnopec). On Day 8 (morning) the device was removed and 0.075 mg of D-cloprostenol was managed in the GI animals, then these animals received 1.0 mg of BE 24 h after device removal. The insemination was in the late afternoon of Day 10 with a 6-hour delay (4 to 6 pm). The GII animals received Primer previously used for 8 days (being used in the GI animals under the same protocol). After pregnancy diagnosis at 60 days, a third group was created (GIII) using the not-pregnant animals of GI and GII. In GIII, Primer from third use [disinfected in solution Kilol®-L 1:250 (Quinabra, São Paulo, Brazil) and rinsed with water, dried, and packed in plastic sacks and kept for 60 days] was used following the GI protocol with sexed semen. There were no significant differences (P > 0.05) in the conception rates of 40, 58, and 65% among groups GI (8/20), GII (11/20), and GIII (13/20). These results indicate very good conception rates for heifers, contrary to recommendations of commercial companies of sexed semen that alert for the conception rate for mated animals to be lower when using FTAI and mating protocols in mass, compared with that of AI after estrus observation.

169 Comparison of pregnancy outcomes in dairy heifers artificially inseminated with sexed semen deposited in the uterine horns versus the uterine body

2020 ◽  
Vol 32 (2) ◽  
pp. 211
Author(s):  
S. Kirks ◽  
R. Palomares ◽  
P. Melendez ◽  
M. Ferrer ◽  
A. Hoyos ◽  
...  
Keyword(s):  
Cell Damage ◽  
Animal Health ◽  
Genetic Selection ◽  
Prostaglandin F2α ◽  
Freezing Process ◽  
Dairy Heifers ◽  
Normal Ranges ◽  
Sexed Semen ◽  
On Farm ◽  
Uterine Body

The use of sexed semen (SS) for AI of cattle has resulted in lower pregnancy per timed AI (P/TAI) compared with conventional semen. This has been attributed to lower sperm dose and cell damage during the cell sorting-freezing process. Horn AI is a common practice in equines and canines to improve pregnancy rate when using low sperm doses. The objective was to compare P/TAI and pregnancy loss (PL) in dairy heifers inseminated with SS deposited in the uterine horn (UH) ipsilateral to the ovary containing the preovulatory follicle (POF) versus TAI in the uterine body (UB). This study was performed on two dairy farms in Georgia (A and B). On farm A, 74 Holstein heifers (12 months old) received a 5-day Cosynch + controlled internal drug release (CIDR) protocol including an intravaginal insert (Eazi-Breed CIDR, Zoetis Animal Health) containing 1.38g of progesterone for 5 days and a dose of gonadotrophin-releasing hormone (GnRH) intramuscularly (100µg, 2mL of Factrel, Zoetis Animal Health). At CIDR removal, heifers received a dose of prostaglandin F2α (PGF2α) intramuscularly (25mg, 5mL of Lutalyse, Zoetis Animal Health) and again 24h later; 72h after CIDR removal, heifers received 100µg of GnRH intramuscularly and TAI with frozen-thawed SS. On farm B, 237 Holstein×Jersey heifers (12 months old) received a modified 5-day Cosynch + CIDR. This protocol was similar to that on farm A but did not include GnRH at the time of CIDR insertion or a second dose of PGF2α 24h after CIDR removal. Immediately before TAI, heifers were examined using transrectal ultrasonography (TRUS) to determine on which ovary the POF was present. Each heifer was randomly assigned to TAI using SS in either the UH ipsilateral to the ovary containing the POF (n=150; farm A, n=32; farm B, n=118) or the UB regardless of where the POF was identified (n=161; farm A, n=42; farm B, n=119). Pregnancy was diagnosed 32 days after TAI using TRUS to determine P/TAI. Heifers diagnosed pregnant were re-examined using TRUS at 60 days of gestation to assess PL. Data were analysed using PROC LOGISTIC and the chi-square test of SAS (SAS Institute Inc.). Heifers that received SS in the UH had adequate P/TAI (50.6% (76/150); farm A: 50.0% (16/32); farm B: 50.8% (60/118)), which tended to be numerically greater (P=0.12) than that observed in heifers receiving SS in the UB (43.4% (70/161); farm A: 40.5% (17/42); farm B: 44.5% (53/119)). In addition, PL was not different between groups and was within normal ranges for dairy heifers (10.0 and 9.4% for UH and UB, respectively). In conclusion, TAI of dairy heifers with SS deposited in the UH ipsilateral to the ovary containing the POF resulted in adequate P/TAI, which was 7.2% greater than TAI in the UB. Horn AI with SS might become a valuable tool for optimising reproductive efficiency and genetic selection of dairy herds.

Effect of type of intravaginal progestagen on the outcome of fixed-time artificial insemination

1981 ◽  
Vol 96 (1) ◽  
pp. 243-245 ◽  
Author(s):  
P. A. Smith ◽  
M. P. Boland ◽  
I. Gordon
Keyword(s):  
Artificial Insemination ◽  
Present Experiment ◽  
Fixed Time ◽  
Field Trials ◽  
Oestrous Cycle ◽  
Conception Rates ◽  
Natural Service ◽  
Dose Levels ◽  
Pregnant Mare Serum Gonadotrophin

It is now possible to synchronize the cycle of ewes at all times of the year (Gordon, 1975). Conception rates approaching those obtained following natural service have been reported following double (Colas & Brice, 1970; Colas et al. 1973; Barlow, Pryce-Jones & Reed, 1974; Gordon, 1975) or single (Smith, Boland & Gordon, 1978) set-time inseminations. In France, synchronization of ewes' oestrous cycle is based on the use of a Cronolone pessary (Colas, 1975), while field trials conducted in Britain have used the 60 mg Medroxy progesterone acetate (MAP) sponge (Barlow et al. 1974). Robinson et al. (1967) in an evaluation of different progestagen treatments found MAP to be less predictable than Cronolone. The purpose of the present experiment therefore was to evaluate the use of a 30 mg Cronolone or a 60 mg MAP intravaginal treatment when used in conjunction with fixed-time inseminations. In addition, two dose levels of pregnant mare serum gonadotrophin (PMSG) were compared.

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