Conception rate according to sire, body condition score and estrus occurrence of suckled Bos taurus beef cows submitted to timed artificial insemination / Taxa de concepção de acordo com o touro, escore de condição corporal e ocorrência de estro em vacas de corte Bos taurus lactantes submetidas à inseminação artificial em tempo fixo

The objective of this study was to investigate the effect of estrus expression, body condition score (BCS), different sires and semen batches on the conception rate of suckled Bos taurus beef cows submitted to timed artificial insemination (TAI). Data from 7,737 TAI were obtained from five farms in South Brazil. Cows received an estradiol plus progesterone-based estrous synchronization protocol. Only sires (n = 13) with at least two semen batches and 50 AI in two different lots were included in the study. Conception rate was higher for cows in estrus (66.8% vs. 26.3%) or with BCS ≥ 3 (57.2% vs. 51.6%) than in cows without estrus or BCS < 3, respectively (P≤0.001). Conception rate per sire ranged from 42.6% (Sire L) to 74.3% (Sire K). Conception rate in cows with BCS ≥ 3 and estrus occurrence varied from 47.4% (Sire L) to 86.1% (Sire A) among sires. Conception rate differed among semen batches of the same sire (B1 = 58.5%, B2 = 62.5%, and B3 = 83.2%). In conclusion, there was individual variation in conception rate among AI sires and semen batches within sires. The conception rate was increased by estrus occurrence and greater BCS.

O objetivo deste estudo foi investigar o efeito da manifestação de estro, o escore de condição corporal (ECC), os diferentes touros e partidas de sêmen na taxa de concepção de vacas Bos taurus lactantes de corte submetidas à inseminação artificial em tempo fixo (IATF). Dados de 7.737 IATF foram obtidos em cinco fazendas do sul do Brasil. As vacas receberam um protocolo de sincronização de estro à base de estradiol e progesterona. Somente touros (n=13) com no mínimo duas partidas e 50 inseminações em dois lotes diferentes foram incluídos no estudo. A taxa de concepção foi maior nas vacas em estro (66,8% vs. 26,3%) ou com ECC ≥ 3 (57,2% vs. 51,6%) do que em vacas sem estro ou com menor ECC, respectivamente (P≤0,001). A taxa de concepção por touro variou de 42,6% (Touro L) a 74,3% (Touro K). A taxa de concepção em vacas que demonstraram estro e com ECC ≥3 variou de 47,4% (Touro L) a 86,1% (Touro A) entre os touros. A taxa de concepção diferiu entre partidas de um mesmo touro (B1=58,5%, B2=62,5% e B3=83,2%). Em conclusão, houve variação individual na taxa de concepção entre touros e entre as partidas de sêmen de um mesmo touro. A taxa de concepção foi aumentada pela ocorrência de estro e maior ECC.

Litter decomposition by soil fauna: effect of land use in agroecosystems.

Soil fauna plays a key role in organic matter decomposition. Litter decomposition depends on the relationships of soil fauna and microorganisms as well as climate and litter quality. The decomposer community is sensitive to land use. Thus, physical-chemical disturbances, like soil tillage, can exercise important control on the soil fauna. In order to study the effect of land use and its impact on litter decomposition by soil fauna, a litter-bag experiment was conducted in the Pampa Serrana region, Azul district, Argentina. Litter-bags were made in three different mesh-sizes, allowing the access of micro, micro + meso and micro + meso + macrofauna. Four different treatments were defined: naturalized grassland and three agricultural agroecosystems under different tillage systems, i.e., conservation tillage, conventional-conservation tillage and conventional tillage. Decomposition rate and remaining litter were measured across three different seasons. We found that naturalized grassland obtained the highest decomposition rates and the least remaining litter compared to conservation and conventional tillage systems. No difference in litter decomposition was identified among agricultural agroecosystems. Micro + meso + macrofauna presented the highest decomposition rate and the lowest remaining litter of soil fauna groups, in all agroecosystems. In contrast, microfauna decomposition rate was the lowest and produced the highest remaining litter. Micro + mesofauna presented values of decomposition rate and remaining litter that differed significantly from the rest of the groups in some seasons. These results highlight the importance of soil fauna in litter decomposition and the negative effects of different land use systems on litter decomposition by soil fauna.

Effect of plasma separation techniques and sperm selection on sperm recovery and viability of cooled pony stallion semen for 48h at 5°C / [Efeito das técnicas de separação de plasma e de seleção de esperma na recuperação e viabilidade do sêmen de garanhão pônei resfriado por 48h a 5°C]

Separation techniques of seminal plasma [centrifugation (SC) and Sperm Filter® (SF)] and sperm selection [Androcoll-E (SCA) and filtration glass wool (GW)] were used in 24 ejaculates from 6 stallions. In experiment 1, the ejaculates were allocated into control (no spin), centrifugation at 600 g x 10min, SF and GW. In experiment 2, semen was submitted to SC, SGA and filtered through GW. Following the treatments in both experiments, samples were kept chilled at 5°C to 50 x 106 sperm/ml for 48h. The variables measured on fresh and cooling semen were pH, motility, membrane viability function by 6-carboxyfluorescein diacetate and propidium iodide (CFDA / PI), viability or vitality (eosin / nigrosine) and mitochondrial activity. In experiment 1, centrifugation to remove seminal plasma resulted in greater damage to sperm than separation by sperm filter, and selection by glass wool was more efficient in separating viable cells and maintaining viability during cooling. In experiment 2 Androcoll-E and glass wool treatments resulted in higher (P <0.0001) motility, membrane function, mitochondrial activity, and viability than centrifuged semen. Both selection by Androcoll- E and glass wool improved the quality of semen pony stallions for preservation for up to 48h to 5ºC.(AU)

As técnicas de separação do plasma seminal (centrifugação, SpermFilter) e de seleção espermática (Androcoll-E e filtração por lã de vidro) foram aplicadas em 24 ejaculados de seis garanhões da raça Pônei Brasileiro. Após coleta e separação da fração gel, os ejaculados foram diluídos 1:1 com diluente à base de leite em pó. No experimento 1, os ejaculados foram distribuídos em controle (sem centrifugação), centrifugação a 600g x 10min, SpermFilter e filtração por lã de vidro. No experimento 2, o sêmen foi submetido aos procedimentos: centrifugado (SC), centrifugado com Androcoll-E e filtrado por lã de vidro. Após os procedimentos de ambos os experimentos, as amostras foram mantidas refrigeradas a 5ºC, com 50 x 106 espermatozoides/mL, por 48h. As variáveis mensuradas a fresco, 24h e 48h foram: pH, motilidade, funcionalidade de membrana, viabilidade por diacetato de carboxifluoresceína e iodeto de propídio (CFDA/PI, vitalidade (eosina/nigrosina) e atividade mitocondrial. Já osmolaridade e morfologia espermática foram avaliadas somente imediatamente após a coleta. No experimento 1, a centrifugação para retirada do plasma seminal resultou em maiores danos aos espermatozoides do que a separação por SpermFilter. A filtração por lã de vidro mostrou-se mais eficiente em separar células viáveis e manter a viabilidade durante o resfriamento. No experimento 2, os tratamentos com Androcoll-E e filtrado por lã de vidro foram superiores (P<0,0001) ao sêmen centrifugado quanto à motilidade, à funcionalidade de membrana, à atividade mitocondrial e à viabilidade, tanto nas amostras de sêmen fresco como de sêmen refrigerado. O Androcoll-E e a lã de vidro permitiram manter por 48h, a 5ºC, o sêmen de garanhões pôneis utilizando-se diluente à base de leite.(AU)

Response to cooling of pony stallion semen selected by glass wool filtration.

The aim of this study was to compare the sperm separation technique using filtration through glass wool compared with just diluted cooled semen. Eighteen ejaculates were collected from 6 pony stallions of the Brazilian pony breed. Evaluations were done on pH, osmolarity, total motility, membrane functionality (HOST), membrane integrity (CFDA/PI), morphology and mitochondrial viability (MTT) in fresh, 24 and 48 h of cooled semen at 5°C. After dilution, the half of the extended semen was cooled (control group). The other half was cooled after filtration trough glass wool (filtered group). Retained semen was considered the portion of cells that did not transpose glass wool barrier. Total motility from the control, filtered and retained groups after 24 h of cooling was 35.5%, 43.3% and 10% (p < .0001) respectively. Sperm membrane integrity percentage at the CFDA/PI test was 37.9%, 44.8% and 14.8% (p < .0001), on the control, filtered and retained groups respectively. The results confirmed that the passage of spermatozoa through glass wool increased the selection of spermatozoa from pony stallions with higher motility, mitochondrial viability and membrane integrity for cooling in milk extender up to 24 h. Moreover, it was not obtained higher sperm parameters to control after cooling 48 h under the conditions that the study was conducted.

Bone imaging in hypoparathyroidism.

Hypoparathyroidism (HypoPT) is an uncommon endocrine disorder characterized by chronic deficiency or absence of parathyroid hormone (PTH), which leads to a profound reduction in bone remodeling. Subjects with HypoPT typically have bone mineral densities (BMDs) by dual-energy X-ray absorptiometry (DXA) above average at all skeletal sites, with greatest scores observed at the lumbar spine. Trabecular bone score (TBS), an indirect measure of bone microarchitecture, also appears to be normal in HypoPT. By peripheral quantitative computed tomography (pQCT) of the radius, volumetric BMD at cancellous and cortical compartments, as well as cortical area and thickness, are greater in hypoparathyroid subjects than in controls. The use of high-resolution pQCT (HRpQCT) confirmed the increase in cortical volumetric BMD but demonstrated reduced cortical thickness, associated with lower cortical porosity in HypoPT. Trabeculae tend to be more numerous but thinner in hypoparathyroid subjects. It is not clear whether these structural and the dynamic skeletal abnormalities in HypoPT affect bone strength or fracture risk. Treatment of HypoPT with PTH leads to improvement in bone remodeling rate, variable changes in bone density, and a transient increase in estimated bone strength. The effect of PTH therapy on fracture risk remains unknown. This article reviews skeletal involvement and the effect of PTH treatment in patients with HypoPT, as assessed by DXA, TBS, QCT, and HRpQCT. Data on bone strength and fracture risk in HypoPT are also reviewed here.

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.

The use of PGF2α as ovulatory stimulus for timed artificial insemination in cattle.

The objective of this study was to evaluate the effect of a PGF2α-analogue (PGF) on ovulation and pregnancy rates after timed artificial insemination (TAI) in cattle. In experiment 1, crossbred dual-purpose heifers, in a crossover design (3 × 3), were given an intravaginal progesterone-releasing insert (controlled internal drug release [CIDR]) plus 1 mg estradiol benzoate (EB) intramuscularly (im) and 250 µg of a PGF-analogue im on Day 0. The CIDR inserts were removed 5 days after follicular wave emergence, and the heifers were randomly divided into three treatment groups to receive the following treatments: (1) 1 mg of EB im (EB group, n = 13); (2) 500 µg of PGF im (PG group, n = 13); or (3) saline (control group, n = 13), 24 hours after CIDR removal. Ovulation occurred earlier in EB (69.81 ± 3.23 hours) and PG groups (73.09 ± 3.23 hours) compared with control (83.07 ± 4.6 hours; P = 0.01) after CIDR removal. In experiment 2, pubertal beef heifers (n = 444), 12 to 14 months of age were used. On Day 0, the heifers were given a CIDR insert plus 2 mg EB im. On Day 9, the CIDR was removed and the heifers were given 500 µg of PGF im. Heifers were randomly assigned into one of three treatment groups: (1) 1 mg of EB (EB group; n = 145); (2) 500 µg of PGF (PG group; n = 149), both 24 hours after CIDR removal; or (3) 600 µg of estradiol cypionate (ECP group; n = 150) at CIDR removal. Timed artificial insemination occurred 48 hours after CIDR removal in the ECP group and 54 hours in the PG and EB groups. The percentage of heifers ovulating was higher in the PG group compared with the other groups (P = 0.08). However, the pregnancy rates did not differ among groups (47.6%, 45%, and 46.6%, for EB, PG, and ECP, respectively; P = 0.9). In experiment 3, 224 lactating beef cows, 40 to 50 days postpartum with 2.5 to 3.5 of body condition score were treated similarly as described in experiment 2, except for the ECP group, which was excluded. The treatments were as follows: 1 mg EB (EB group; n = 117) or 500 µg PGF (PG group; n = 107), 24 hours after CIDR removal. The calves were temporarily separated from their dams from Days 9 to 11. No difference was detected on the pregnancy rate between the EB and PG groups (58.1% vs. 47.6%, respectively; P = 0.11). Taken together, the combined results suggested that PGF2α could be successfully used to induce and synchronize ovulation in cattle undergoing TAI, with similar pregnancy rates when compared with other ovulatory stimuli (ECP and EB).

Maternal serum progesterone, estradiol and estriol levels in successful dinoprostone-induced labor.

Hormone-mediated quiescence involves the maintenance of a decreased inflammatory responsiveness. However, no study has investigated whether labor induction with prostanoids is associated with changes in the levels of maternal serum hormones. The objective of this study was to determine whether labor induction with dinoprostone is associated with changes in maternal serum progesterone, estradiol, and estriol levels. Blood samples were obtained from 81 pregnant women at term. Sixteen patients had vaginal birth after spontaneous labor, 12 required cesarean section after spontaneous labor and 16 underwent elective cesarean. Thirty-seven patients had labor induction with dinoprostone. Eligible patients received a vaginal insert of dinoprostone (10 mg) and were followed until delivery. Serum progesterone (P4), estradiol (E2) and estriol (E3) levels and changes in P4/E2, P4/E3 and E3/E2 ratios were monitored from admission to immediately before birth, and the association of these measures with the resulting clinical classification outcome (route of delivery and induction responsiveness) was assessed. Progesterone levels decreased from admission to birth in patients who underwent successful labor induction with dinoprostone [vaginal and cesarean birth after induced labor: 23% (P < 0.001) and 18% (P < 0.025) decrease, respectively], but not in those whose induction failed (6.4% decrease, P > 0.05). Estriol and estradiol levels, P4/E2, P4/E3 and E3/E2 ratios did not differ between groups. Successful dinoprostone-induced labor was associated with reduced maternal progesterone levels from induction to birth. While a causal relationship between progesterone decrease and effective dinoprostone-induced labor cannot be established, it is tempting to propose that dinoprostone may contribute to progesterone withdrawal and favor labor induction in humans.

Maternal serum progesterone, estradiol and estriol levels in successful dinoprostone-induced labor

Hormone-mediated quiescence involves the maintenance of a decreased inflammatory responsiveness. However, no study has investigated whether labor induction with prostanoids is associated with changes in the levels of maternal serum hormones. The objective of this study was to determine whether labor induction with dinoprostone is associated with changes in maternal serum progesterone, estradiol, and estriol levels. Blood samples were obtained from 81 pregnant women at term. Sixteen patients had vaginal birth after spontaneous labor, 12 required cesarean section after spontaneous labor and 16 underwent elective cesarean. Thirty-seven patients had labor induction with dinoprostone. Eligible patients received a vaginal insert of dinoprostone (10 mg) and were followed until delivery. Serum progesterone (P4), estradiol (E2) and estriol (E3) levels and changes in P4/E2, P4/E3 and E3/E2 ratios were monitored from admission to immediately before birth, and the association of these measures with the resulting clinical classification outcome (route of delivery and induction responsiveness) was assessed. Progesterone levels decreased from admission to birth in patients who underwent successful labor induction with dinoprostone [vaginal and cesarean birth after induced labor: 23% (P < 0.001) and 18% (P < 0.025) decrease, respectively], but not in those whose induction failed (6.4% decrease, P > 0.05). Estriol and estradiol levels, P4/E2, P4/E3 and E3/E2 ratios did not differ between groups. Successful dinoprostone-induced labor was associated with reduced maternal progesterone levels from induction to birth. While a causal relationship between progesterone decrease and effective dinoprostone-induced labor cannot be established, it is tempting to propose that dinoprostone may contribute to progesterone withdrawal and favor labor induction in humans.

Prostaglandin F2α promotes ovulation in prepubertal heifers.

The objective was to determine the effects of exogenous prostaglandin F(2α) (PGF), with or without progesterone treatment, on first ovulation in prepubertal heifers. We tested the hypothesis that PGF has a luteolysis-independent ovulatory effect in cattle. Crossbred Angus heifers (12 to 14 mo old, 250 kg body weight, and an average body condition score of 3 out of 5) were examined by transrectal ultrasonography on two occasions, 11 days apart. Heifers in which a CL was not detected at either examination were considered prepubertal. Heifers were assigned randomly to three experimental groups: (1) PG group (N = 14); heifers were treated with a PGF analog (500 µg cloprostenol im) 5 days after the emergence of a spontaneous (i.e., naturally occurring, noninduced) follicular wave; (2) PPG group (N = 12); heifers were given an intravaginal progesterone-releasing insert (CIDR; Pfizer Animal Health, Montreal, QC, Canada), and a follicular wave was induced with 50 mg of progesterone + 2 mg of estradiol benzoate im, and a PGF analog was given at the time of CIDR removal, on day 5 of the follicular wave (on average, 8.6 ± 0.5 days after CIDR insertion); and (3) control group heifers were given no treatment (N = 14). Heifers were examined daily by transrectal ultrasonography from the start of the experiment to confirmation that ovulation had occurred, or to 5 days after PGF injection (PG and PPG groups) or until dominant follicles of the next follicular wave reached 8 mm (control group). The percentage of heifers that ovulated within 10 days after wave emergence was higher in PPG (10/12; 83.3%) and PG (11/14; 78.5%) groups than in control (1/14; 7.1%; P < 0.0001). Ovulations occurred 69.6 ± 6 h and 93.8 ± 5 h after PGF treatment in PPG and in PG groups, respectively, whereas only one heifer in the control group ovulated 96 h after day 5 of follicular wave (P = 0.13). In summary, PGF treatment was associated with ovulation in prepubertal heifers whether or not exogenous progesterone was used as a pretreatment. The hypothesis that PGF will induce ovulation by a luteolysis-independent mechanism was supported.

Involvement of the glutamatergic system in the nociception induced intrathecally for a TRPA1 agonist in rats.

The transient receptor potential ankyrin 1 (TRPA1) is expressed in peripheral and spinal terminals of sensory neurons, jointly to the vanilloid receptor (TRPV1). A relevant peripheral role of TRPA1 receptor has been implicated in a variety of processes, including the detection of noxious cold, and diverse painful stimulus, but the functional role of TRPA1 receptor in nociceptive transmission at spinal cord in vivo is poorly known. Therefore, the aim of this study was to evaluate whether the glutamatergic system is involved in the transmission of nociceptive stimulus induced for a TRPA1 agonist in the rat spinal cord. We observed that cinnamaldehyde, a TRPA1 agonist, on spinal cord synaptosomes leads to an increase in [Ca(2+)](i) and a rapid release of glutamate, but was not able to change the specific [(3)H]-glutamate binding. In addition, spinally administered cinnamaldehyde produced heat hyperalgesia and mechanical allodynia in rats. This behavior was reduced by the co-injection (i.t.) of camphor (TRPA1 antagonist) or MK-801 (N-methyl-D-aspartate (NMDA) receptor antagonist) to cinnamaldehyde. Besides, the pretreatment with resiniferatoxin (RTX), a potent TRPV1 agonist, abolished the cinnamaldehyde-induced heat hyperalgesia. Here, we showed that intrathecal RTX results in a decrease in TRPA1 and TRPV1 immunoreactivity in dorsal root ganglion. Collectively, our results demonstrate the pertinent participation of spinal TRPA1 in the possible enhancement of glutamatergic transmission of nociceptive signals leading to increase of the hypersensitivity, here observed as heat hyperalgesia. Then the modulation of spinal TRPA1 might be a valuable target in painful conditions associated with central pain hypersensitivity.

Progesterone production in mares and echographic evaluation of the corpora lutea formed after follicular aspiration.

Ultrasound-guided follicular aspiration was performed in 26 Criollo crossbred mares, followed by the evaluation of ultrasonographic images of the Corpus luteum (CL) that was formed after puncture of follicles of different diameters (Group 25-29 mm; Group 30-35 mm and Group >35 mm). Serum progesterone (P(4) ) concentrations were measured to determine CL function. The size of the CL was measured and the CL was classified based on the following echoscore: 1- anechoic tissue; 2- poorly defined luteal structure with low echogenicity; 3- echogenicity analogous to a luteal structure. The proportion of aspirated follicles that formed a functional CL (based on P(4) concentration) 8 days after aspiration was 57.1% (4/7; CL size 25-29 mm), 75.0% (6/8; CL size 30-35 mm) and 72.7% (8/11; CL size >35 mm), respectively (p > 0.05). The echographic scores of aspirated follicles (indicating the presence or absence of a CL) were consistent with serum P(4) concentrations (p < 0.0001). Of 26 aspirations, 18 resulted in luteal function confirmed by increased progesterone concentrations ([P(4) ] > 1.0 ng/ml); 17 of these mares (94.4%) had an echoscore (2-3) compatible with luteinization (p = 0.0372). Eight days after aspiration, serum [P(4) ] > 2.0 ng/ml was associated with high (p = 0.0056) CL echoscore (3) in 15 of 17 mares (88.2%). The echoscore used in this study was valuable as a screening test to detect the presence of a functional CL after aspiration. An echoscore of 3 served as a practical and efficient method to confirm luteinization.

Qualidade do leite em amostras individuais e de tanque de vacas leiteiras

Bovine milk samples were collected from milk tanks (n = 69) and from individual cows (n = 3,517) on specialized (S, n = 3), partially specialized (PS, n = 5) and nonspecialized (NS, n = 7) production systems. Compositions, somatic cell count (SCC) and urea nitrogen content were analyzed for the different production systems and all the four seasons. Data were compared to the ranges allowed by the Federal Normative Instruction 51/2002 (IN51) for South Brazil from May 2009 to June 2010. Forty-two percent (n = 29/69) of all milk samples obtained from tanks and 11% of the individual samples in the three production systems met IN51 standards. Of the collected tank samples, 70% (n = 14/20), 39% (n = 9/23) and 23% (n = 6/26) of the S, PS and NS systems, respectively, met IN51 criteria. These data indicate that evaluation of individual samples yields a lower percent of conformity with IN51 standards than tank samples. This implies that the milk from healthy cows may dilute the higher SCC of diseased cows, suggesting that tank samples are not accurate for a confident milk quality indicator. The fat, protein and total solids content in the tank samples were similar among the three production systems. Average lactose and urea nitrogen content in tank samples were similar between seasons. In contrast, the average SCC was above the IN51 standard in the tank and individual samples during the fall. Urea nitrogen content average was highest (P 0.001) in the specialized production system, both in the tank and individual samples. The evaluation of individual samples may improve nutritional support of the specialized system.

Amostras de leite foram coletadas de tanques de expansão (n = 69) e das vacas individualmente (n = 3517), em propriedades com sistema de produção especializado (ES, n = 3), semiespecializado (SE, n = 5) e não especializado (NE, n = 7). A composição, contagem de células somáticas (CCS) e teor de nitrogênio ureico (NU) foram avaliados nos diferentes sistemas e estações do ano. Os dados foram comparados aos parâmetros da Instrução Normativa 51/2002 (IN51) para a região Sul do Brasil, de maio/2009 a junho/2010. Analisando os três sistemas de produção, 42% (n = 29/69) das amostras de leite dos tanques de expansão e 11% (n = 375/3517) das individuais atenderam a IN51. Amostras de leite de tanque do sistema ES 70% (n = 14/20), SE 39% (n = 9/23) e NE 23% (n = 6/26) atenderam os critérios da IN51. Amostras de leite individuais apresentaram menor percentual com parâmetros mínimos da IN51 comparada ao tanque. O leite de vacas sadias dilui a CCS de vacas doentes, indicando que a CCS do tanque não é um indicador confiável para qualidade do leite. Os teores médios de gordura, proteína e sólidos totais em amostras de tanque foram semelhantes entre os sistemas de produção. A lactose e NU nas amostras do tanque foram similares entre as estações do ano. Em contraste, a CCS do tanque e individual não alcançaram os parâmetros da IN51. O teor médio de NU foi maior (P 0,001) nas amostras de leite de tanque e individual do sistema especializado. A análise de amostras de leite de cada vaca permitiu melhoria nutricional do rebanho especializado.

Estimate of the population of preantral follicles in the ovaries of Bos taurus indicus and Bos taurus taurus cattle.

The number of oocytes recovered from Bos taurus indicus females subjected to ovum pick-up averaged two to four times greater compared to Bos taurus taurus females. The objective of the present study was to test the hypothesis that this difference in oocyte yield was due to more preantral follicles in the ovaries of Bos indicus females. Ovaries (n = 64) from Nelore (Bos indicus) fetuses (n = 10), heifers (n = 12), and cows (n = 10), and Aberdeen Angus (Bos taurus) fetuses (n = 10), heifers (n = 12), and cows (n = 10) were cut longitudinally into halves, fixed, and processed for histological evaluation. The number of preantral follicles was estimated by counting them in each histological section, using the oocyte nucleus as a marker and employing a correction factor. The average number of preantral follicles in the ovaries of Bos indicus vs Bos taurus was (mean ± SD) 143,929 ± 64,028 vs 285,155 ± 325,195 for fetuses, 76,851 ± 78,605 vs 109,673 ± 86,078 for heifers, and 39,438 ± 31,017 vs 89,577 ± 86,315 for cows (P > 0.05). The number of preantral follicles varied greatly among individual animals within the same category, as well as between breeds. In conclusion, we inferred that the higher oocyte yield from Bos indicus females was not due to a greater ovarian reserve of preantral follicles. Therefore, mechanisms controlling follicle development after the preantral stage likely accounted for differences between Bos indicus and Bos taurus females in number of oocytes retrieved at ovum pick-up.

Increased expression of growth differentiation factor-15 in systemic sclerosis-associated pulmonary arterial hypertension.

BACKGROUND: Growth differentiation factor (GDF)-15 is a secreted member of the transforming growth factor-ß cytokine superfamily. GDF-15 levels are elevated in the serum of patients with cardiovascular diseases. We hypothesized that GDF-15 levels would also be increased in the plasma and lung tissue of patients with systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH). METHODS: GDF-15 levels were measured in plasma in subjects with SSc-PAH (n = 30) and compared with subjects with systemic sclerosis (SSc) without pulmonary arterial hypertension (PAH) (n = 24). Patients with idiopathic PAH (IPAH) (n = 44) and normal individuals (n = 13) served as control subjects. Immunohistochemistry and immunofluorescence assay identified GDF-15 protein in lung tissue from patients with SSc-PAH and IPAH. RESULTS: Patients with SSc-PAH had significantly higher mean circulating levels of GDF-15 in plasma compared with patients with SSc without PAH (422.3 ± 369.5 pg/mL vs 108.1 ± 192.8 pg/mL, P = .004). GDF-15 levels correlated positively with estimated right ventricular systolic pressure on echocardiogram and plasma levels of the amino terminal propeptide form of brain natriuretic peptide. There was an inverse correlation between circulating GDF-15 and diffusing capacity of the lung for carbon monoxide (Dlco) and a positive correlation with the FVC to Dlco ratio on pulmonary function test. GDF-15 levels > 125 pg/mL were associated with reduced survival. GDF-15 protein expression was increased in lung tissue from patients with SSc-PAH. CONCLUSIONS: GDF-15 may be a useful biomarker in PAH associated with SSc. Its presence in lung tissue may suggest a role in the pathology of the disease.

Fetal calf serum enhances in vitro production of Bos taurus indicus embryos.

The objective of this study was to determine the effect of fetal calf serum (FCS) on the quality of in vitro produced bovine embryos. Cumulus oocyte-complexes (COCs, n = 2 449) recovered by ovum pick-up from Bos taurus indicus donors were randomly assigned to experimental groups. Sperm selected by Percoll gradient was used for in vitro fertilization (insemination = Day 0). In Experiment 1 (n = 1 745 COCs), zygotes were cultured in vitro in Synthetic Oviduct Fluid + 4 mg/mL of bovine serum albumin (BSA), or BSA + 2% FCS (BSA+FCS). In Experiment 2 (n = 704 COCs), the COCs were cultured in SOF + BSA, BSA + 2% FCS, or BSA + 2% FCS on D4 (BSA + FCSD4). In Experiment 1, blastocyst yield (51%) and Quality I blastocysts (41%) at Day 7 were higher (P < 0.05) in the BSA + FCS treatment than in BSA (42 and 30%, respectively). In Experiment 2, blastocyst yield was higher (P < 0.05) in the BSA+FCS (47%) treatment. Quality I blastocyst yield was higher (P < 0.05) for BSA + FCS (34%) and BSA+FCSD4 (32%) compared to the BSA treatment (20%). A total of 820 embryos were transferred, with no significant differences among groups in pregnancy rates. In conclusion, in vitro culture in SOFaaci + BSA + FCS enhanced blastocyst yield and Quality I blastocysts; adding FCS to the culture medium increased the efficiency of IVP of bovine embryos.

Influence of climatic conditions on in vitro production of bovine embryos / Influência do clima na produção in vitro de embriões bovinos

Temperature and rainfall were analyzed daily during six years to evaluate their influence on in vitro production of bovine embryos. Weekly replications (n=480) were performed on 14,778 ovaries collected at slaughterhouses. Cumulus oocyte complexes (n=19,180) were fertilized with a pool of Bos taurus taurus semen in one incubator with 5 percent CO2. Presumable zygotes were cultured in gasified plastic bags with 5 percent CO2, 5 percent O2, and 90 percent N2. In the first year, cleavage and embryo yield were 60.3 percent and 15.6 percent, respectively, being lower (P<0.05) than in the following years. Average cleavage rates were always lower in winter (P<0.0001), thus producing less embryos. Winter climatic conditions had a negative influence on in vitro production, when cleavage and embryo yield declined, possibly because of reduced availability and growth of native pasture.(AU)

A temperatura e a precipitação pluviométrica foram analisadas diariamente, durante seis anos, para avaliar sua influência sobre a produção in vitro de embriões bovinos. As repetições semanais (n=480) foram realizadas com 14.778 ovários coletados em matadouros. Os oócitos (n=19.180) foram maturados em estufa com atmosfera com controle de temperatura e umidade saturada com 5 por cento de CO2 e, após 20h, foram fecundados com sêmen de Bos taurus taurus e mantidos sob as mesmas condições de atmosfera da maturação. Os zigotos foram cultivados em placas de quatro poços em bolsas gaseificadas com 5 por cento de CO2, 5 por cento de O2 e 90 por cento de N2, à temperatura de 39ºC e umidade saturada. No primeiro ano, a taxa clivagem (60,3 por cento) e a produção de embriões (15,6 por cento) foram inferiores (P<0,05) aos demais anos. As taxas de clivagem foram sempre menores no inverno (P<0,0001). As condições climáticas no inverno tiveram influência negativa sobre a produção in vitro de embriões bovinos e houve diminuição nos índices de clivagem e produção de blastocistos, possivelmente devido à reduzida disponibilidade e crescimento da pastagem nativa.(AU)

Influence of climatic conditions on in vitro production of bovine embryos / Influência do clima na produção in vitro de embriões bovinos

Temperature and rainfall were analyzed daily during six years to evaluate their influence on in vitro production of bovine embryos. Weekly replications (n=480) were performed on 14,778 ovaries collected at slaughterhouses. Cumulus oocyte complexes (n=19,180) were fertilized with a pool of Bos taurus taurus semen in one incubator with 5 percent CO2. Presumable zygotes were cultured in gasified plastic bags with 5 percent CO2, 5 percent O2, and 90 percent N2. In the first year, cleavage and embryo yield were 60.3 percent and 15.6 percent, respectively, being lower (P<0.05) than in the following years. Average cleavage rates were always lower in winter (P<0.0001), thus producing less embryos. Winter climatic conditions had a negative influence on in vitro production, when cleavage and embryo yield declined, possibly because of reduced availability and growth of native pasture.

A temperatura e a precipitação pluviométrica foram analisadas diariamente, durante seis anos, para avaliar sua influência sobre a produção in vitro de embriões bovinos. As repetições semanais (n=480) foram realizadas com 14.778 ovários coletados em matadouros. Os oócitos (n=19.180) foram maturados em estufa com atmosfera com controle de temperatura e umidade saturada com 5 por cento de CO2 e, após 20h, foram fecundados com sêmen de Bos taurus taurus e mantidos sob as mesmas condições de atmosfera da maturação. Os zigotos foram cultivados em placas de quatro poços em bolsas gaseificadas com 5 por cento de CO2, 5 por cento de O2 e 90 por cento de N2, à temperatura de 39ºC e umidade saturada. No primeiro ano, a taxa clivagem (60,3 por cento) e a produção de embriões (15,6 por cento) foram inferiores (P<0,05) aos demais anos. As taxas de clivagem foram sempre menores no inverno (P<0,0001). As condições climáticas no inverno tiveram influência negativa sobre a produção in vitro de embriões bovinos e houve diminuição nos índices de clivagem e produção de blastocistos, possivelmente devido à reduzida disponibilidade e crescimento da pastagem nativa.

Luteal function induced by transvaginal ultrasonic-guided follicular aspiration in mares.

Ultrasonic-guided transvaginal follicle aspiration was performed in 58 crossbreed mares in order to determine whether aspiration of various dominant follicle diameters resulted in luteal tissue capable of producing progesterone (P(4)). The mares were randomly assigned to three groups according to follicular diameter (25-29 mm; 30-35 mm and >35 mm). Mares that had ovulations naturally served as controls. The serum progesterone (P(4)) concentrations in the aspirated mares were greater (P < 0.0001; r(2) = 0.6687; CV = 21.52) in mares with natural ovulation compared to mares with aspirated follicles regardless of groups. Serum P(4) concentration in aspired mares with follicular diameter of 25-29 mm declined 0.365 ng/ml/day (P = 0.0065) from the day of aspiration (D0) up to D8. In mares with follicle diameter of 30-35 mm, serum P(4) concentration increased (0.258 ng/ml/day; P = 0.001), as well as in the mares with follicles >35 mm diameter (0.481 ng/ml/day; P < 0.0001), and in mares with natural ovulation (1.236 ng/ml/day; P < 0.0001). Out of the 25 mares with follicular aspirations that formed Corpora hemorragica (P(4) >1 ng/ml), 23 (92%) had greater (>2 ng/ml) serum P(4) concentrations on Day 8 after aspiration. Of these 23 mares, 75% were in the 25-29 mm group, 9/10 (90%) in the 30-35 mm group, and 11/11 (100%) of the mares in the >35 mm follicular diameter group had luteinization (P(4) >2 ng/ml). These results suggest that a functional Corpus luteum can be induced in mares using follicular aspiration and that a minimum 35 mm follicular diameter is needed to reach a progesterone serum concentration compatible with that of a Corpus luteum produced by natural ovulation.