The effect of Gonadotropin releasing hormone administration on fertility and embryonic loss in goats during the anoestrus period

Following the induction of oestrus out of season in small ruminants, low fertility and variations in fertility rates are associated with embryonic losses. One of the main causes of embryonic loss is luteal dysfunction. Gonadotropin Releasing Hormone (GnRH) supports the luteal structure, and increasing progesterone levels may be beneficial in terms of promoting embryonic life. The main objective of the present study was to evaluate the efficacy of GnRH administration following an oestrus induction protocol in the anoestrus season for preventing embryonic loss in goats having failure to conceive during the season. In the study, 106 Damascus goats aged 3-5 years and weighing 45-60 kg were used. The oestrus of 106 goats in the anoestrous group was stimulated with progesterone and pregnant mare serum gonadotropin (PMSG) treatment. Out of breeding season, goats were divided into the 4 following groups: GnRH0 (n = 27), GnRH7 (n = 26), GnRH0+7 (n = 27) and control (n = 26). In each goat, an intravaginal sponge (IS) containing 20 mg of fluorogestone acetate (FGA) was placed into the vagina and left for 9 days. With the withdrawal of the sponge, 550IU PMSG and 125 µg of d-cloprostenol were injected intramuscularly. Oestrus detection was made via teaser bucks for 3 days starting 24 h after withdrawal of the IS. Eighteen bucks known to be fertile were used for breeding. Goats in the oestrus period were mated via natural breeding. The GnRH analogue lecirelin was injected intramuscularly at breeding in the GnRH0 group, on day 7 post-breeding in the GnRH7 group, and both at breeding and on day 7 post-breeding in the GnRH0+7 group. No injections were given to the control group. Blood samples for progesterone measurement were taken by jugular vena puncturing on days 3, 6, 7, 10, 13, 16, and 19 after breeding from 10 randomly chosen goats in all groups. The goats with a level of > 3.5 ng/mL of progesterone on day 21 post-breeding were evaluated as pregnant. Pregnancy was also viewed on day 50 after breeding by real-time ultrasonography (USG) with a 5-7.5 MHz convex probe. The oestrus rate was 96.23% (102/106) in the goats. The rates of onset of oestrus between 36-48 h, 48-60 h and 60 h and beyond were 38.7% (41/106), 21.7% (23/106) and 35.8% (38/106), respectively. The total pregnancy rate was 35.8% (38/106). There were no statistically significant differences (P > 0.05) found for the pregnancy rate, embryonic death rate or progesterone concentration of the groups. However, serum progesterone levels were statistically different in the GnRH7 group compared with the control group (P < 0.05). After synchronisation, various anti-luteolytic strategies can be used to support corpus luteum development and elevate progesterone concentration in the luteal phase to decrease embryonic loss and increase reproductive performance. Therefore, application of GnRH to support the luteal structure and to increase progesterone levels may be beneficial in terms of supporting embryonic life. The results showed that GnRH treatment on the day 7 post-breeding following oestrus induction, including FGA and PMSG, can increase serum progesterone levels in Damascus goats in the anoestrus period. However, following oestrus induction in the anoestrus period, it was seen that GnRH treatment at breeding or on day 7 after breeding did not have any positive effect on embryonic loss or reproductive performance. In conclusion, it was considered that this protocol could be implemented successfully, yielding a 35% pregnancy rate in Damascus goats in the anoestrus period, but embryonic loss must be deeply studied in detail.(AU)

Different times to perform timed artificial insemination when using a P4/E2/eCG-based protocol in buffalo / Momentos diferentes para executar a inseminação artificial em tempo fixo utilizando o protocolo à base de P4/E2/eCG em búfalas

The aim of this study was to evaluate different times for timed artificial insemination (TAI) in buffalo submitted to a P4/E2/eCG-based protocol. In this study, 204 buffaloes were distributed into one of two groups (TAI56, n=103 and TAI64, n=101). At a random stage of the oestrous cycle (Day 0 = D0), in the morning (TAI56, a.m.) or afternoon (TAI64, p.m.), buffaloes received an intravaginal progesterone device (P4; 1.0 g) plus EB (2.0 mg i.m.). On D9 a.m. (TAI56) or p.m. (TAI64), the P4 was removed and buffaloes received PGF2a (0.53 mg i.m. sodium cloprostenol) and eCG (400 IU i.m.). On D10 a.m. (TAI56) or p.m. (TAI64), 24 h after P4 removal, buffaloes were treated with EB (1.0 mg i.m.). Buffaloes from TAI56 and TAI64 were inseminated 56 and 64 h after P4 removal (D11, p.m. and D12, a.m., respectively). Ultrasound examinations were performed on D0 to ascertain ovarian follicular status, at TAI to measure the diameter of the dominant follicle (DF) and D42 for pregnancy diagnosis. The statistical analysis was performed using the GLIMMIX procedure of SAS®. There was no difference between TAI56 and TAI64 for the diameter of the DF at TAI and the pregnancy per TAI. It was concluded that TAI 56 or 64 h after P4 removal did not affect fertility in buffaloes submitted to the induction of ovulation with EB. The present research supports that is possible to perform TAI at any time throughout the day in buffalo synchronized during the non-breeding season.(AU)

O objetivo deste estudo foi avaliar diferentes momentos para a realização da IATF em búfalas submetidas a um protocolo à base de P4/E2/eCG. Neste estudo, 204 búfalas foram distribuídas em um de dois grupos (IATF56, n=103 e IATF64, n=101). Em estágio aleatório do ciclo estral (Dia 0 = D0), pela manhã (IATF56, manhã) ou pela tarde (IATF64, tarde), as búfalas receberam um dispositivo intravaginal de progesterona (P4; 1,0 g) e BE (2,0 mg i.m.). No D9 pela manhã (IATF56) ou pela tarde (IATF64), a P4 foi removida e as búfalas receberam PGF2a (0,53 mg i.m. cloprostenol sódico) e eCG (400 UI i.m.). No D10 pela manhã (IATF56) ou pela tarde (IATF64), 24 h após a remoção da P4, as búfalas foram tratadas com BE (1,0 mg i.m.). As búfalas dos grupos IATF56 e IATF64 foram inseminadas 56 e 64 h após a remoção da P4 (D11, pela tarde e D12, pela manhã, respectivamente). Avaliações ultrassonográficas foram realizadas no D0 para verificar o status folicular ovariano, na IATF para medir o diâmetro do folículo dominante (FD) e no D42 para o diagnóstico de gestação. A análise estatística foi realizada utilizando o procedimento GLIMMIX do SAS®. Não houve diferença entre os grupos IATF56 e IATF64 no diâmetro do FD na IATF e na prenhez por IATF. Conclui-se que a IATF 56 ou 64 h após a remoção da P4 não afeta a fertilidade de búfalas submetidas à indução da ovulação com BE. A presente pesquisa evidencia que é possível realizar a IATF durante todo o dia em búfalas sincronizadas durante a estação reprodutiva desfavorável.(AU)

Reproductive management of buffalo (Bubalus bubalis) in Italy / Manejo reprodutivo da búfala (Bubalus bubalis) na Itália

Livestock products in tropical areas play a crucial role, which extends beyond their traditional supply of meat and milk. Unprecedented economic growth in developing countries, accompanied by the increases in income and purchasing power and by changes in food preferences, together with the growth of human population, has increased demands on the livestock sector. Livestock products, such as milk and meat, have undergone great modification in response to these recent developments. In Italy, buffalo population has grown from 12 thousand heads in 1947 to 397 thousand in 2017. On the national territory there are 2212 farms concentrated for 74% in the Campania Region, which allow Italy to position itself in the 7th place for the production of fresh buffalo milk in the world, generating an economic induced linked to the Mozzarella di Bufala Campana DOP of 721 million euros for consumption. The Italian Mediterranean buffalo has undergone selection for efficiency of production in intensive dairy systems that aim to achieve milk production throughout the year. Continuous production of buffalo milk is required to meet the market demand for mozzarella cheese and other dairy food products derived from buffalo milk. In the Mediterranean region, female buffaloes show annual fluctuations in reproduction with distinct breeding and nonbreeding seasons. The decline in fertility during the transition from the breeding to nonbreeding seasons is associated with a greater incidence of anestrus, a decline in the function of the CL, and an increase in embryonic mortality Season affects oocyte developmental competence in buffalo, as indicated by higher cleavage and embryo yields recorded in autumn compared to spring, with intermediate results observed in summer and winter. The seasonal characteristic of this species, causes an increase in the phenomenon of embryonic mortality during the periods characterized by increasing daylight length. . In the farms that carry out TAI, absolute or associated with natural mated technique, different plans are used, based on the specific market needs of each farm, on the structures, the management and the reproductive season, preferring protocols such as ovsynch during the period of decreasing daylight length and protocols supported by progesterone during periods of anoestrous. The results obtained in the development and application of the most innovative techniques in the buffalo breeding sector, in synergy with the efficiency of the veterinary information systems, make of Italy a nation at the forefront in the international scene in the breeding techniques and health problems of the buffalo, to which many countries look as a model.(AU)

Reproductive management of buffalo (Bubalus bubalis) in Italy / Manejo reprodutivo da búfala (Bubalus bubalis) na Itália

Livestock products in tropical areas play a crucial role, which extends beyond their traditional supply of meat and milk. Unprecedented economic growth in developing countries, accompanied by the increases in income and purchasing power and by changes in food preferences, together with the growth of human population, has increased demands on the livestock sector. Livestock products, such as milk and meat, have undergone great modification in response to these recent developments. In Italy, buffalo population has grown from 12 thousand heads in 1947 to 397 thousand in 2017. On the national territory there are 2212 farms concentrated for 74% in the Campania Region, which allow Italy to position itself in the 7th place for the production of fresh buffalo milk in the world, generating an economic induced linked to the Mozzarella di Bufala Campana DOP of 721 million euros for consumption. The Italian Mediterranean buffalo has undergone selection for efficiency of production in intensive dairy systems that aim to achieve milk production throughout the year. Continuous production of buffalo milk is required to meet the market demand for mozzarella cheese and other dairy food products derived from buffalo milk. In the Mediterranean region, female buffaloes show annual fluctuations in reproduction with distinct breeding and nonbreeding seasons. The decline in fertility during the transition from the breeding to nonbreeding seasons is associated with a greater incidence of anestrus, a decline in the function of the CL, and an increase in embryonic mortality Season affects oocyte developmental competence in buffalo, as indicated by higher cleavage and embryo yields recorded in autumn compared to spring, with intermediate results observed in summer and winter. The seasonal characteristic of this species, causes an increase in the phenomenon of embryonic mortality during the periods characterized by increasing daylight length. . In the farms that carry out TAI, absolute or associated with natural mated technique, different plans are used, based on the specific market needs of each farm, on the structures, the management and the reproductive season, preferring protocols such as ovsynch during the period of decreasing daylight length and protocols supported by progesterone during periods of anoestrous. The results obtained in the development and application of the most innovative techniques in the buffalo breeding sector, in synergy with the efficiency of the veterinary information systems, make of Italy a nation at the forefront in the international scene in the breeding techniques and health problems of the buffalo, to which many countries look as a model.

Biostimulation in primiparous postpartum acyclic early weaned beef cows: introducing the bulls at weaning advances cyclic rebreeding

Weaning and biostimulation promote an early cyclic postpartum rebreeding. Although the signals and mechanisms by which weaning and biostimulation differ, both end stimulating LH secretion. The aim of the experiment was to determine if weaning and biostimulation have additive effects advancing the postpartum rebreeding in primiparous postpartum anoestrous cows. The experiment was performed during late spring – early summer with 51 primiparous Hereford cows. Six weeks after parturition calves were weaned, and cows were managed in two experimental groups: WB (n = 22) and WDB (n = 29). Bulls were joined with WB cows at weaning, but joining was delayed one week in WDB cows. The presence of corpora lutea in the ovaries was recorded weekly with ultrasound, and 28 and 50 days after the end of the exposure period, pregnancy was determined by ultrasound. The percentage of cyclic cows was greater in WB than in WDB on Weeks 8 (36.4 vs 0 %), 9 68.2 vs 13.8 %), 10 (86.4 vs 27.6 %) and 11 (100.0 vs 37.9 %) (P < 0.001 in all). Cows that were weaned and biostimulated simultaneously rebred earlier than WDB cows (Week 9.1 ± 0.2 vs Week 11.0 ± 0.2; P < 0.0001). At the end of the experiment 46/51 (90.2%) of the animals were cycling. Pregnancy rate tended to be greater in WB than WDB cows 28 days after the end of the breeding period 18/22 vs 17/29, P = 0.077), but there was no difference at the end of the study (20/22 vs 24/29, ns). In conclusion, the application of weaning and biostimulation simultaneously advances postpartum rebreeding more than weaning alone in beef cows.

Biostimulation in primiparous postpartum acyclic early weaned beef cows: introducing the bulls at weaning advances cyclic rebreeding

Weaning and biostimulation promote an early cyclic postpartum rebreeding. Although the signals and mechanisms by which weaning and biostimulation differ, both end stimulating LH secretion. The aim of the experiment was to determine if weaning and biostimulation have additive effects advancing the postpartum rebreeding in primiparous postpartum anoestrous cows. The experiment was performed during late spring early summer with 51 primiparous Hereford cows. Six weeks after parturition calves were weaned, and cows were managed in two experimental groups: WB (n = 22) and WDB (n = 29). Bulls were joined with WB cows at weaning, but joining was delayed one week in WDB cows. The presence of corpora lutea in the ovaries was recorded weekly with ultrasound, and 28 and 50 days after the end of the exposure period, pregnancy was determined by ultrasound. The percentage of cyclic cows was greater in WB than in WDB on Weeks 8 (36.4 vs 0 %), 9 68.2 vs 13.8 %), 10 (86.4 vs 27.6 %) and 11 (100.0 vs 37.9 %) (P < 0.001 in all). Cows that were weaned and biostimulated simultaneously rebred earlier than WDB cows (Week 9.1 ± 0.2 vs Week 11.0 ± 0.2; P < 0.0001). At the end of the experiment 46/51 (90.2%) of the animals were cycling. Pregnancy rate tended to be greater in WB than WDB cows 28 days after the end of the breeding period 18/22 vs 17/29, P = 0.077), but there was no difference at the end of the study (20/22 vs 24/29, ns). In conclusion, the application of weaning and biostimulation simultaneously advances postpartum rebreeding more than weaning alone in beef cows.(AU)

Occurrence of subclinical endometritis in dairy cattle and effect on reproductive efficiency

Background: Subclinical endometritis (SE) have a negative impact on fertility due to an absence of clinical signs which difficult its diagnosis and treatment. The prevalence and impact of the disease on the reproductive status of dairy herds is not known in the region, the objective of the present study was to determine the prevalence of the disease and its effect on the reproductive efficiency in cows of the dairy area from Putumayo State, Colombia.Materials, Methods & Results: Cross-sectional study was made of 166 dairy cows from 30 days postpartum in the municipalities: Santiago, Sibundoy, Colon, and San Francisco. Reproductive evaluation and endometrial cytology were made to establish the SE prevalence determining subsequently the number of open days. Cow whit more than 120 days in milk (DIM) and without confirmed pregnancy was defined as “not reproductive efficiency”. Association between SE and reproductive efficiency was established through Odds Ratio from contingency tables. Bias and confusion control was made through stratified analysis. Results showed 32 cows without changes in reproductive clinical evaluation and inflammatory changes in cytological evaluation (PMNn >5%) for a SE prevalence of 19.27%. Disease occurs most frequently in Colón (23.10%) but the frequency of the disease was not different among the regions (P > 0.05). The group of animals with the greatest days open (DO) mean (161 DIM) had a normal ovarian function and subclinical endometritis. The 6.6% of cows had a poor reproductive prognosis (subclinical endometritis, anestrous and 144 DIM). For the stratified analysis (controlling by anestrus) was estimated the crude OR (OR 5.93; P < 0.05; CI 95% 2.56-14.6) and adjusted ORMH (OR 5.78; P < 0.05; CI 95% 2.39-13.9).[...]

Occurrence of subclinical endometritis in dairy cattle and effect on reproductive efficiency

Background: Subclinical endometritis (SE) have a negative impact on fertility due to an absence of clinical signs which difficult its diagnosis and treatment. The prevalence and impact of the disease on the reproductive status of dairy herds is not known in the region, the objective of the present study was to determine the prevalence of the disease and its effect on the reproductive efficiency in cows of the dairy area from Putumayo State, Colombia.Materials, Methods & Results: Cross-sectional study was made of 166 dairy cows from 30 days postpartum in the municipalities: Santiago, Sibundoy, Colon, and San Francisco. Reproductive evaluation and endometrial cytology were made to establish the SE prevalence determining subsequently the number of open days. Cow whit more than 120 days in milk (DIM) and without confirmed pregnancy was defined as “not reproductive efficiency”. Association between SE and reproductive efficiency was established through Odds Ratio from contingency tables. Bias and confusion control was made through stratified analysis. Results showed 32 cows without changes in reproductive clinical evaluation and inflammatory changes in cytological evaluation (PMNn >5%) for a SE prevalence of 19.27%. Disease occurs most frequently in Colón (23.10%) but the frequency of the disease was not different among the regions (P > 0.05). The group of animals with the greatest days open (DO) mean (161 DIM) had a normal ovarian function and subclinical endometritis. The 6.6% of cows had a poor reproductive prognosis (subclinical endometritis, anestrous and 144 DIM). For the stratified analysis (controlling by anestrus) was estimated the crude OR (OR 5.93; P < 0.05; CI 95% 2.56-14.6) and adjusted ORMH (OR 5.78; P < 0.05; CI 95% 2.39-13.9).[...](AU)

Effect of birth weight and litter size on the performance of landrace gilts until puberty

Background: The selection for larger litter size has resulted in reduction of average birth weight and in increase of withinlitter birth weight variation in pigs. Birth weight is one of the most important factors affecting the survival and performanceof piglets until weaning. The aim of this study was to evaluate the effect of litter size into which gilts were born and theirindividual birth weight on mortality and culling rate until the time of selection, as well as on puberty onset.Materials, Methods & Results: Female Landrace piglets (n = 1525) were identifi ed and weighed within 18 h after birth.They were also weighed at weaning (n = 1379), and at the end of the nursery (n = 1198) and rearing phases (n = 940).Three classes of litter size were created: Small LS (7-11 piglets), Intermediate LS (12-13 piglets) and Large LS (14-19piglets). Gilts were also separated in three classes according to their birth weight: Low BW (530-1200 g), IntermediateBW (1205-1600 g) and High BW (1605-2535 g). When compared to High BW gilts, the risk of death until weaning wasgreater (P < 0.05) in Low BW gilts from Intermediate LS and Large LS litters, but not in Low BW gilts from Small LSlitters. Within the Low BW class, the risk of mortality until weaning was greater or tended to be greater if gilts were bornin Intermediate LS (P < 0.05) or Large LS (P = 0.079) litters compared to those from Small LS litters. Average dailyweight gain (ADWG), and weights at 22, 75 and 155 days of age, increased according to the increase in birth weight(P < 0.05). There was no effect of birth weight or litter size on mortality and culling rate, during nursery and rearing phases,and on percentages of gilts in anoestrous until 30 days after boar stimulation (P > 0.05). The risk of not being selected forbreeding was greater (P < 0.09) in Light BW gilts than in High BW gilts in all litter size classes. Low BW gilts were olderat the beginning...(AU)

IMPACTO DA IATF NA ESTAÇÃO DE MONTA DE FÊMEAS NELORES (BOS TAURUS INDICIUS) COM A UTILIZAÇÃO DA EGG CONSIDERANDO O ECC E O PADRÃO DE CICLICIDADE APÓS TRIAGEM GINECOLÓGICA

O presente trabalho teve como objetivos avaliar a relação custo benefício do emprego da eCG em fêmeas Nelores submetidas à IATF assim como avaliar o impacto dessa biotécnica na eficiência reprodutiva e no peso dos bezerros à desmama durante uma estação de monta. Para tanto, foram utilizadas 347 fêmeas Nelores distribuídas em três grupos: Grupo Controle (GC; n=137), Grupo Experimental 1 (GE1; n=123) e Grupo Experimental 2 (GE2; n=87). A diferença entre os grupos ocorreu nos protocolos de sincronização da ovulação onde o GC não recebeu eCG e os grupos GE1 e GE2 receberam 300UI de eCG. Já a diferença entre os grupos GE1 e GE2 estava relacionada ao padrão de ciclicidade e ao escore de condição corporal dos animais (GE1=cíclicos e/ou ECC 3 e GE2=anestro e/ou ECC <3, escala de 1-5). As taxas de concepção e de prenhez foram analisadas pelo teste qui-quadrado com 5% de significância. As taxas de concepção foram de 59,8%, 63,4% e 41,3%, respectivamente, para os grupos GC, GE1 e GE2, sendo observada diferença estatística (p<0,05) quando comparado o grupo GE2 com os demais grupos. Em relação às taxas de prenhez, os grupos GC, GE1 e GE2 apresentaram os valores de 78,8%, 80,4% e 70,1%, respectivamente, não sendo observada diferença estatística entre os grupos. Conclui se que a utilização da eCG em fêmeas Nelores apresentando boa condição corporal (ECC 3) não interfere nas taxas de concepção, não sendo, economicamente viável sua utilização, porém aumentou a taxa de prenhez em fêmeas apresentando baixa condição corporal (ECC <3) e/ou em anestro (Grupo GE2). Em relação à avaliação do impacto da IATF na eficiência reprodutiva e no peso dos bezerros à desmama, utilizou-se 744 fêmeas Nelores que foram divididas em dois tratamentos: Grupo Monta Natural (MN; n=396), onde os animais ficaram toda a estação de monta apenas com touros e Grupo IATF+MN (n=348), onde, após a realização da IATF, os animais foram colocados em repasse com touro. As taxas de concepção e de prenhez, assim como a eficiência reprodutiva, foram analisadas pelo teste qui-quadrado com 1% de significância. O peso médio dos bezerros à desmama foi analisado pelo ANOVA com 1% de significância. As taxas de concepção para os grupos MN e IATF+MN foram de 56,1% e 56,3%, respectivamente, não sendo observada diferença estatística. Em relação à taxa de prenhez, o grupo MN apresentou 56,1% e o grupo IATF+MN 77,2%, sendo observada diferença estatística. No tocante à eficiência reprodutiva, o grupo MN apresentou 54,8% e o grupo IATF+MN apresentou 75,5%, sendo também observada diferença estatística. E ainda houve diferença estatística no peso dos bezerros à desmama, de maneira que os produtos provenientes da IATF desmamaram 7,59Kg mais pesados quando comparados aos bezerros provenientes da monta natural. Conclui-se que o emprego da IATF, associada ao repasse com touros, possibilita maior taxa de prenhez e melhor eficiência reprodutiva em relação ao uso apenas da monta natural. E ainda que bezerros provenientes da IATF desmamem mais pesados quando comparados aos bezerros de monta natural.

This study aimed to evaluate the cost benefit of eCG in Nellore females submitted to timed artificial insemination (TAI) and also to evaluate the impact of this biotech on reproductive efficiency and weight of calves at weaning during a breeding season. Therefore, 347 Nellore females were divided into three groups: control group (CG, n=137), experimental group 1 (EG1; n=123) and Experimental Group 2 (EG2; n=87). The difference among groups was related to TAI protocols where the CG did not receive eCG and the EG1 and EG2 groups received 300 IU of eCG. However, the difference between EG1 and EG2 groups was related to the pattern of cyclicity and the body condition score (EG1=cycling and/or BCS 3 and EG2=anoestrous and/or BCS <3, range 1-5). The conception and pregnancy rates wer5e analyzed by chi-square test with 5% significance. The conception rates were 59.8%, 63.4% and 41.3%, respectively, for the CG, EG1 and EG2, with statistical difference (p <0.05) for EG2 which conception rate was lower than other groups. Regarding to pregnancy rates, the CG, EG1 and EG2 showed 78.8%, 80.4% and 70.1%, respectively, and there was no statistical difference between groups. It is concluded that the use of eCG in Nellore females showing good body condition (BCS 3) does not interfere in conception rates and is not economically feasible to use, but increased pregnancy rate in females with low body condition (BCS <3) and/or anoestrus (EG2 Group). Regarding to TAI impact assessment on reproductive efficiency and weight of calves at weaning, 744 Nellore females were divided into two treatments: Natural Mating Group (NMG; n=396), where the females were exposed to bulls through all breeding season and TAI+NM Group (n=348), which, after TAI procedure, the animals were exposed to clean-up bull. The conception and pregnancy rates, as well as reproductive efficiency were analyzed by chi-square test with 1% significance. The average weight of calves at weaning was analyzed by ANOVA with 1% significance. The conception rates for NM and TAI+NM groups were 56.1% and 56.3%, respectively, with no statistical difference between groups. Regarding pregnancy rates, the NM group showed 56.1% which was lower (p<0,001) than 77.2% from TAI+NM group. Regarding reproductive efficiency, NM group showed 54.79% and the TAI+NM group showed 75.5%, values that showed statistical difference. And there was also significant difference in the weight of calves at weaning. The weaned calves from TAI were 7,59Kg heavier (p<0,001) than calves from natural mating. It is concluded that the use of TAI, associated with clean-up bulls, enables higher pregnancy rate and better reproductive efficiency comparing to natural mating. In addition, we can conclude that TAI calves weaning heavier when compared to calves from natural mating.

Ovarian follicular dynamics in does on anoestrous period after progestagen treatment / Dinâmica folicular ovariana em cabras em anestro após tratamento progestágeno

Eighteen Anglonubian (n = 9) and Saanen (n = 9) goats were monitored by ultrasonography to characterize the follicular dynamic after induced estrus by progestagen treatment during seasonal anoestrous. In both breeds, the progesterone level reached values above 1.0 ng.ml-1 at D3 and decreased below this value at D18. Among Anglonubian goats, 33.3, 44.5, and 22.2%, respectively, showed two, three and four follicular waves while among Saanen goats 87.5% showed three and 12.5% showed two follicular waves. In both breeds differences among the days of emergence follicular waves, as well among the days that the biggest follicle of each wave reached maximum diameter were detected (P>0.05). In the goats which presented three waves pattern, the emergence day of first, second and third wave occurred at days 2.0 ± 0.9; 9.3 ± 1.4 e 15.1 ± 0.8 versus 1.0 ± 0.5; 6.7 ± 0.9 e 14.6 ± 1.0 in Anglonubian and Saanen, respectively. In the early-mid luteal phase (D8 to D10) the progesterone concentration was higher in four waves goats than two and three waves goats (P

Dezoito cabras Anglonubiana (n = 9) e Saanen (n = 9) foram monitoradas por ultra-sonografia com o objetivo de caracterizar a dinâmica folicular após estro induzido com progestágeno durante anestro estacional. Nas duas raças o nível de progesterona alcançou valores acima de 1,0 ng.mL-1, no D3, e declinou abaixo desse valor, no D18. Entre as cabras Anglonubiana, 33,3%; 44,5 e 22,2% apresentaram, respectivamente, duas, três e quatro ondas, enquanto entre as Saanen, 87,5% apresentaram três e 12,5% duas ondas foliculares. Nas duas raças, foram verificadas diferenças entre os dias de emergência das ondas foliculares e entre os dias em que o maior folículo de cada onda atingiu o diâmetro máximo (P

Ovarian follicular dynamics in does on anoestrous period after progestagen treatment / Dinâmica folicular ovariana em cabras em anestro após tratamento progestágeno

Eighteen Anglonubian (n = 9) and Saanen (n = 9) goats were monitored by ultrasonography to characterize the follicular dynamic after induced estrus by progestagen treatment during seasonal anoestrous. In both breeds, the progesterone level reached values above 1.0 ng.ml-1 at D3 and decreased below this value at D18. Among Anglonubian goats, 33.3, 44.5, and 22.2%, respectively, showed two, three and four follicular waves while among Saanen goats 87.5% showed three and 12.5% showed two follicular waves. In both breeds differences among the days of emergence follicular waves, as well among the days that the biggest follicle of each wave reached maximum diameter were detected (P>0.05). In the goats which presented three waves pattern, the emergence day of first, second and third wave occurred at days 2.0 ± 0.9; 9.3 ± 1.4 e 15.1 ± 0.8 versus 1.0 ± 0.5; 6.7 ± 0.9 e 14.6 ± 1.0 in Anglonubian and Saanen, respectively. In the early-mid luteal phase (D8 to D10) the progesterone concentration was higher in four waves goats than two and three waves goats (P

Dezoito cabras Anglonubiana (n = 9) e Saanen (n = 9) foram monitoradas por ultra-sonografia com o objetivo de caracterizar a dinâmica folicular após estro induzido com progestágeno durante anestro estacional. Nas duas raças o nível de progesterona alcançou valores acima de 1,0 ng.mL-1, no D3, e declinou abaixo desse valor, no D18. Entre as cabras Anglonubiana, 33,3%; 44,5 e 22,2% apresentaram, respectivamente, duas, três e quatro ondas, enquanto entre as Saanen, 87,5% apresentaram três e 12,5% duas ondas foliculares. Nas duas raças, foram verificadas diferenças entre os dias de emergência das ondas foliculares e entre os dias em que o maior folículo de cada onda atingiu o diâmetro máximo (P