Antioxidant capacity, reproductive response and glucose concentration and insulin of ewes supplemented prior to insemination with orange residue

ABSTRACT The objective was to evaluate the antioxidant capacity, glucose and insulin concentration and reproductive performance of ewes supplemented with orange residue prior to insemination. Fifty-five multiparous ewes were divided into two corrals, and 15 unbred ewes were kept individually to measure feed consumption. Two integral diets were administered; T0: control treatment and T1: with 20% of dry matter of orange residue. Ten days after the start of supplementation, the ewes were synchronized. Supplementation was finalized prior to artificial insemination, then, a blood sample was taken to measure the antioxidant capacity and glucose and insulin concentration. An analysis of variance was made to evaluate the effect of treatment on the antioxidant capacity, glucose and insulin; and to analyze the response to estrus, percentage of gestation and prolificity a ji squared test was performed. Of 9 antioxidant compounds found in the orange residue, hesperidin (7.44%), chlorogenic acid (0.50%) and protocatechuic acid had the highest concentration. Feed intake, estrus response, percentage of gestation, antioxidant capacity, and glucose and insulin concentration were not affected by the treatment. It is concluded that inclusion of 20% of orange residue in the diet prior to insemination in ewes is possible.

The effectiveness of prostaglandin nanoparticles in corpus luteum regression

Research examined the formation of prostaglandin nanoparticles and their effect on corpus luteum (CL) regression carried out at IRIAP. The nanoparticles formation was carried out using the ionic gelation method. The nanoparticles have a particle size of 316.80±0.14 nm, polydispersion index of 0,453±0,001, zeta potential of +17,40±0,85 mV with 69,69±8.81% hormone entrapment. The effectiveness of nanoparticle in CL regression was observed (prostaglandin vs prostaglandin nanoparticles) using ultrasound observation, hormone profile and estrus response. Further, the size of the ovulating follicle, the time of ovulation, the size of the CL and the onset of estrus after the administration of the prostaglandins were observed. The observation showed that the intramuscular administration of prostaglandin and prostaglandin nanoparticles did not significantly differ on the onset of estrus, time of ovulation, the ovulating follicle size, size of CL and progesterone concentration. The onset of estrus occurred on 2.50 ± 0.58 and 2.33 ± 0.52 days, the ovulation time after hormone administration was on days 3.50 ± 0.55 and 2.83 ± 0.75 with the ovulation follicle size of 16, 62 ± 0.96 and 17.03 ± 1.13 mm, while the CL measures at H-3 were 13.56 ± 2.28 and 10.45 ± 0.88, the progesterone H-2 concentrations were 0.299 and 0.395, respectively for prostaglandin and prostaglandin nanoparticles. It can be concluded that the formation of nanoparticles did not impair the effectiveness of hormones in CL regression so that it can be used to increase the effectiveness of estrus synchronization

PSV-3 Ovarian dynamics of brahman cows submitted to five-day or twelve-day progesterone-based estrus synchronization protocol

The aim of this study was to investigate the ovarian response of Brahman cows submitted to two different estrus synchronization protocols and to determine the estrus response and ovulation time. A total of 153 Brahman cows were randomly assigned to receive one of the following estrus synchronization protocols: 1) CIDR insert and an injection of prostaglandin F2α (25 mg, PGF) on Day -5 and CIDR removal with PGF on Day 0 (CIDR5; n = 77); 2) CIDR insert on Day -12 and an injection of PGF on Day -12, Day -5 and Day 0 upon CIDR removal (CIDR12; n = 76). Estrotect breeding indicator patches were placed on Day 0 and cows were artificially inseminated (AI) 12h after estrus detection; cows not detected in estrus after 96h received TAI coupled with 100 µg of GnRH. Ovarian dynamics were observed during the protocol and follicular diameter were measured every 12h after AI until ovulation. Cows synchronized with CIDR12 had increased follicular diameter (CIDR5, 10.19 ± 0.51 vs. CIDR12, 13.12 ± 0.52 mm; P = 0.01) and decreased serum concentrations of progesterone (CIDR5, 1.68 ± 0.12 vs. CIDR12, 0.81 ± 0.12 ng/ml; P < 0.01) at CIDR removal. The percentage of cows exhibiting estrus did not differ between treatments (CIDR5, 66.2 vs. CIDR12, 64.5%; P = 0.25). No difference was observed in ovulation rate (CIDR5, 94.1 vs. CIDR12, 94.1%; P = 0.6). Time of estrus expression and ovulation time after CIDR removal did not differ (CIDR5, 59.9 ± 2.3 vs. CIDR12, 61.5 ± 2.3h; P = 0.71 and CIDR5, 88.1 ± 2.6 vs. CIDR12, 90.9 ± 2.6h; P = 0.75; respectively). In conclusion, extended length of CIDR with additional PGF increased follicular diameter and decreased concentrations of progesterone but did not influence estrus response and ovulation time in Brahman cows.

233 Estrus Response and Pregnancy Rates of Beef Replacement Heifers Enrolled in Two Fixed-time Artificial Insemination Protocols, with or Without Pre-synchronization

Pre-synchronization strategies with prolonged exposure to exogenous progesterone have the potential to alter estrus expression and improve fertility in replacement beef heifers. The objective of this study was to evaluate the estrus response and pregnancy rate of beef heifers enrolled in two fixed-time artificial insemination (TAI) protocols. A total of 306 heifers (14 ± 2 months of age; 372 ± 24 kg body weight [BW]) at three locations were enrolled in the study. Within location, heifers were stratified by age and BW and randomly assigned to one of two treatments: 1) PG-CIDR54 (n = 152), heifers were administered prostaglandin F2α (PGF; 25 mg) and a controlled internal drug releasing (CIDR) insert (Day -14), an injection of GnRH [100 μg (Day -7)], PGF injection and CIDR removal (Day 0), and a second injection of GnRH concurrently with TAI 54 ± 2 h later (Day 2); 2) 7-day CO-Synch+CIDR (CTRL; n = 154), heifers were administered GnRH (100 μg) and a CIDR insert (Day -7), PGF (25 mg) injection and CIDR removal (Day 0), and a second injection of GnRH concurrently with TAI 54 ± 2 h later (Day 2). All heifers received an estrus alert patch on Day 0 and were evaluated for patch activation at TAI on Day 2. Pregnancy was diagnosed by transrectal ultrasonography between 35 and 55 days after TAI. The percentage of heifers exhibiting estrus between Day 0 and 2 was greater (P < 0.01) in PG-CIDR54 compared with CTRL (77.0 and 39.6%, respectively). In addition, pregnancy rate to TAI tended (P = 0.08) to be greater for PG-CIDR54 compared with CTRL (48.0 and 38.3%, respectively). We conclude that beef heifers enrolled in the PG-CIDR54 protocol had increased estrus expression and tended to have greater pregnancy rate when compared with heifers enrolled in the 7-day CO-Synch+CIDR protocol.

PSXV-26 Late-Breaking: Effects of feeding haylage on the reproductive performance of 2-year-old beef cattle raised in a sustainable production system at Berea college farm

Effects of winter feeding haylage on the growth and reproductive performance of late weaned, summer breeding, rotationally grazed, selectively bred mixed breed cattle (n =90) raised at Berea College Farm during 2015 to 2021 were evaluated. Cattle were grouped based on the year in which they turned 2 years old (2017, 2018, 2019, 2020 and 2021). The 2017 group alone was not fed haylage. Initial data indicated that maintenance of a pre-ruminant gastrointestinal tract during the early developmental years under our management is the main factor impacting cattle performance. Indeed, despite similar birth weights, weaning and yearling weights were numerically higher in 2018 and 2019 compared to 2017 cattle. Significantly higher weaning and yearling weights (264.47 vs 229.37kg and 306.60 vs 253.03kg; P < 0.05) were observed in 2020 versus 2017 cattle, respectively. Additionally, 2018 (426.83kg) but not 2019 (387.38kg) cattle had higher (P < 0.05) liveweights than 2017 (398.93kg) cattle at yearling pregnancy check. At the 2nd breeding, 2018 cattle maintained numerically higher weights than 2019. However, the higher liveweights observed for 2018 cattle compared to that of 2017 cattle at the yearling pregnancy check, was reversed in the following year at the 2-year-old pregnancy check. Consequently, pregnancy rates at the yearling pregnancy check did not differ (89.47 vs 91.67%) but numerically lower retention (31.8 vs 50%) and pregnancy rates (50 vs 75%) were observed for 2018 cattle than 2017 cattle by the 2-year-old pregnancy check, respectively. Additionally, 55% the 2018 cattle displayed ovarian activity and 50% of the 2019 cattle displayed estrus prior bull introduction. In 2019 cattle, 92% were cyclic before introduction of the bull and a 91% estrus response was detected during the breeding season. Feeding haylage promoted growth and reproductive performance of cattle but apparently did not alleviate 2019 drought induced dystocia occurrences during 2020 and 2021 calving seasons.

GPGMH, a New Fixed Timed-AI Synchronization Regimen for Swamp and River Crossbred Buffaloes (Bubalus bubalis)

The crossbreeding of Swamp and River type buffalo breeds is practiced for the improvement of milk yield and reproductive performance in swamp buffalo herds. This study aimed to modify the Ovsynch synchronization protocol (GPG) and improve the fixed-timed artificial insemination (FTAI) for better reproductive performance of crossbred buffaloes. Comparison of four conventional synchronization protocols [pregnant mare gonadotropin-prostaglandin F2α-gonadotropin-releasing hormone (PmPG), gonadotropin-releasing hormone-prostaglandin F2α-gonadotropin-releasing hormone (GPG), prostaglandin F2α-gonadotropin-releasing hormone-prostaglandin F2α-estradiol benzoate (PGPE), and progesterone-pregnant mare gonadotropin-prostaglandin F2α-gonadotropin-releasing hormone (P4PmPG)] in crossbred buffaloes showed that the GPG protocol treated buffaloes displayed higher (P < 0.05) estrus response with an increasing tendency in ovulation (84.6%) and pregnancy rates (30.8%) than PmPG, PGPE, and P4PmPG treated buffaloes. Buffaloes treated with a dose of 0.4 (mg/kg) mifepristone combined with GPG, exhibited higher (P < 0.05) estrous response (82.4%), ovulation (94.1%), and pregnancy (47.1%) rates compared with other doses (0, 0.3, or 0.5 mg/kg) groups. Injection of mifepristone along second GnRH injection in buffaloes improved (P < 0.05) pregnancy rate (35.3%) when compared to before or after the second GnRH of GPG protocol. Single AI after 24 h of mifepristone or second GnRH injection seems the best time to enhance the pregnancy rates in buffaloes compared to double or other single AI times in the modified GPGMH protocol. In comparison, GPGMH reduced the follicular cyst incidence (P < 0.05) with increasing ovulation (P > 0.05) and pregnancy rates (P > 0.05) than the P4GPG and GPG protocols in crossbred buffaloes. The current study supported that new synchronization protocol (modified of GPG protocol; GPGMH) by the inclusion of mifepristone (with a dose of 0.4 mg/kg along second GnRH), AI after 24 h of mifepristone or second GnRH, and human chorionic gonadotropin (hCG at day 5 of AI) enhance the ovulation and pregnancy rates in crossbred buffaloes.

Temporal Changes in Physical Signs of Estrus and Validation of Fetal Parameters for Estimation of Gestational Stage through B-mode Ultrasonography in Beetal goats

The current study evaluates changes in the physical signs of estrus (vulvar hyperemia, edema and mucous discharge) from their onset until ovulation, and validates fetal parameters for the estimation of gestational stage in Beetal goats. In experiment 1, temporal changes in estrus signs were monitored subjectively after the administration of two injections of PGF2α at 10-days interval and a cumulative behavioural index (BI) was calculated in goats that showed estrus response (n=7). Ovulation occurred after 18.8±2.3 h relative to peak vulvar hyperemia and edema; ovulation coincided with maximum mucous discharge (0±2.4 h). Maximum BI was observed between 7 to 31 h after the onset of estrus and was highly correlated with vulvar hyperemia (r=0.94), followed by vulvar edema (r=0.90) and mucous discharge (r=0.85). In experiment 2, fetal parameters were monitored in pregnant goats (n=7) via ultrasonography for estimation of gestational stage, and for validation in a separate set of goats (n=20; experiment 3). Gestational stage correlated significantly (P<0.05) with the uterine diameter (UD), crown-rump length (CRL), trunk diameter (TD), intercostal space (ICS); diameter of amniotic vesicle (AV), biparietal diameter (BPD), placentome diameter (PD) and umbilical cord (UC) diameter. Validation revealed the difference between the actual and estimated day of gestation was less for TD than BPD (4.1±0.6 vs 6.8±1.0 days; P<0.05). In conclusion, vulvar hyperemia, edema, and mucous discharge are highly correlated with BI. Fetal parameters are strongly associated with the gestational stage, and the estimation of the actual gestational stage is less variable through TD than BPD in Beetal goats

Comparison of the reproductive performance of the Kacang goats on three synchronization methods

<p class="MDPI17abstract"><strong><span lang="EN-US">Objective: </span></strong><span lang="EN-US">This study was conducted to investigate the effect of different methods synchronized on the reproductive performance of the Kacang Goats, estrus response, pregnancy rate, kidding rate, twins and litter size.</span></p><p class="MDPI17abstract"><strong><span lang="EN-US">Methods: </span></strong><span lang="EN-US">Forty-five </span><span lang="EN-US">dam of Kacang goats were divided into three groups (n= 15); 1) goats were injected 1 ml PGF</span>_{<span lang="EN-US">2</span>}<span lang="EN-US">α</span><span lang="EN-US"> (Lutalyse^TM) on day 1st and after days 11nd. 2) goats have injected 1 ml of GnRH (Fertagyl^TM) on day 1st and the 7th day was injected 1 ml of </span><span lang="EN-US">PGF</span>_{<span lang="EN-US">2</span>}<span lang="EN-US">α</span><span lang="EN-US">. 3</span><span lang="EN-US">) goats have received 1 ml progesterone (Progesterone-C) on the first day and the 7th day was injected with 1 ml </span><span lang="EN-US">PGF</span>_{<span lang="EN-US">2</span>}<span lang="EN-US">α</span><span lang="EN-US">. Estrus observations were made on the 12th day for the first group, 8th day for the second </span><span lang="EN-US">group and 8th day for the third group. </span><span lang="EN-US">This data analyzed with a t-test. The effects were considered to be significant when the level of probability was less than 5%.<strong></strong></span></p><p class="MDPI17abstract"><strong><span lang="EN-US">Results: </span></strong><span lang="EN-US">The results showed that visualization estrus (goods), </span><span lang="EN-US">t</span><span lang="EN-US">he percentage of estrus (100%), the onset of estrus (51.6 h- 52.6 h), the percentage of pregnancy (100%), birth percentage of kids (100%) Kacang goats </span><span lang="EN-US">better on the use of double PGF₂α and a combination of GnRH and PGF₂α than the use combination progesterone with PGF₂α but </span><span lang="EN-US">the duration of estrus, twins and the kidding rate no difference between treatments.<strong></strong></span></p><p><strong><span lang="EN-US">Conclusions: </span></strong><span lang="EN-US">Synchronization method using a combination of GnRH with PGF</span>_{<span lang="EN-US">2</span>}<span lang="EN-US">α</span><span lang="EN-US"> and double PGF</span>_{<span lang="EN-US">2</span>}<span lang="EN-US">α</span><span lang="EN-US"> produces estrus responses, pregnancy rate and birth rates that are higher than the combination Progesterone with PGF</span>_{<span lang="EN-US">2</span>}<span lang="EN-US">α</span><span lang="EN-US"> synchronization method.</span></p>

PSIII-7 Determining the requirement of puberty induction to the reproductive performance of Bos indicus-influenced heifers submitted to AI

Induction of puberty by treating heifers with progesterone (P4) inserts may favor pregnancy/AI (P/AI) to a subsequent estrus synchronization program. However, it remains to be elucidated whether induction is required when the synchronization program contains P4 supplementation. To address this question, yearling, Brahman-influenced heifers (mostly 3/8 Brahman) classified as pubertal (PUB; n = 363) or prepubertal (PRE; n = 214) based on the presence of a CL, were assigned to receive no P4 supplementation (NoCIDR) or a CIDR for 10 days, starting on D-23. On D-13, all heifers received a dose of prostaglandin analogue and CIDRs were removed. On D-9, all heifers were enrolled in a 6-day CIDR & TAI protocol. Heifers were serviced based on heat between D-2 and D0 or were TAI on D0. Reproductive tract scores (RTS, 1 to 5 scale) were evaluated on D-23 and D-3. Induction increased the proportion of PRE heifers bearing a CL on D-3 (PRE|CIDR: 60.3% vs. PRE|NoCIDR: 42.7%). Among heifers with CL on D-3, P/AI of PRE heifers (42.5%) was similar to that PUB (47.7%). Conversely, for heifers without CL on D-3, P/AI of PRE (14.7%) was lower than PUB (37.3%). RTS increased between D-23 and D-3 from 2.3 to 4.0 (CIDR) and 2.3 to 3.6 (NoCIDR). For every 1-point increase in RTS, P/AI was 6–9% greater. Despite hastened puberty, P/AI of PRE heifers were less (PRE|NoCIDR: 29.2% and PRE|CIDR: 30.4%) than that of PUB (PUB|NoCIDR: 50.7% and PUB|CIDR: 42.2%). Less PRE (42.5%) than PUB animals (69.7%) were AI at estrus, and heifers showing estrus had a higher P/AI (52.8% vs. 18.7%). In conclusion, induction is not required when the subsequent synchronization protocol for AI contains progesterone. Induction hastened puberty attainment but failed to improve estrus response and fertility to the synchronization protocol.

130 Presynchronization with Prostaglandin F2αand prolonged exposure to exogenous progesterone impacts estrus expression and alters fertility in beef heifers

To determine the effects of 2 presynchronization strategies in conjunction with delayed fixed-time artificial insemination (TAI) on pregnancy rates to TAI (PR/AI), 1,700 Angus beef heifers at 3 locations were enrolled in a completely randomized design with a 2×2 factorial arrangement of treatments. Within location, all heifers were randomly assigned to 1 of 4 treatments: 1) PG54 (n = 434), heifers received a 25-mg injection of prostaglandin F2α (PGF) 7 d prior (d -14) to the initiation of the 7-d CO-Synch + CIDR protocol wherein they received a 100-µg injection of gonadotropin-releasing hormone (GnRH) and a CIDR insert on d -7, a 25-mg injection of PGF at CIDR removal on d 0, and a second injection of GnRH concurrently with TAI 54±2 h later; 2) PG72 (n = 426), heifers were exposed to the same treatment as PG54; however, TAI was performed 72 ± 2 h after CIDR removal; 3) PG-CIDR54 (n = 422), same as PG54 but heifers received a CIDR insert on d -14 in addition to PGF; 4) PG-CIDR72 (n = 418), same as PG-CIDR54; however, TAI was performed 72±2 h after CIDR removal. Estrus detection patches were applied to all heifers on d 0 and were evaluated for activation at TAI. Pregnancy was diagnosed between 30 and 47 d after TAI. The percentage of heifers exhibiting estrus between d 0 and TAI was greater (P &lt; 0.001) in the PG72, PG-CIDR54, and PG-CIDR72 treatments compared to the PG54 treatment (78.11, 86.59, and 91.09 vs. 31.05%, respectively). Furthermore, estrus response was greater (P &lt; 0.001) in PG-CIDR72 heifers when compared to PG72. Pregnancy rates to TAI differed among treatments and were greater (P &lt; 0.05) in the PG72 and PG-CIDR54 treatments when compared to PG-CIDR72 (48.8 and 50.4 vs. 38.4%, respectively), and were greater (P = 0.034) in PG-CIDR54 vs. PG54 (43.1%). Moreover, a tendency (P = 0.097) was determined on PR/AI between PG54 and PG72. In conclusion, presynchronization strategies and prolonged exposure to exogenous progesterone have the potential to alter estrus expression and improve fertility in replacement beef heifers.