Occurrence Of Estrus Research Articles

Pre-pubertal treatment with a GnRH agonist in bitches-Effect on the uterus and hormone receptor expression.

Aim of the study was to examine the effect of deslorelin on uterine tissues of eleven pre-pubertal bitches aged 4.2±0.6m. Implants containing placebo (sodium chloride 0.9%; n=4, G I), 4.7mg (n=3, GII) or 9.4mg (n=4, GIII) deslorelin acetate (Suprelorin® ; Virbac, France), were administered subcutaneously. Signs of oestrus, vaginal cytology, serum progesterone (P4) and estradiol-17β (E2) concentrations were monitored until the occurrence of oestrus. Bitches were ovariohysterectomized and sections from the uterine tissue were subjected to immunohistochemistry (IHC) for detection of GnRH receptor (R), Kisspeptin (KP)10, Kisspeptin receptor (GPR54), androgen receptor (AR), oestrogen receptor (ER) α,β, and progesterone receptor (PR). Tissue sections were scored semi-quantitatively using an immunoreactivity score (IRS) ranging from 0 to 300 (3). Since some animals were ovariohysterectomized before puberty (n=1 from GII and n=2 from GIII), and some in metestrus (all controls and 2 from GII and GIII each), results from these animals were separately evaluated and compared to the controls. Results: No abnormalities were seen in uterine tissues. Kisspeptin 10 expression was low in all cell types, highest IRS were seen in the vascular endothelial cells. The GPR54 was mainly detected in the luminal epithelial cells, superficial and deep uterine glands. The expression of GPR54 and ERα,β was especially high in bitches operated prepubertally. No difference was observed between the controls and experimental bitches operated in their first metestrus. The PR and ERα,β were exclusively expressed in superficial and deep uterine glands and luminal surface epithelial cells. The AR and GnRH-R expression was negative in all cells of all groups. We conclude that application of 4.7 or 9.4mg deslorelin at the age of 4months did not cause uterine disturbances. GPR54 expression might be influenced by pre-pubertal deslorelin treatment or the changings related to approaching puberty; the latter is supposed in case of ERα,β.

Effect of immunocastration on growth performance, gonadal development and carcass and meat quality of SuHuai female pigs

The present study was aimed to compare growth performance, gonadal development, carcass characteristic and meat quality among SuHuai entire, immunocastrated and surgically castrated female pigs. Eighty 12-week-old SuHuai gilts were randomly assigned to the following four treatment groups with four pigs per pen and five replicate pens per treatment: control (PBS injection), two-dose Improvac regimen (V2), three-dose Improvac regimen (V3) and surgical castration (S). All pigs had ad libitum access to standard diets and water. The performance and occurrence of oestrus were recorded in the trial. Backfat thickness and loin eye muscle area were recorded ultrasonically. The pigs were slaughtered to measure the weight and size of the uterus, and the weight and activity of the ovaries, to determine the serum concentrations of progesterone, and to evaluate the quality of carcass and meat. There were no significant differences in growth performance among the four groups, except for the V2, which had a better average daily feed intake (P < 0.05). Carcass and meat quality were comparable among the four groups; however, the intramuscular fat in control was higher than the V2 and V3 (P < 0.01). Mean ovary and uterus weights and oestrus of female pigs in V2 and V3 were significantly (P < 0.01) lower than in control, but the difference between the V2 and V3 was not significant. The concentration of progesterone in the control was significantly higher than that in the V2, V3 and S (P < 0.05). These results indicated that immunocastration successfully suppressed gonadal development and had no adverse effects on growth performance, or carcass or meat-quality traits in Chinese SuHuai female pigs.

Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season.

The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n=24; 34.72±0.52kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4-dimethylamino-2-methyl-phenyl-phosphonate as an organic bound phosphorous twice a week for successive 3weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30days post-service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks -2, -1, 0 (mating day) and + 4weeks post-oestrus. Phosphorus group had significantly (p<.05) short interval to oestrous resumption if compared to control ewes (2.1±0.8weeks vs. 4.6±1.1weeks). In addition, phosphorous supplementation significantly (p<.05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72±0.3mm vs. 7.46±0.9mm) as well. Number of services per conception (2.6 vs. 1.4; p<.01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs. 50%) was significantly (p<.01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8±0.44; p<.05) and monocytes (2.93±0.13; p<.01) were higher than that of control group (white blood cells; 9.53±0.50 and monocytes; 2.24±0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.

Effect of climate and insemination technique on reproductive performance of gilts and sows in a subtropical zone of Mexico

ABSTRACT: The objective of this study was to analyse the reproductive performance of hybrid (Yorkshire x Landrace) gilts/ sows in relation to temperature-humidity index (THI) at artificial insemination (AI), season of AI, occurrence of estrus >8 d post- weaning, repeated estrus, insemination technique (cervical, CAI or post-cervical, PCAI) and parity. Data included 8851 reproductive records (1771 for gilts and 7080 for sows) from a pig farm in a sub-tropical zone (THI ranged from 72.9 in January to 81.8 in June). A decrease in pregnancy rate (PR, 89.8 vs 93.0%; P 82), compared to AI at 8 d. The insemination technique did not affect PR and FR but the litter size decreased (P<0.05) from 11.3 ± 3.0 to 11.1 ± 2.9 pigs when PCAI was used compared to CAI. This study reaffirms the negative effects of the hot season on reproductive performance of gilts/sows, although thermal stress at AI did not cause foetal losses. Also, there is no advantage in using the PCAI as compared to the CAI in gilts/sows with high numbers of sperm cells per AI.

A software tool for the automatic and real-time analysis of cow velocity data in free-stall barns: The case study of oestrus detection from Ultra-Wide-Band data

The increase in the design and utilisation of real-time location systems has produced a huge amount of data to be handled in real time. As a consequence, challenges still exist in improving the analysis process of data streams by designing new tools. In this context, a software tool for automatic and real-time analysis of cow velocity data acquired by an ultra-wide band real-time location system (UWB RTLS) in a free-stall barn was designed and developed. A functionality implemented in this software determined the instant velocity of each cow over time, which was represented through an interactive graph (CowVelocityGraph). Feasibility of the software tools for the visualisation and analysis of UWB data was assessed. A use case of this software tool was carried out to verify its suitability to acquire useful information related to the occurrence of cow's oestrus, which is the case study of this research. The results showed that a pattern, related to the behaviour of the cow analysed, could be identified in CowVelocityGraph when the state of oestrus occurred, allowing for visualisation and analysis of UWB data. The software developed in this study provides the user with the ability to work in real time by acquiring the RTLS data updated at short time intervals, greatly exploiting the UWB RTLS potentialities. Further tests need to be repeated in different farming conditions, on a significant number of cows. On a broader perspective, this study addressed the lack of analysis tools for data streams acquired in livestock houses.

Impact of hormonal modulation at proestrus on ovarian responses and uterine gene expression of suckled anestrous beef cows

BackgroundThis study evaluated the impact of hormonal modulation at the onset of proestrus on ovarian response and uterine gene expression of beef cows.MethodsA total of 172 anestrous beef cows were assigned to one of four groups according to the treatment with estradiol cypionate (ECP) and/or equine chorionic gonadotropin (eCG) [CON (n = 43), ECP (n = 43), eCG (n = 44) and ECP + eCG (n = 42)].ResultsECP-treated cows (ECP and ECP + eCG groups) presented greater occurrence of estrus (44.6% vs. 65.4%; P = 0.01) and pregnancy per AI [47.1% vs. 33.3%; P = 0.07], but similar progesterone (P4) concentration at subsequent diestrus than cows not treated with ECP (CON and eCG groups). Nonetheless, eCG-treated cows (eCG and ECP + eCG groups) presented larger follicle at timed AI (12.6 ± 0.3 vs. 13.5 ± 0.3 mm; P = 0.03), greater ovulation rate (96.5% vs. 82.6%; P = 0.008) and greater P4 concentration at d 6 (3.9 ± 0.2 vs. 4.8 ± 0.2 ng/mL; P = 0.001) than cows not treated with eCG (CON and ECP groups). Next, cows with a new corpus luteum 6 d after TAI were submitted to uterine biopsy procedure. Uterine fragments [CON (n = 6), ECP (n = 6)] were analyzed by RNA-Seq and a total of 135 transcripts were differentially expressed between groups (73 genes up-regulated by ECP treatment). Subsequently, uterine samples were analyzed by qPCR (genes associated with cell proliferation). ECP treatment induced greater abundance of PTCH2 (P = 0.07) and COL4A1 (P = 0.02), whereas suppressed EGFR (P = 0.09) expression. Conversely, eCG treatment increased abundance of HB-EGF (P = 0.06), ESR2 (P = 0.09), and ITGB3 (P = 0.05), whereas it reduced transcription of ESR1 (P = 0.05). Collectively, supplementation with ECP or eCG at the onset of proestrous of anestrous beef cows influenced ovarian responses, global and specific endometrial gene expression. ConclusionProestrus estradiol regulate the endometrial transcriptome, particularly stimulating proliferative activity in the endometrium.

Synchronization of estrus in paca (Cuniculus paca L.): possible impacts on reproductive and productive parameters

A sincronização é uma biotécnica reprodutiva que melhora a porcentagem de cobertura por meio da manipulação do ciclo estral. Empregar esta biotécnica em pacas de cativeiro (Cuniculus paca L.) é importante, pois cria-se a expectativa de que a demanda pela carne seja atendida e a caça ilegal diminua. O objetivo da pesquisa foi verificar o efeito de implantes de progestágenos associados a duas doses de gonadotrofina coriônica equina (eCG) na sincronização e indução de cios férteis de pacas. Foram utilizadas 18 fêmeas não prenhas e nove machos, divididos em três grupos. Fêmeas do G1 e G2 receberam implantes com 1,5mg de Norgestomet e, sete dias depois, 0,13mg de prostaglandina via intramuscular (IM). No dia 8 (D8), foram retirados os implantes e G1 e G2 receberam 25 UI e 50 UI de eCG, IM, respectivamente; G3 foi o controle. O pareamento nos três grupos aconteceu nos mesmos dias. As fêmeas do G3 apresentaram cio alguns dias após o dia zero (D0). Fêmeas que receberam tratamento apresentaram cio só após a retirada do implante no dia 8 (D8). As taxas de prenhez de G1, G2 e G3 atingiram 100%, 66% e 50%, respectivamente. Em relação a filhotes por parto, 100% do G1 e G3 produziram uma cria, enquanto 50% do G2 produziram duas crias. O progestágeno do implante foi eficaz em mimetizar a fase lútea do ciclo estral. Após a remoção, o tratamento hormonal favoreceu a ocorrência de cio fértil. Outros estudos devem ser realizados a fim de estabelecer uma possível associação entre 50 UI de eCG e a ocorrência de gestações gemelares.

Progesterone (P4), luteinizing hormone (LH) levels and ovarian activity in postpartum Santa Inês ewes subject to a male effect

Abstract. This study aimed to establish P4 and luteinizing hormone (LH) levels and ovarian activity as approaches to monitor the cyclicity of ewes under postpartum anestrus after the male effect approach. Santa Inês females (n = 66) were evenly distributed into experimental groups where they were brought into contact with an intact male during the postpartum period of 35 to 40 days (T1) and 55 and 60 days postpartum (T2). Ewes were isolated from males for 30 days before the onset of the experiment. Estrus events were detected in 93.30 % (T1) and 100 % (T2) of females. Mean P4 concentrations (η g mL−1) before and after mating were 0.53 ± 0.17 and 4.55 ± 0.24 (T1) and 0.73 ± 0.06 and 4.90 ± 0.11 (T2), respectively, and concentrations were found to be lower (P &lt; 0.05) before contact between genders. Preovulatory peaks of LH (η g mL−1) were evaluated at 42 (T2) and at 80 h (T1) after exposure to males, with mean ovulatory follicles of 7.90 ± 0.31 (T1) and 8.50 ± 0.30 mm (T2) and a mean number of ovulations of 1.50 ± 0.54 (T1) and 1.60 ± 0.51 (T2). Pregnancy rates were 85.70 % (T1) and 93.3 % (T2), with no difference (P &gt; 0.05) between groups. Results showed that the male effect was effective for inducing and concentrating the occurrence of estrus in postpartum ewes that had lambed within 35 to 60 days previously. Moreover, preovulatory LH peaks occurred within 80 h after physical contact between genders, which led to follicle luteinization and increased P4 concentration, without compromising pregnancy rates. The male effect can be used with postpartum ewes that had lambed within 35 to 40 days previously in order to decrease time between deliveries.

Characteristics of Cervical Mucus for Estrus Detection in Murrah Buffaloes (Bubalus bubalis)

The objective of the experiment was to study the changes in different characteristics of cervical mucus of Murrah buffaloes in relation to occurrence of estrus. The Murrah buffaloes maintained at Livestock Research Centre (LRC), ICAR-NDRI, Karnal were classified into three groups viz. heifers, primipara and pluripara. Cervical mucus was collected on the day of estrus prior to the artificial insemination by aspiration from the mid cervix using blue sterile sheath and Universal artificial insemination gun through recto-vaginal method. Immediately after collection, mucus sample was taken to the laboratory various physical and chemical parameters were assessed. From the present study it can be concluded that the changes in cervical mucus characteristics can be used for prediction of estrus time and subsequently time of artificial insemination. Murrah buffaloes exhibited higher proportion (70%) of copious discharge, 86% buffaloes had clean appearance and 68% of buffaloes showed moderate consistency of cervical mucus. The spinnbarkeit value of cervical mucus of 46% of estruses were in 8–16 cm and 58% showed the typical fern pattern predominantly with primary, secondary and tertiary venation. pH of cervical mucus were within 7.5–8.0 and conductivity in a range of 13.50–15.00 mS/cm.

Increasing estrus expression in the lactating dairy cow

Using an activity monitoring system (AMS) equipped with an accelerometer, 2 experiments were conducted to test the hypotheses that (1) enhancing progesterone before inducing luteolysis or (2) exposing cows to estradiol cypionate (ECP) or testosterone propionate (TP) after luteolysis would increase occurrence and intensity of estrus. Our goal was to determine if more cows could be detected in estrus by an AMS compared with other estrus-detection aids. In experiment 1, cows (n=154) were fitted with both an AMS collar and a pressure-sensitive, rump-mounted device (HeatWatch; HW) and assigned to 3 treatments: (1) no CL + progesterone insert (CIDR) for 5d, (2) CL only, or (3) CL + 2 CIDR inserts for 5d to achieve a range in concentrations of progesterone. Prostaglandin F2α was administered to all cows upon CIDR insert removal or its equivalent. Progesterone concentration up to 72h posttreatment was greatest in CL + 2 CIDR, followed by CL only, and no CL + CIDR cows. Estrus occurred 14 to 28h earlier in no CL + CIDR compared with CL-bearing cows. Estrus intensity was greater for CL + 2 CIDR than for CL-only cows. The AMS and HW detected 70 and 59% of cows defined to be in estrus, respectively. In experiment 2, cows (n=203) were equipped with both an AMS and a friction-activated, rump-mounted patch (Estrotect patch) and assigned to receive 1mg of ECP, 2mg of TP, or control 24h after PGF2α. Concentrations of estradiol 24 and 48h after treatment were greater in ECP cows compared with controls. Estrus expression detected by AMS or patches in cows defined to be in estrus tended to be greater or was greater for ECP compared with controls, respectively. Compared with controls and in response to TP or ECP, estrus occurred 8 to 18h earlier and was of greater intensity for ECP cows, respectively. The AMS and patches determined 73 and 76% of cows defined to be in estrus, respectively. Of cows exposed to the AMS, HW, or patches, 70, 61, and 75%, respectively, were detected in estrus and more than 93% of these subsequently ovulated. In contrast, of the residual cows not detected in estrus, 62 to 77% ovulated in the absence of detected estrus. Only ECP was successful in inducing more expression and intensity of estrus, and proportions of cows detected in estrus exceeded 80%. Given the large proportion of cows equipped with AMS collars ovulating in the absence of estrus, further research is warranted to determine if more pregnancies can be achieved by inseminating those cows not detected in estrus at an appropriate time when PGF2α is administered to induce luteolysis.

Changes of locomotion activity in the Holstein dairy cows during estrus

The objective of this study was the evaluation of the locomotion activity in heifers and Holstein dairy cows during estrus. We have analysed the locomotion activity using the Heatime RuminAct device on 99 dams (68 dairy cows and 31 heifers) and we evaluated a total of 213 estrus cycles during the reference period of 3 days before estrus, 3 days after estrus and on the day of the estrus occurrence. The data was analysed using the DataFlow TM II program. The locomotion of cows was expressed in the units of locomotion activity in 24 hours (u/24h). During the reference period, 3 days before estrus the cows showed locomotion activity 602.7 u/24h, with an increase in the locomotion activity on the day of estrus of 876 u/24h and during the reference period 3 days after estrus the level of locomotion activity decreased to 566 u/24h, what is the similar locomotion activity to the reference period before estrus.

Occurrence of Postpartum Estrus under Different Lactations and Agro Climatic Seasons in Holstein-Friesian Upgraded Cows

Occurrence of Postpartum Estrus under Different Lactations and Agro Climatic Seasons in Holstein-Friesian Upgraded Cows

Different doses of equine chorionic gonadotropin on ovarian follicular growth and pregnancy rate of suckled Bos taurus beef cows subjected to timed artificial insemination protocol

This study evaluated the effect of different doses of eCG (control, 300 or 400 IU) administered at progesterone (P4) device removal in suckled Bos taurus beef cows undergoing a timed artificial insemination (TAI) protocol. A total of 966 cows received a P4 insert and 2.0 mg intramuscular estradiol benzoate at the onset of the synchronization. After 9 days, P4 insert was removed, and 12.5 mg of dinoprost tromethamine and 1 mg of estradiol cypionate were administered, followed by TAI 48 hours later. Then, the cows received one of three treatments as follows: control (n = 323), 300 (n = 326), or 400 IU of eCG (n = 317). A subset (n = 435) of cows in anestrus had their ovaries evaluated using ultrasound at the time of P4 removal and at TAI. Data were analyzed by orthogonal contrasts (C): C1 (eCG effect) and C2 (eCG dose effect). Estrous occurrence (control = 53.7%, 300 IU = 70.6%, and 400 IU = 77.0%) and pregnancy per artificial insemination (control = 29.7%, 300 IU = 44.8%, and 400 IU = 47.6%) were improved by eCG treatment (C1; P = 0.0004 and P < 0.0001, respectively). Furthermore, the cows receiving eCG presented larger follicles at TAI (control = 13.5 ± 0.3 mm, 300 IU = 14.0 ± 0.2 mm, and 400 IU = 15.1 ± 0.3 mm; P < 0.0001; C1). However, there was no effect of eCG dose on any response variables studied (C2; P > 0.15). In conclusion, the eCG treatment administered at the time of P4 removal increased the occurrence of estrus, the larger follicles at TAI, and pregnancy per artificial insemination of suckled B taurus beef cows. Despite the greater occurrence of estrus in noncyclic cows receiving 400 IU of eCG, both eCG doses (300 and 400 IU) were equally efficient to improve pregnancy to artificial insemination.

Effects of light pollution on seasonal estrus and daily rhythms in a nocturnal primate

Mammals use variations in the length of day to anticipate environmental changes and time their reproduction. Light pollution, which affects day length perception, could lead to changes in biological functions. To explore the effects of light pollution on seasonal reproduction, we conducted an experimental study on a strict long-day breeder, the nocturnal gray mouse lemur (Microcebus murinus). Twelve females were randomly exposed to either a moonlight treatment or a light pollution treatment for 5 weeks during the transition from a short- to long-day photoperiod. Daily rhythms of locomotor activity and core temperature were recorded, and the occurrence of estrus and urinary 17-β-estradiol concentrations were monitored. In females exposed to light pollution, the first seasonal estrus occurred while they were still in a short-day photoperiod, 2 weeks earlier than in females exposed to moonlight. Moreover, the daily rhythms profiles of females exposed to light pollution showed significant changes that mimicked long-day acclimatization. This study demonstrates that light pollution can affect daily rhythms and the timing of seasonal estrus in a primate and suggests that functional changes in the circadian system may underlie the adverse effects of light pollution that are observed in wildlife.

Using Estrus-Detection Patches to Vary Time of Insemination Improves Pregnancy Rates Compared with One Single Timed Insemination

Timed artificial insemination (TAI) of beef cows at a predetermined time is a management tool that reduces labor costs associated with conventional heat detection before insemination. Multiple research trials have examined timing of the individual components of the developed protocols associated with TAI. The 7-day CO-Synch + progesterone insert (controlled internal drug release; CIDR) protocol has been shown to initiate ovulation effectively in cycling and noncycling suckled beef cows, often producing pregnancy rates greater than 50% in beef cows. In the current research, we examined using two targeted insemination intervals depending on the occurrence of estrus. We hypothesized that by more closely synchronizing estrus and insemination that pregnancy rates would be increased. We further hypothesized that cows that do not demonstrate estrus and are subjected to a TAI protocol might benefit from an increased interval to insemination.

Estrus response and fertility rate in Kundhi buffaloes following estrus synchronization in breeding season

The aim of the present study was to compare the effect of two estrus synchronization treatments i.e. , Ovsynch alone and Ovsynch plus Controlled Internal Drug Release (CIDR), on the occurrence of estrus and conception rate in Kundhi buffalo during breeding season in Pakistan. Forty Kundhi buffaloes were randomly selected and were divided into three groups; Group A (n=16; Ovsynch) received 2 mL GnRH intramuscularly (i/m) on day 0 and 9. On day 7, 5 mL prostaglandin F2α (PGF2α analogue) was administered through i/m route. The buffaloes of Group B (n=17; Ovsynch+CIDR) received 2 mL GnRH on day 0 along with implantation of CIDR. On day 7, the CIDR was removed, and 5 mL PGF2α analogue was injected through i/m route. A second dose of GnRH was administered through i/m route after 48 h of PGF2α inj. in both groups. Group C (n=7; control) received 2 mL normal saline through i/m route on day 0, 7 and 9. The buffaloes of all three groups were artificially inseminated twice (12 h and 24 h after the second GnRH inj.) using frozen-thawed semen. Estrus response differed significantly ( P< 0.05) among the groups. The animals of Group B (76.47%) showed superior estrus response as compared to others. Higher conception rate (52.94%) was observed in the animals of Group B; however, the difference was not significant. In conclusion, Ovsynch+CIDR causes to occur better estrus response and conception rate as compared to Ovsynch alone in Kundhi buffaloes during breeding season. http://dx.doi.org/10.5455/javar.2015.b97

Plasma micronutrients status and gonadotrophin hormone profiles during peripubertal period in female Black Bengal goat

The aim of the study was to address the micronutrients’ status and hormonal profiles and their relationships during the sexual maturity in Indian prolific Black Bengal goats. Female Black Bengal kids (12) were selected at day 1 of age and subjected to the weekly blood samplings from the day 1 age up to 8 weeks post puberty. Live body weight was recorded weekly. The occurrence of estrus was checked by a teaser buck, followed by transrectal ultrasonographic (USG) examination on 10th day post puberty. Plasma samples harvested from the blood samples were assayed for progesterone to detect luteal function and confirm the timing of puberty onset. The female Black Bengal goats attained puberty at an average age of 25.47±3.84 weeks with a mean body weight of 7.93±0.87 kg. The plasma samples were further utilized for estimating zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), follicle stimulating hormone (FSH) and luteinizing hormone (LH). Plasma Zn, Fe and FSH levels increased during the months preceding puberty onset. Plasma Cu and Mn levels remained higher during the month of puberty. The significant correlations of body weight with plasma FSH, LH, Cu, Zn and Mn levels and between micronutrients and gonadotrophin hormones before puberty onset might have important functions of micronutrients and gonadotrophin hormones for bringing about puberty onset in prolific Black Bengal goats.

Manifestation of estrous behavior and subsequent progesterone concentration at timed-embryo transfer in cattle are positively associated with pregnancy success of recipients

Plasma estradiol and progesterone (P4) concentrations during the peri-ovulatory period are positively correlated with pregnancy success in cattle. The aims of this study were to assess the effects of estrus occurrence and early diestrus P4 concentrations on pregnancy per timed-embryo transfer (P/TET). A total of 267 crossbred beef heifers [222 with corpus luteum (CL) and 45 without a CL but with a follicle >8mm at beginning of the estrous synchronization protocol) received an intra-vaginal P4 device and intramuscular administration of estradiol benzoate. Progesterone devices were removed 8 days later (Day 0), and heifers received d-cloprostenol, eCG and estradiol cypionate. Estrous behavior was monitored twice daily for 3 days after P4 device removal. Plasma P4 concentration was measured by radioimmunoassay at Day 7 and Day 9. At Day 9, heifers with a CL (n=236; i.e. submission rate of 85.5%; 236/276) undergoing TET received an in vitro-produced embryo. Heifers expressing a standing behavioral estrus had a greater P/TET than heifers that did not express a standing estrus [62.4% (106/170) compared with 47.0% (31/66)]. The probability of pregnancy was positively correlated with plasma P4 concentration at TET. When heifers were grouped by quartiles of P4 concentration at TET (Q1=0.64±0.16, Q2=1.70±0.04, Q3=2.90±0.07 and Q4=5.52±0.27ng/mL) the P/TET were 45.8% (Q1; 27/59)c, 52.25% (Q2; 31/59)bc, 66.1% (Q3; 39/59)ab and 67.8% (Q4; 40/59)a. Additionally, heifers that became pregnant had greater P4 concentrations at TET (2.87±0.16ng/mL; n=137) than heifers that did not become pregnant (2.45±0.24ng/mL; n=99). No statistical difference was observed regarding P4 concentrations on Day 7, regardless of standing estrus or pregnancy status. In cattle, manifestation of estrous behavior and plasma P4 concentration at TET increase the probability of pregnancy in in vitro-produced embryo recipients.

A 25years experience of group-housed sows-reproduction in animal welfare-friendly systems.

Since January 1 2013, group housing of sows has been compulsory within the European Union (EU) in all pig holdings with more than ten sows. Sows and gilts need to be kept in groups from 4 weeks after service to 1 week before the expected time of farrowing (Article 3(4) of Directive 2008/120/EC on the protection of pigs). The legislation regarding group housing was adopted already in 2001 and a long transitional period was allowed to give member states and producers enough time for adaptation. Even so, group housing of sows still seems to be uncommon in the EU, and is also uncommon in commercial pig farming systems in the rest of the world. In this review we share our experience of the Swedish 25 years of animal welfare legislation stipulating that sows must be loose-housed which de facto means group housed. The two most important concerns related to reproductive function among group-housed sows are the occurrence of lactational oestrus when sows are group-housed during lactation, and the stress that is associated with group housing during mating and gestation. Field and clinical observations in non-lactating, group-housed sows in Sweden suggest that by making basic facts known about the pig reproductive physiology related to mating, we might achieve application of efficient batch-wise breeding without pharmacological interventions. Group housing of lactating sows has some production disadvantages and somewhat lower productivity would likely have to be expected. Recordings of behavioural indicators in different housing systems suggest a lower welfare level in stalled animals compared with group-housed ones. However, there are no consistent effects on the reproductive performance associated with different housing systems. Experimental studies suggest that the most sensitive period, regarding disturbance of reproductive functions by external stressors, is the time around oestrus. We conclude that by keeping sows according to the pig welfare-friendly Directive 2008/120/EC, it is possible to combine group-housing of sows with good reproductive performance and productivity. However, substantially increased research and development is needed to optimize these systems.

OVARIAN RESPONSE OF DAIRY COWS TO PROGESTERONE COMBINED ON

The objective of this study was to evaluate the response of ovaries in estrus synchronizationprotocol using GnRH-PGF2α based protocol combined progestin in a herd with tie-stall housing system.A total of 20 Holstein Friesian cows at different stages of estrus cycle in a dairy herd were enrolled inthe present study. The cows were randomly allocated into two treatment groups; with and without CIDR(Controlled internal drug release) insertion. All cows received 100 μg of GnRH I.M. at the beginning ofthe treatment (d 0) without regard to the stages of the estrus cycle followed by 25 mg PGF2α IM 7dayslater. Cows in CIDR group were inserted CIDR into the vagina at the time of GnRH administration andwere removed on the day of PGF2α administration. estrus signs were checked twice daily starting onday-2 after initiation of the protocol, except cows in CIDR group the estrus signs were checked startingon day-8 of the protocol. The animals showing estrus signs were noted. Blood samples were collectedfrom all animals on the days of GnRH and PGF2α treatments and on day-10 after initiation of protocolfor progesterone concentration. The results of this study showed that 30% animals in cows withoutCIDR insertion showed estrus signs prior to PGF2α injection. Involving CIDR to synchronized estruswith GnRH-PGF2α based protocol avoided the occurrence of premature estrus and maintained highprogesterone concentration on the day of PGF2α administration. It is concluded that ovarian responseafter involving CIDR in the protocol for estrus synchronization especially using combination of GnRHand PGF2α were much effective to synchronize the initiation of estrus in dairy cows. Likewise, the useof progesterone avoided premature estrus.