ABSTRACT The aim of this study was to evaluate the effects of injectable mineral and vitamin supplementation on reproductive and productive performance in grazing cows. Seventy-two cows were assigned to the following groups: (1) control (CON, n=18); (2) injectable mineral supplementation (SIM, n=18); (3) injectable vitamin supplementation (SIV, n=18); and (4) SIMV (SIM + SIV) (n=18). IM supplementation was done 20 days before calving, on the day of calving and 30 days after delivery. SIM, SIV and SIMV treatments resulted in a decreased calving interval to first artificial insemination and improved milk production. The injection of vitamins or minerals did not differ from the control group in number of assisted calving, retained placenta, interval from calving to conception and pregnancy rate according to the number of inseminations.

RESUMEN El objetivo del estudio fue evaluar los efectos de la suplementación inyectable de minerales y vitaminas sobre el desempeño reproductivo y productivo en vacas en pastoreo. Setenta y dos vacas se asignaron a los siguientes grupos: (1) control (CON, n=18); (2) suplementación inyectable de minerales (SIM, n=18); (3) suplementación inyectable de vitaminas (SIV, n=18); y (4) SIMV (SIM + SIV) (n=18). La suplementación vía IM se hizo a 20 días del preparto, el día del parto y 30 días después del parto. Los tratamientos de SIM, SIV y SIMV resultaron en una disminución del intervalo del parto hasta la primera inseminación artificial y mejora de la producción de leche. La inyección de vitaminas o minerales no difirió con el grupo control en número de partos asistidos, retenciones placentarias, intervalo desde el parto hasta la concepción y tasa de preñez según el número de inseminaciones.

ABSTRACT The aim of this study was to evaluate the efficiency of artificial insemination (AI) services in Holstein x Brahman cows under a heat induction programme. Three experiments were carried out. In Exp. 1, a retrospective analysis of the efficiency of AI insemination of 41 000 cows treated with the combination of progesterone and oestradiol benzoate or equine chorionic gonadotropin (eCG) was carried out. In Exp. 2 it was evaluated 863 cows inseminated after heat induced with progesterone and oestradiol benzoate to know the physiological events that occur before and after service in herds with a high incidence of anoestrus. Gynaecological examinations and determination of progesterone in milk were performed. The purpose of Exp. 3 was to improve the effectiveness of AI services for cows in postpartum anoestrus treated with progesterone and oestradiol benzoate combined with a technique to identify and induce the return to service of females that did not conceive. Only 30% of the cows exceeded 40% conception. The best results were obtained when using eCG (47% vs 29%). The problems associated with the low conception rate were unfertilized oestrus, embryonic mortality and anoestrus after breeding (Exp. 2). The return to service induction technique increased (p<0.001) the conception rate of the second induced service and the percentage of accumulated pregnancy in the treated group compared to the control (69.0 and 32.0%, respectively) (Exp. 3).

RESUMEN El trabajo tuvo como objetivo evaluar la eficiencia de los servicios de inseminación artificial (IA) en vacas Holstein x Brahman bajo programa de inducción del celo, Se realizaron tres experimentos. En el Exp. 1 se efectuó un análisis retrospectivo de la eficiencia de la inseminación artificial de 41 000 vacas tratadas con la combinación de progesterona y benzoato de estradiol o gonadotropina coriónica equina (eCG). En el Exp. 2 se trabajó con 863 vacas inseminadas de celo inducido con progesterona y benzoato de estradiol para conocer los eventos fisiológicos que ocurren antes y después del servicio en rebaños con alta incidencia de anestro. Se hicieron exámenes ginecológicos y determinación de progesterona en leche. El Exp. 3 tuvo como fin mejorar la eficacia de los servicios de IA de vacas en anestro posparto tratadas con progesterona y benzoato de estradiol combinado con una técnica para identificar e inducir el retorno al servicio de las hembras que no llegasen a concebir. Solo 30% de las vacas superaron el 40% de concepción. Los mejores resultados se obtuvieron al utilizar la eCG (47% vs 29%). Los problemas asociados a la baja tasa de concepción fueron los celos no fertilizados, la mortalidad embrionaria y el anestro posterior al servicio (Exp. 2). La técnica de inducción del retorno al servicio aumentó (p<0.001) la tasa de concepción del segundo servicio inducido y el porcentaje de preñez acumulada en el grupo tratado respecto al testigo (69.0 y 32.0%, respectivamente) (Exp. 3).

Abstract The breeding of replacement heifers in breeding systems is an important factor that directly affects the productivity of livestock companies. The aim of this study was to assess the reproductive performance of replacement heifers during their first breeding season, considering morphostructural and reproductive development variables. 142 zebu cross females of 22 to 24 months of age were used, previously selected by weight (a minimum of 67% of the estimated weight for an adult cow under the system was considered). An observational design was used before service in which they were divided into 3 groups according to the degree of reproductive development (RTS 1 to 3), live weight (LW), body condition (BCS 1-9), and zoometric measurements. The service was carried out by artificial insemination at a fixed time (TAI) and natural service (NS). The pregnancy diagnosis was carried out 32 days after the TAI and 35 days after the bulls were removed for NS. The results showed significant differences between the growth and development variables, except in cannon bone circumference and rump height. For LW the RTS1 were 10% heavier than the RTS3. The χ2 test identified association between NS and RTS with 50, 82 and 32%, as well as in general pregnancy of 84, 92 and 67% pregnancy in RTS1, 2 and 3, respectively. In conclusion, for the pre- breeding selection of replacement heifers, it is essential to consider not only live weight but also the degree of reproductive development and zoometric variables.

Resumen La recría de vaquillonas de reposición en sistemas de cría es un factor importante que afecta directamente la productividad de las empresas ganaderas. El objetivo de este estudio fue evaluar el desempeño reproductivo de vaquillonas en el primer servicio, considerando variables morfoestructurales y de desarrollo reproductivo. Se utilizaron 142 hembras de 22 a 24 meses de edad cruza cebú, previamente seleccionadas por peso (se consideró un mínimo de 67% del peso estimado para una vaca adulta bajo el sistema). Se utilizó un diseño observacional antes del servicio en el que se dividieron en 3 grupos según, grado de desarrollo reproductivo (GDR 1 a 3), peso vivo (PV), condición corporal (CC 1-9) y mediciones zoométricas. El servicio fue realizado mediante inseminación artificial a tiempo fijo (IATF) y servicio natural. El diagnóstico de gestación se llevó a cabo a los 32 días luego de la IATF y 35 días después de retirados los toros para el servicio natural. Los resultados demostraron diferencias significativas entre las variables de crecimiento y desarrollo, excepto en perímetro de la caña y alzada a la grupa. Para PV las GDR1 fueron 10% más pesadas que las GDR3. La prueba de χ2 encontró asociación entre servicio natural y GDR con 50, 82 y 32%, como así también en la preñez general de 84, 92 y 67% de preñez en GDR 1, 2 y 3, respectivamente. En conclusión, para la selección pre-servicio en vaquillonas de reposición, es importante considerar no solo el peso vivo, sino también el grado de desarrollo reproductivo y las variables zoométricas.

Resumen El desempeño reproductivo es crucial para la rentabilidad de la producción doble propósito en la Amazonía Ecuatoriana. Evaluar tres protocolos para Inseminación Artificial a tiempo fijo (IATF) en vacas en lactancia de doble propósito. Vacas Pardo Suizo en lactancia (n=301) recibieron 2 mg de benzoato de estradiol (EB) y un dispositivo intravaginal con 0,5 g de progesterona (P4) el Día 0 y fueron asignadas aleatoriamente en tres grupos. Las vacas del grupo EB recibieron 500 μg de cloprostenol (PGF2α) y se les retiró el dispositivo el Día 7, y recibieron 1 mg de EB el Día 8. Las vacas del grupo ECP fueron tratadas como las del grupo EB, excepto que recibieron 0,5 mg de cipionato de estradiol (ECP) en el día del retiro del dispositivo (Día 7) en lugar de EB el Día 8. En las vacas del grupo J-Synch, el retiro del dispositivo y la administración de PGF2α se realizaron el Día 6. Todas las vacas fueron IATF el Día 9 y las del grupo J-Synch recibieron 100 μg de gonadorelina en ese momento. Aunque el diámetro del folículo dominante y del CL fueron mayores (P<0,05) en las vacas del grupo J-Synch, las tasas de preñez a la IATF no difirieron entre los grupos (EB: 51,0%, ECP: 53,0% y J-Synch: 59,4%). Los tres protocolos probados se pueden aplicar con éxito en vacas de doble propósito amamantando.

Abstract Reproductive performance is crucial for profitability of dual-purpose cow-calf production in the Ecuadorian Amazon. To evaluate three different fixed-time artificial insemination (FTAI) protocols in suckled, dual-purpose cows in the Ecuadorian Amazon. Lactating, Brown Swiss cows (n=301) received 2 mg estradiol benzoate (EB) and an intravaginal device containing 0.5 g of progesterone (P4) on Day 0. They were allocated randomly into the following three treatment groups: Cows in the EB group received 500 μg cloprostenol (PGF2α), and P4 devices were removed on Day 7, and 1 mg EB was administered on Day 8. Cows in the ECP group were treated as those in the EB group, except that they received 0.5 mg estradiol cypionate (ECP) at the time of P4 device removal on Day 7 instead of EB on Day 8. Cows in the J-Synch group had the P4 device removed and PGF2α administered on Day 6. All cows were FTAI on Day 9; cows in the J-Synch group also received 100 μg gonadorelin at that time. Although the diameter of the dominant follicle and the resulting CL were greater (P<0.05) in cows in the J-Synch group, pregnancies per AI did not differ (P>0.2) among groups (EB: 51.0%, ECP: 53.0% and J-Synch: 59.4%). The three protocols tested were applied successfully in suckled, dual-purpose cows with no differences in pregnancies per AI.

ABSTRACT: This study evaluated the probability of pregnancy and associated factors for two times artificial inseminations (AI), 8 or 10 hours after automated activity monitoring (AAM) alarm on the first postpartum AI of 1,054 Holstein dairy cows. The estrus was synchronized by prostaglandin or estradiol-progesterone program. Stepwise logistic regression was performed to analyze the probability of pregnancy, and associated factors (activity, estrus intensity, parity, peripartum health, retained placenta, postpartum vaginal discharge, and season). The highest pregnancy rates were obtained with multiparous animals, inseminated ten hours after the AAM alarm, in the fall or winter season, with a high activity peak and estrus intensity (P < 0.05). Peripartum diseases, retained placenta, and postpartum vaginal discharge negatively influenced the pregnancy rate, regardless of parity. Thus, the optimization of AAM models by including on-farm measures like parity, peripartum health history, and environmental conditions may favor the correct identification of estrus and improve the AAM alarm regarding the ideal moment for AI, increasing the reproductive performance in dairy cows. ABSTRACT , (AI) 1 (AAM 1054 054 1,05 cows estradiolprogesterone estradiol progesterone program activity, (activity parity placenta season. season . season) animals P 0.05. 005 0.05 0 05 0.05) diseases rate Thus onfarm farm history (AI 105 1,0 00 0.0 1, 0.

RESUMO: O objetivo deste estudo foi avaliar a probabilidade de prenhez e fatores associados para dois horários de inseminação artificial (IA), oito ou 10 horas após o alarme de monitoramento automatizado de atividades (AAM), na primeira IA pós-parto em 1.054 vacas leiteiras da raça Holandês. O estro foi sincronizado por protocolos a base de prostaglandina ou estradiol-progesterona. Regressão logística stepwise foi realizada para analisar a probabilidade de prenhez e fatores associados (atividade, intensidade do estro, paridade, saúde no periparto, placenta retida, descarga vaginal pós-parto e estação do ano). As maiores taxas de prenhez foram obtidas em multíparas, inseminadas 10 horas após o alarme do AAM, no outono ou inverno, com pico de atividade elevado e intensidade de estro (P < 0,05). Doenças no periparto, placenta retida e descarga vaginal pós-parto influenciaram negativamente a taxa de prenhez, independentemente da paridade. Assim, a otimização dos modelos de AAM, incluindo medidas rotineiras da fazenda como paridade, histórico de saúde no periparto e condições ambientais, podem favorecer a identificação correta do estro e melhorar o alarme do AAM em relação ao momento ideal para a IA, aumentando o desempenho reprodutivo nas vacas leiteiras. RESUMO , (IA) 1 (AAM) pósparto pós parto 1054 054 1.05 Holandês estradiolprogesterona. estradiolprogesterona estradiol progesterona. progesterona estradiol-progesterona atividade, (atividade paridade ano. ano . ano) multíparas inverno P 0,05. 005 0,05 0 05 0,05) Assim ambientais (IA (AAM 105 1.0 00 0,0 1. 0,

Abstract This study aimed to analyze the characteristics of the HSP70 gene and protein in spermatozoa of Bali bulls of different age groups and to examine its potential as a biomarker determining bull fertility. This study used frozen semen produced from six Bali bulls divided into two groups based on age (≤ 9 years and ≥ 12 years). Parameters of frozen semen quality analyzed included sperm motility and kinetics using computer-assisted semen analysis, sperm morphological defects using Diff-Quick staining, acrosome integrity using FITC-PNA staining, and DNA fragmentation using acridine orange staining. HSP70 gene expression characterization was analyzed using qRT-PCR, and HSP70 protein abundance was analyzed using enzyme immunoassays. Fertility field data were obtained by analyzing the percentage conception rate for each bull based on the artificial insemination service data contained in the Indonesian-integrated system of the National Animal Health Information System (iSIKHNAS). The results showed significant differences (P<0.05) in total and progressive motility, morphological defects of the neck and midpiece, and tail of sperm, and acrosome integrity between the age groups of Bali bulls. HSP70 gene expression and protein abundance showed no significant differences (P>0.05) in different age groups. HSP70 gene expression correlated with fertility rate (P<0.05). Age affected several semen quality parameters but did not affect HSP70 gene expression and protein abundance. The HSP70 gene molecule could be a biomarker that determines the fertility of Bali bulls. HSP HSP7 ≤ ( 1 years. . years) computerassisted computer assisted analysis DiffQuick Diff Quick staining FITCPNA FITC PNA qRTPCR, qRTPCR qRT PCR, PCR qRT-PCR immunoassays Indonesianintegrated Indonesian integrated iSIKHNAS. iSIKHNAS (iSIKHNAS) P<0.05 P005 P 0 05 (P<0.05 midpiece P>0.05 (P>0.05 P<0.05. (iSIKHNAS P<0.0 P00 (P<0.0 P>0.0 (P>0.0 P<0. P0 (P<0. P>0. (P>0. P<0 (P<0 P>0 (P>0 P< (P< P> (P> (P

Abstract The impact of GnRH treatment on the day of TAI in beef cows has received limited investigation, especially concerning its association with estrus expression. Consequently, two experiments were conducted to assess the potential of GnRH treatment on the day of TAI to enhance fertility according to the expression or not of estrus in beef cows. Experiment 1 aimed to determine ovulation rate and luteal function, while Experiment 2 aimed to determine the effect of the two GnRH treatment approaches on pregnancy rate. In Experiment 1, multiparous Brangus suckling cows (n = 17) were submitted to an 8-day TAI protocol. Estrus occurrence was evaluated based on chalk removal on D10 (TAI) and cows were assigned to receive GnRH (25µg lecirelin; im) according to the group: GnRH (n = 7), regardless of estrus expression; or selectGnRH (n = 10), only cows not detected in estrus. Ovulation rate occurring until 77h after IVD removal did not differ (p = 0.17) between GnRH (85.7%; 6/7) and selectGnRH (100%; 10/10). Also, corpus luteum size and serum progesterone concentration were not affected (p>0.05) by treatments. In Experiment 2, crossbred taurine suckled cows (n = 384) were submitted to the same protocol as described in Experiment 1 and were randomly allocated to GnRH or selectGnRH groups. There was no difference in P/AI between groups (selectGnRH = 55.6%; GnRH = 54.3%; p = 0.7) 30 days after TAI. As expected, there was a pronounced effect (p<0.0001) of estrus expression on P/AI (Estrus = 61.5%; No estrus = 33.0%), regardless of group. In summary, ovulation timing and rate and luteal function did not differ between groups. Also, GnRH administration only in cows that do not show estrus is recommended, considering hormone savings and similar conception rate. investigation Consequently n 17 8day 8 D D1 (TAI 25µg µg lecirelin im group 7, 7 , 7) 10, 10 10) h 0.17 017 0 85.7% 857 85 (85.7% 6/7 67 6 100% 100 (100% 10/10. 1010 10/10 . 10/10) Also p>0.05 p005 05 (p>0.05 treatments 384 PAI P AI 55.6% 556 55 54.3% 543 54 3 0.7 07 expected p<0.0001 p00001 0001 (p<0.0001 61.5% 615 61 5 33.0%, 330 33.0% 33 33.0%) summary recommended 0.1 01 85.7 (85.7 6/ (100 101 10/1 p>0.0 p00 (p>0.0 38 55.6 54.3 0. p<0.000 p0000 000 (p<0.000 61.5 33.0 85. (85. (10 10/ p>0. p0 (p>0. 55. 54. p<0.00 p000 00 (p<0.00 61. 33. (85 (1 p>0 (p>0 p<0.0 (p<0.0 (8 ( p> (p> p<0. (p<0. p<0 (p<0 p< (p<

Abstract Since the 1970s, maternal corticosteroid therapy has been used successfully to induce labor. This allows for better monitoring of parturients and provision of first aid to neonates, improving neonatal viability, as this treatment induces maturation in a variety of fetal tissues, thereby reducing morbidity and mortality. Although the effects of corticosteroids are well known, few studies have investigated the influence of this therapy in Santa Inês sheep. This study aimed to evaluate the efficacy of dexamethasone at two doses (8 and 16 mg) to induce lambing in Santa Inês ewes at 145 days of gestation and assess its effects on neonatal vitality. For this study, 58 ewes raised in an extensive system were investigated. Pregnancy was confirmed after artificial insemination at a set time or after controlled mounting. Ewes were separated into three groups: an untreated control group (G1: 0 mg) and groups treated with two doses of dexamethasone (G2: 8 mg and G3: 16 mg). In total, 79 lambs were born. Their vitality was assessed based on their Apgar score, weight, temperature, and postnatal behavior. SAS v9.1.3 (SAS Institute, Cary, NC) was used to analyze data, considering a 5% significance level for all analyses. The births in the induced groups occurred 48.4 ± 22.1 h after induction, while the ewes that underwent non-induced labor gave birth 131.96 ± 41.9 h after placebo application (p < 0.05), confirming the efficacy of dexamethasone to induce and synchronize labor. The induced and non-induced neonates had similar Apgar scores, temperatures, weights, and postnatal behavioral parameters (p > 0.05). This study showed that inducing labor in Santa Inês ewes at 145 days of gestation with a full (16 mg) or half dose (8 mg) of dexamethasone is an effective technique and does not compromise neonate vitality. 1970s s viability tissues mortality known sheep ( 1 14 5 mounting G1 G (G1 G2 (G2 G3 mg. . total 7 born score weight temperature behavior v913 v v9 3 v9.1. Institute Cary NC data analyses 484 48 4 48. 221 22 22. induction noninduced non 13196 131 96 131.9 419 41 9 41. p 0.05, 005 0.05 , 05 0.05) scores temperatures weights 0.05. (1 (G v91 v9.1 2 1319 13 131. 00 0.0 v9. 0.

Abstract We hypothesized that the hCG modulates the expression of IFNT-pathway and ISGs in bovine endometrium during early pregnancy. The aim of the current study is to evaluate the effect of hCG on IFNT-pathway signals and ISGs expression in endometrial cells. For this, 29 non-lactating cross-bread cows were used in the study and submitted to a 9-day fixed-time artificial insemination (FTAI) protocol. The day of the AI was considered Day 0 (D0), and five days (D5) after the FTAI, the cows were allocated into two groups: Control and hCG group, when a hCG group received a single dose of 2.500UI of hCG. On day 18 after FTAI (D18) cows were slaughtered and endometrial tissue samples were collected. There was no difference between the embryo recovery rate of the cows in C compared to the hCG. The hCG group increased the accessory corpus luteum formation rate. The hCG resulted in greater serum progesterone concentration in the hCG group compared to the C on Day 14. Only the expression of IFNAR2 and STAT1 were upregulated on pregnant cows of the hCG group compared to the C group. The pathway genes (JAK1, STAT2, and IRF9) were not regulated. The mRNA abundance of ISG15, MX1, MX2, and OAS1 was upregulated in pregnant cows for hCG group, compared to C group. The results show that the administration of hCG, 5 days after AI, in addition to increasing the serum progesterone, modulates the expression of IFNT-pathway and ISGs on bovine endometrium on Day 18 of pregnancy. IFNTpathway IFNT pregnancy cells this 2 nonlactating non lactating crossbread cross bread 9day 9 fixedtime fixed time (FTAI protocol D0, D0 D , (D0) D5 (D5 groups 2500UI UI 500UI 1 D18 (D18 collected 14 IFNAR STAT JAK1, JAK1 JAK (JAK1 STAT2 IRF9 IRF regulated ISG15 ISG MX1 MX MX2 OAS (D0 (D D1 (D1 (JAK ISG1

Abstract This study aimed to evaluate the efficiency of two or three estrus synchronizations followed by artificial insemination (AI) by laparoscopy with frozen semen in sheep. Santa Inês sheep (n=147) were randomly distributed into two groups: Re-sync - 2FTAI (n=72) and Doppler - 3FTAI (n=75), synchronized with a short protocol associated with GnRH and AI by laparoscopy with frozen semen 50 h after removing the P4 device (D0). Two AIs were performed in the Re-sync group, with the start of the resynchronization protocol on D23 and gestational diagnosis on D30; the non-pregnant females were inseminated again. The sheep were resynchronized (D10) in the Doppler group and the gestation diagnosis was made early at 17 days using Doppler ultrasound. The open females were inseminated again, totaling three inseminations in 42 days. Early gestation diagnoses were confirmed at 30 days. Re-sync (29.16%) and Doppler (21.33%) were similar to each other in terms of cumulative gestation rate (P>0.05). The indicators of the non-gestation diagnosis technique at 17 days were sensitivity of 100%, specificity of 28%, positive predictive value of 21.3%, negative predictive value of 100%, and accuracy of 39.8%. Early diagnosis allowed sheep to be inseminated two to three times in the same period and was effective in diagnosing truly non-pregnant females. Therefore, estrus resynchronization associated with AI by laparoscopy using frozen semen can be applied in sheep, but a higher gestation rate could not be achieved with two or three inseminations at the end of the breeding season. (AI n=147 n147 n 147 (n=147 groups Resync Re sync FTAI n=72 n72 72 (n=72 n=75, n75 n=75 , 75 (n=75) 5 P D0. D0 D . (D0) D2 D30 nonpregnant non pregnant again D10 (D10 1 ultrasound 4 3 29.16% 2916 29 16 (29.16% 21.33% 2133 21 33 (21.33% P>0.05. P005 P>0.05 0 05 (P>0.05) nongestation 100 100% 28 28% 213 21.3% 398 39 8 39.8% Therefore season n=14 n14 14 (n=14 n=7 n7 7 (n=7 (n=75 (D0 D3 D1 (D1 29.16 291 2 (29.16 21.33 (21.33 P00 P>0.0 (P>0.05 10 21.3 39.8 n=1 n1 (n=1 n= (n= (D 29.1 (29.1 (21.3 P0 P>0. (P>0.0 21. 39. (n 29. (29. (21. P>0 (P>0. (29 (21 P> (P>0 (2 (P> ( (P

Resumo Objetivou-se avaliar a eficiência de duas ou três sincronizações de estro seguida da inseminação artificial (IA) por laparoscopia com sêmen congelado em ovinos. As ovelhas Santa Inês (n=147) foram distribuídas aleatoriamente em 2 grupos: Re-sync - 2IATF (n=72) e Doppler - 3IATF (n=75), sincronizadas com protocolo curto associado ao GnRH e IA por laparoscopia com sêmen congelado 50 horas após a retirada do dispositivo P4 (D0). No grupo Re-sync foram realizadas duas IA com início do protocolo de ressincronização em D23 e diagnóstico gestacional em D30, as fêmeas não gestantes eram inseminadas novamente. No grupo Doppler as ovelhas foram ressincronizadas (D10) e o diagnóstico de gestação realizado precocemente aos 17 dias, com auxílio da ultrassonografa Doppler. As fêmeas vazias eram inseminadas novamente, totalizando três inseminações em 42 dias. Os diagnósticos precoces de gestação foram confirmados com 30 dias. Re-sync (29,16%) e Doppler (21,33%), foram semelhantes entre si na taxa de prenhez acumulativa (P>0,05). Os indicadores da técnica de diagnóstico de não-gestação aos 17 dias foram: sensibilidade 100%, especificidade 28%, valor preditivo positivo 21,3%, valor preditivo negativo 100% e acurácia 39,8%. Com o auxílio do diagnóstico precoce as ovelhas puderam ser inseminadas de duas a três vezes no mesmo período e mostrou efetividade em diagnosticar as fêmeas verdadeiramente não gestante. Conclui-se que a ressincronização de estro associada a IA por laparoscopia utilizando sêmen congelado pode ser aplicada em ovinos, entretanto não foi possível alcançar maior taxa de prenhez com duas ou três inseminações ao final da estação de monta. Objetivouse Objetivou se (IA ovinos n=147 n147 n 147 (n=147 grupos Resync Re sync IATF n=72 n72 72 (n=72 n=75, n75 n=75 , 75 (n=75) 5 P D0. D0 D . (D0) D2 D30 novamente D10 (D10 1 4 3 29,16% 2916 29 16 (29,16% 21,33%, 2133 21,33% 21 33 (21,33%) P>0,05. P005 P>0,05 0 05 (P>0,05) nãogestação 100 28 28% 213 21,3% 398 39 8 39,8% gestante Concluise Conclui monta n=14 n14 14 (n=14 n=7 n7 7 (n=7 (n=75 (D0 D3 D1 (D1 29,16 291 (29,16 21,33 (21,33% P00 P>0,0 (P>0,05 10 21,3 39,8 n=1 n1 (n=1 n= (n= (D 29,1 (29,1 (21,33 P0 P>0, (P>0,0 21, 39, (n 29, (29, (21,3 P>0 (P>0, (29 (21, P> (P>0 (2 (21 (P> ( (P

ABSTRACT This observational study describes the short- and long-term effects of maternal factors in 226 Holstein heifers and their offspring. We obtained maternal data and information from the dairy register. Young heifers were assessed in the window of 60 to 105 days of life to perform the Calf Health Scoring System and performance index, and blood samples to measure inflammatory biomarkers. Prospective data on reproduction were obtained from dairy farm registers. The eutocic weight was higher than the dystocic calving heifers. Plasma total protein and weight were higher in the offspring of multiparous dams than in those of primiparous dams. Calves that were born lighter and in summer had lower concentrations of total protein and performance indices. The punctuation of the fecal score was higher in calves born in summer and cold months for BRD. Offspring from multiparous dams born at term exhibited greater precocity in terms of age at first artificial insemination and first parturition. Finally, seasonality at birth affected pregnancy loss and age at first calving. Heifers born in winter had lower rates of pregnancy loss than those born in summer. In addition, these animals were more precocious than animals born during the cold seasons. short longterm long 22 register 6 10 index biomarkers registers indices BRD parturition Finally addition seasons 2 1

RESUMO Este estudo observacional descreve os efeitos de curto e longo prazo de fatores maternos em 226 novilhas Holandesas e suas proles. Foram obtidos dados maternos e informações do registro leiteiro. Novilhas jovens foram avaliadas, na janela de 60 a 105 dias de vida, com o escore de saúde, índice de desempenho e amostras de sangue para medir biomarcadores inflamatórios. Dados prospectivos sobre reprodução foram obtidos dos registros da fazenda. O peso das novilhas eutócicas foi superior ao das novilhas que nasceram de parto distócico. A proteína total plasmática e o peso foram maiores nas proles de vacas multíparas do que nas proles das primíparas. Bezerras que nasceram mais leves e no verão apresentaram menores concentrações de proteína total e índices de desempenho. A pontuação do escore fecal foi maior em bezerras nascidas no verão e nos meses frios para DRB. A prole de vacas multíparas nascidas a termo apresentou maior precocidade em relação à idade à primeira inseminação artificial e ao primeiro parto. Finalmente, a sazonalidade ao nascimento afetou a perda de prenhez e a idade ao primeiro parto. As novilhas nascidas no inverno tiveram menores taxas de perda de gestação do que as nascidas no verão. Além disso, esses animais eram mais precoces do que os nascidos nas estações frias. 22 leiteiro avaliadas 6 10 vida saúde inflamatórios fazenda distócico primíparas DRB Finalmente disso frias 2 1

ABSTRACT The objective of this study was to identify parameters, before the start of the breeding season, that affect the conception rate of precocious Nelore heifers through ultrasonographic ovarian evaluation and evaluation of weight and body condition score (BCS). A total of 407 heifers aged 404±69 days (≈14 months old), weighing 267.1±31.2 kg, and with mean BCS of 3.1±0.5, were used. Heifers were subjected to hormone treatment to induce cyclicity and, 30 days later, to a fixed-time artificial insemination (FTAI) program with three managements. Morphometric measurements of ovaries and ovarian structures were performed by transrectal ultrasonographic evaluation, as well as weighing and evaluation of BCS on D −30 and D0. Conception rate was evaluated 30 days after FTAI. The conception rate of heifers did not vary according to ovary diameter, weight, BCS, and age at first calving. However, heifers with the presence of follicle with a diameter > 6 mm at D −30 and D0 had a higher conception rate at the first FTAI. The presence of a dominant follicle greater than 6 mm at D −30 is an efficient complementary criterion to identify 14-month-old Nelore heifers with greater ability to conceive at the first FTAI before the breeding season. Antral follicle count performed on D −30 is not a good tool to predict fertility at the first FTAI, and the weight may not be a limiter to select heifers under good nutritional and health management. parameters season BCS. . (BCS) 40 40469 404 69 404±6 ≈14 14 (≈1 old, old , old) 2671312 267 1 31 2 267.1±31. kg 3105 3 0 5 3.1±0.5 used later fixedtime fixed time (FTAI managements −3 calving However 14monthold monthold month management (BCS 4 4046 404± ≈1 (≈ 267131 26 267.1±31 310 3.1±0. − ≈ ( 26713 267.1±3 3.1±0 2671 267.1± 3.1± 267.1 3.1 267. 3.

RESUMO Este estudo teve como objetivo avaliar o comportamento sexual e as características de condicionamento de reprodutores bubalinos submetidos à coleta de sêmen com vagina artificial. Trinta touros foram avaliados durante as estações reprodutivas favorável (março a maio) e desfavorável (novembro e dezembro), em propriedade localizada no estado de Minas Gerias, Brasil (latitude 20°41'45'' Sul e longitude 44º49'37'' Oeste ). Os dados foram analisados descritivamente de acordo com o sucesso ou não da ejaculação, usando-se uma série de parâmetros comportamentais. Uma análise de regressão logística multinível foi realizada utilizando-se as respostas e as variáveis explicativas mencionadas acima. Os resultados mostraram que, quando mais de três parâmetros se manifestam, a chance de se obter ejaculação aumenta em 9,0%, valor que sobe para 28,2% quando se observam sete a nove parâmetros manifestados pelos reprodutores. Essas observações permitem concluir que é possível condicionar touros sexualmente maduros para coleta de sêmen por meio da vagina artificial para uso em programas de inseminação artificial e inseminação artificial em tempo fixo. março maio novembro dezembro, dezembro , dezembro) Gerias latitude 20°4145 204145 20°41 45 20 41 20°41'45' 44º4937 º 44º49 37 44º49'37' . ) usandose usando comportamentais utilizandose utilizando acima manifestam 90 9 0 9,0% 282 28 2 28,2 fixo 4145 20°414 20414 2041 20°4 4 20°41'45 44º493 44º4 3 44º49'37 9,0 28, 414 204 20° 20°41'4 44º 44º49'3 9, 20°41' 44º49'

ABSTRACT This study aimed to evaluate the sexual behavior and accommodation characteristics of buffalo recipients patented for semen collection with an artificial vagina. Thirty bulls were sampled during favorable (March to May) and unfavorable (November to December) breeding seasons in a property located in the state of Minas Gerais, Brazil (Latitude 20°41'45'' South and Longitude 44°49'37'' West). Data were analyzed descriptively according to whether ejaculation was successful, using a range of behavioral parameters. A multilevel logistic regression analysis was performed using the responses and explanatory variables mentioned above. The results show that when more than three parameters are manifested, the chance of obtaining ejaculation increases by 9.0%, a value that rises to 28.2% when seven to nine parameters manifested by the breeders are observed. These observations allow us to conclude that it is possible to condition sexually mature bulls for semen collection through the artificial vagina for use in artificial insemination and fixed-time artificial insemination programs. March May November December Gerais Latitude 20°4145 204145 20°41 45 20 41 20°41'45' 44°4937 444937 44°49 37 44 49 44°49'37' West. West . West) successful above 90 9 0 9.0% 282 28 2 28.2 observed fixedtime fixed time programs 4145 20°414 20414 2041 20°4 4 20°41'45 4937 44°493 44493 4449 44°4 3 44°49'37 9.0 28. 414 204 20° 20°41'4 493 444 44° 44°49'3 9. 20°41' 44°49'

Abstract The productivity of the beef and dairy industries depends directly on the reproductive efficiency and genetic gain of the herd, which are directly associated with the appropriate use of Assisted Reproductive Technologies (ARTs). The objective of this review is to show from a Brazilian perspective the evolution over the last 40 years of ARTs related to ovulation resynchronization programs and embryo transfer in cattle. Despite significant improvements and high fertility obtained in timed artificial insemination (TAI) protocols (Sales et al., 2024 - Part I), the improvement of the use of in vitro-produced embryos, development of resynchronization programs, and the advance in Doppler ultrasonography (Doppler-US) for reproductive assessments of bovine females were the ARTs that presented the greatest relevance on reproductive effectiveness in cattle. In the last seven years, the embryo transfer (ET) technology using in vitro-produced (IVP) embryos took over the conventional ET of in vivo produced embryos after donor’s superovulation. Also, procedures and pregnancy rates after ET of IVP embryos were improved in dairy and beef operations. The Doppler-US allows the identification of non-pregnant females at an early stage based on the evaluation of blood perfusion of the corpus luteum. Recent studies in beef and dairy cows indicate satisfactory accuracy when Doppler-US is used at 20-22 days after TAI. Consequently, super-early resynchronization programs have been developed and are being implemented in commercial programs, thereby facilitating earlier conception through the use of semen from superior bulls, providing genetic and economic improvements in herds. Likewise, the assessment of luteal function by Doppler-US allows the selection of embryo recipients with greater receptivity, and consequently may increase the effectiveness of timed ET programs. herd ARTs. . (ARTs) 4 cattle TAI (TAI Sales al al. 202 I, I , I) vitroproduced vitro DopplerUS US (Doppler-US (ET (IVP donors donor s superovulation Also operations nonpregnant non pregnant luteum 2022 20 22 20-2 Consequently superearly super bulls herds Likewise receptivity (ARTs 2 20-

Abstract This review elucidates the physiological and endocrinological processes intrinsic to puberty and ovulation induction protocols in Bos indicus and Bos taurus beef heifers. Puberty is a complex physiological event involving gonadotropic and metabolic changes that lead to sexual maturity, first ovulation, and regular reproductive cycles, enabling females to reproduce. Exposure to progesterone-based hormonal protocols, with or without additional hormones, can reduce the age at first ovulation and improve sexual maturity through stimuli in the hypothalamus-pituitary-gonadal (HPG) axis and uterine development. However, inducing puberty differs from inducing ovulation, as it does not ensure the heifer will continue cycling or be ready to establish and maintain pregnancy after hormonal exposure. Regardless of the pharmacological basis, studies consistently report that beef heifers that had a corpus luteum (CL) prior to the timed-artificial insemination (TAI) protocol, have greater expression of estrus in response to synchronization and greater pregnancy per AI compared to heifers without a CL. The combination of P4 and E2 significantly impacts uterine development, increasing reproductive efficiency. Exposure to P4 causes a positive effect on inducing ovulation. However, studies indicate that the addition of E2 esters at the time of P4 device removal increases the ovulation rate. In general, the studies showed that fertility varied according to the type of the ovulation induction protocol used, but with inconsistent results. Although ovulation induction protocols are strategic tools to accelerate sexual maturity, a holistic view of the entire system is extremely important, combining integration with genetics and nutrition to enhance the reproductive outcomes of beef heifers. Future research is needed to understand and refine these protocols, driving the efficiency of beef cattle production systems. cycles reproduce progesteronebased progesterone based hormones hypothalamuspituitarygonadal hypothalamus pituitary gonadal HPG (HPG development However exposure basis CL (CL timedartificial timed artificial TAI (TAI P E rate general used results important systems