An NBS-LRR protein in the Rpp1 locus negates the dominance of Rpp1-mediated resistance against Phakopsora pachyrhizi in soybean.

The soybean Rpp1 locus confers resistance to Phakopsora pachyrhizi, causal agent of rust, and resistance is usually dominant over susceptibility. However, dominance of Rpp1-mediated resistance is lost when a resistant genotype (Rpp1 or Rpp1b) is crossed with susceptible line TMG06_0011, and the mechanism of this dominant susceptibility (DS) is unknown. Sequencing the Rpp1 region reveals that the TMG06_0011 Rpp1 locus has a single nucleotide-binding site leucine-rich repeat (NBS-LRR) gene (DS-R), whereas resistant PI 594760B (Rpp1b) is similar to PI 200492 (Rpp1) and has three NBS-LRR resistance gene candidates. Evidence that DS-R is the cause of DS was reflected in virus-induced gene silencing of DS-R in Rpp1b/DS-R or Rpp1/DS-R heterozygous plants with resistance partially restored. In heterozygous Rpp1b/DS-R plants, expression of Rpp1b candidate genes was not significantly altered, indicating no effect of DS-R on transcription. Physical interaction of the DS-R protein with candidate Rpp1b resistance proteins was supported by yeast two-hybrid studies and in silico modeling. Thus, we conclude that suppression of resistance most likely does not occur at the transcript level, but instead probably at the protein level, possibly with Rpp1 function inhibited by binding to the DS-R protein. The DS-R gene was found in other soybean lines, with an estimated allele frequency of 6% in a diverse population, and also found in wild soybean (Glycine soja). The identification of a dominant susceptible NBS-LRR gene provides insight into the behavior of NBS-LRR proteins and serves as a reminder to breeders that the dominance of an R gene can be influenced by a susceptibility allele.

Climatic seasons and time of the day influence thermoregulation and testicular hemodynamics in Santa Inês rams raised under humid tropical conditions.

This study evaluated the possible association between the diurnal variations of climatic factors during the rainy (RS) or less rainy (LS) seasons on the testicular hemodynamics and thermoregulatory responses of hair sheep rams raised in a humid tropical climate. Santa Inês rams (n = 6) underwent evaluation of general and testicular physiological parameters (heart and respiratory rates, internal and scrotal temperatures, internal-scrotal temperature gradient, scrotal distention, and color Doppler ultrasound evaluation of the spermatic cords and spectral analyses of testicular arteries) over six consecutive weeks per season at three separate times daily (morning = 8:00 a.m., noon = 12:00 p.m., and afternoon = 5:00 p.m.) during the RS and LS. Climatic air temperature and relative humidity data were recorded, and the temperature and humidity index (THI) was calculated. Higher thermal challenge was observed in LS relative to RS (air temperature = 28.0 vs. 30.9 °C; relative humidity = 84.1 vs. 69.9%; THI = 80.0 vs. 82.5; P < 0.05). In both seasons, respiratory rate and internal temperature were normal, demonstrating the animals' adaptability. In RS, however, a higher scrotal temperature was recorded in relation to LS (35.0 vs. 34.7 °C; P < 0.05), with a gradual increase from morning to afternoon. Lower resistivity (0.40 vs. 0.64; P < 0.05) and pulsatility (0.55 vs. 1.14; P < 0.05) indices, and a higher rate of high-velocity blood flow of testicular arteries (71.1 vs. 60.6%; P < 0.05) were observed in RS compared to LS. The lowest correlations between testicular hemodynamic, physiological variables, and environmental parameters (P < 0.05) were observed in the morning. In conclusion, testicular thermoregulation and testicular hemodynamics were influenced by the climatic seasons and time of the day, being more efficient in the LS season and with less interference from environmental factors in the morning.

Growth and transpiration of soybean genotypes with HaHB4® transcription factor for drought tolerance.

The expression of HaHB4® transcription factor reduces soybean sensitivity to abiotic stresses, such as water deficit. Studies that quantify the tolerance of HaHB4® soybean to the soil water content in comparison with cultivars currently sown in Brazil are lacking. The objective of this study was to determine the level of drought tolerance of soybean genotypes expressing the HaHB4® transcription factor (TS18-6-610108 and TS18-6-610084) and commercial cultivars (TMG 7063 IPRO and BS IRGA 1642 IPRO) subjected to water deficit during the vegetative phase. We used the fraction of transpirable soil water (FTSW) approach. Parameters related to leaf transpiration, dry matter accumulation, water use efficiency (WUE), and transpiration coefficient (TC) were evaluated in the four soybean genotypes and two treatments (T1-100% replacement of transpired water and T2-without replacement of transpired water). The FTSW threshold for the decline in transpiration was evaluated to identify the onset of water stress in soybean. TS18-6-610108 and BS IRGA 1642 IPRO maintains potential transpiration at low FTSW values. The TS18-6-610108 genotype has 14% higher WUE than the sensitive cultivar under water deficit. Under well-irrigated conditions, the HaHB4® genotypes showed the highest TC values, which indicate well-functioning physiological processes.

Study of the factors affecting embryo yields and quality in superovulated Morada Nova ewes that underwent non-surgical uterine flushing.

The present study compared the outcomes of in vivo embryo production in Morada Nova ewes subjected to either 9-day (G-9SOV , n = 21) or 12-day (G-12SOV , n = 21) progesterone (P4 )-based estruses synchronization protocol coupled with superovulatory treatment with decreasing doses of porcine follicle-stimulating hormone (133 mg of pFSH given over 3 days). Non-surgical embryo recovery (NSER) was performed 6-7 days after the onset of oestrus. Total antral follicle count doubled from the first to the sixth pFSH dose in both groups (p < .05). Oestrus responses did not vary between the two groups of animals (95.2%). Corpora lutea (CL) were detected in 85.0% and 60.0% of ewes that previously manifested oestrus behaviour in G-9SOV and G-12SOV respectively. NSER was successfully completed in 86.2% of ewes that had CL (p > .05). The mean number of CL per ewe/successfully flushed donor ewe was greater (p < .05) in G-12SOV (12.3 ± 1.7/12.1 ± 1.9) than in G-9SOV (7.9 ± 1.4/8.2 ± 1.6). Mean numbers of retrieved blastocysts and viable embryos were greater (p > .05) in G-12SOV (5.8 ± 1.9 and 3.7 ± 1.7) than G-9SOV (3.5 ± 1.1 and 0.8 ± 0.3 respectively). The total follicle count (all follicles ≥2 mm in diameter) at the sixth pFSH dose (at P4 -device removal) was positively correlated (p < .05) with the number of CL (r = .95) and viable embryos (r = .91) in G-12SOV . The ewes with ≥10 Cl (48% of all flushed donors) yielded 80.5% of viable embryos. In summary: (a) Morada Nova ewes from G-12SOV group had better superovulatory responses compared with G-9SOV group; (b) total follicle count at the last pFSH dose was a good predictor of superovulatory responses only in the ewes primed with P4 for 12 days; and (c) animals with ≥10 ovulations are main contributors to viable embryo production in Morada Nova ewes.

Major differences between single or twin hair lambs in the immediate postpartum period: Metabolic and thermodynamic patterns detected by infrared thermography.

The objective was to evaluate the differences between hair lambs, born from single or twin births, regarding the latency periods for standing up and suckling, the vitality, glycemic, cortisol, and triiodothyronine concentrations, as well as the phenotypic characteristics related to the maintenance of homeothermy in the immediate postpartum. Single (n = 10) or twin (n = 12) Morada Nova lambs were evaluated after birth, during the first successful suckling (M0 = Timepoint 0), and at regular intervals of 20 min (M20, M40, M60). Lambs from single births had higher birth weight (3.09 vs 2.58 kg; P ≤ 0.05) and higher serum triiodothyronine concentration (267 vs 209 ng/dL; P ≤ 0.05) compared to twin lambs. There was a positive correlation between weight and blood glucose (0.57; P ≤ 0.05) for both single and twin lambs. The type of birth did not affect vitality, which was negatively associated with cortisol concentration (-0.53; P ≤ 0.05). Twin lambs had higher internal and ocular temperatures (39.29 vs 38.67 °C and 38.84 vs 38.13 °C; P ≤ 0.05, respectively). Body surface temperatures increased over time in both groups (P ≤ 0.05). An increase in the temperature of the hips region (ysingle = 27.88 + 0.019*time; R2 = 0.96; P = 0.019 and ytwin = 28.74 + 0.019*time; R2 = 0.94; P = 0.029) was observed for both single and twin lambs, which coincides with the region of brown adipose tissue deposition. The lowest absolute thermal variabilities between twin and single lambs in M0 and M60 were recorded in the midloin and integral dorsal area. The parturition type did not influence the latencies to stand up (P = 0.908) and for the first suckling (P = 0.888), and the vitality score (P = 0.353). Thus, single and twin lambs do not differ in neonatal behavior, but they presented specific metabolic strategies to regulate body temperature over time. Midloin and integral dorsal areas are anatomical regions suggested for use in serial thermographic monitoring. Infrared thermography may be an important complementary resource in neonatal care.

Paracoccidioidomycosis due to P lutzii: The importance of neutrophil/lymphocyte ratio in the symptomatic and asymptomatic phases in severe cases.

BACKGROUND: PCM is a neglected systemic mycosis endemic in Brazil. The middle-west region of Brazil has shown the highest number of PCM by Paracoccidioides lutzii (P lutzii) cases. Differentiating cases of severe PCM from non-severe ones should be a concern at the bedside. Diagnosis of severe PCM by P lutzii is based on the subjectivity of clinical manifestations, which can result in a delay in starting its treatment and, consequently evolution to severe sequelae. There is not laboratory biomarker available to support the early diagnosis of severe PCM that is feasible for all the realities that coexist in Brazil. OBJECTIVES: The aim of this study was to investigate the usefulness of laboratory biomarkers as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and neutrophil/lymphocyte ratio (NLR) in the diagnosis of severe PCM. PATIENTS/METHODS: ESR, CRP and NLR were analysed for 44 patients with PCM by P lutzii and a Receiver Operation Characteristic (ROC) curve were generated to identify the NLR cut-off point and point out the presence of severe PCM. RESULTS: Sixteen (36.4%) had severe PCM and 28 (63.6%) had non-severe PCM. The mean NLR was higher and statistically significant among patients with severe PCM than among those with non-severe PCM. The area under the ROC curve was 0.859 for the diagnosis of severe PCM. The cut-off point for NLR for the diagnosis of severe PCM was 3.318 (sensitivity of 100%, specificity of 77%). CONCLUSIONS: According to results, it is plausible to conclude that NLR represents a potential biomarker for the diagnosis of severe PCM.

Environmental enrichment and exercise are better than social enrichment to reduce memory deficits in amyloid beta neurotoxicity.

Recently, nongenetic animal models to study the onset and development of Alzheimer's disease (AD) have appeared, such as the intrahippocampal infusion of peptides present in Alzheimer amyloid plaques [i.e., amyloid-ß (Aß)]. Nonpharmacological approaches to AD treatment also have been advanced recently, which involve combinations of behavioral interventions whose specific effects are often difficult to determine. Here we isolate the neuroprotective effects of three of these interventions-environmental enrichment (EE), anaerobic physical exercise (AnPE), and social enrichment (SE)-on Aß-induced oxidative stress and on impairments in learning and memory induced by Aß. Wistar rats were submitted to 8 wk of EE, AnPE, or SE, followed by Aß infusion in the dorsal hippocampus. Short-term memory (STM) and long-term memory (LTM) of object recognition (OR) and social recognition (SR) were evaluated. Biochemical assays determined hippocampal oxidative status: reactive oxygen species, lipid peroxidation by thiobarbituric acid reactive substance (TBARS) test, and total antioxidant capacity by ferric reducing/antioxidant power (FRAP), as well as acetylcholinesterase activity. Aß infusion resulted in memory deficits and hippocampal oxidative damage. EE and AnPE prevented all memory deficits (STM and LTM of OR and SR) and lipid peroxidation (i.e., TBARS). SE prevented only the SR memory deficits and the decrease of total antioxidant capacity decrease (i.e., FRAP). Traditionally, findings obtained with EE protocols do not allow discrimination of the roles of the three individual factors involved. Here we demonstrate that EE and physical exercise have better neuroprotective effects than SE in memory deficits related to Aß neurotoxicity in the AD model tested.

BeamLearning: An end-to-end deep learning approach for the angular localization of sound sources using raw multichannel acoustic pressure data.

Sound source localization using multichannel signal processing has been a subject of active research for decades. In recent years, the use of deep learning in audio signal processing has significantly improved the performances for machine hearing. This has motivated the scientific community to also develop machine learning strategies for source localization applications. This paper presents BeamLearning, a multiresolution deep learning approach that allows the encoding of relevant information contained in unprocessed time-domain acoustic signals captured by microphone arrays. The use of raw data aims at avoiding the simplifying hypothesis that most traditional model-based localization methods rely on. Benefits of its use are shown for real-time sound source two-dimensional localization tasks in reverberating and noisy environments. Since supervised machine learning approaches require large-sized, physically realistic, precisely labelled datasets, a fast graphics processing unit-based computation of room impulse responses was developed using fractional delays for image source models. A thorough analysis of the network representation and extensive performance tests are carried out using the BeamLearning network with synthetic and experimental datasets. Obtained results demonstrate that the BeamLearning approach significantly outperforms the wideband MUSIC and steered response power-phase transform methods in terms of localization accuracy and computational efficiency in the presence of heavy measurement noise and reverberation.

Scrotal thermoregulation and sequential sperm abnormalities in buffalo bulls (Bubalus bubalis) under short-term heat stress.

Heat stress reduces the reproductive capacity of bulls raised in tropical climate. However, the reestablishment of scrotal thermoregulation and the dynamics of sperm defects emergence after stress are not completely known in buffaloes. Thus, the study aimed to evaluate the effect of short-term heat stress over scrotal thermoregulation and sperm attributes, relating them to spermatogenesis stages. Five buffalo bulls went through scrotal insulation during 48 h (from day 0 to day 2). Semen samples were collected every 7 days (from day -7 to day 49) and analyzed about the progressive motility, viability, and sperm morphology. Heat stress significantly destabilized scrotal thermoregulation (P < 0.001). Scrotal temperature was from 4.2 to 6.3 °C lower than the core body temperature, except on insulation days (P < 0.001), and returned to the basal condition five days after the removal of the stressing stimulus. More significant deleterious effects were observed in sperm morphology than in cell concentration, motility, and viability. The chronology of morphologic defects expression demonstrated tail defects (days 7-14), cytoplasmic droplets (days 14-28), and head defects (day 28), returning to pre-insulation condition 35 days after the thermal challenge. Thus, hyperthermia harmed more intensely spermatozoa in epididymal transit, elongated spermatids, and secondary spermatocytes. It is concluded that water buffalo bulls present a peculiar manifestation of sperm morphology after short-term stress, indicating an important difference related to the bovine species. Therefore, during the andrological evaluation of buffalo bulls, it is necessary to avoid the allometric extrapolation between these species.

Water buffalo production in the Brazilian Amazon Basin: a review.

The Brazilian Amazon has witnessed, in the last decades, an increase in the water buffalo (Bubalus bubalis) inventory, with interesting productivity results. As the Brazilian Amazon contains the main water buffalo population in the Americas, the aim of this work is to review its most relevant production systems and some peculiarities about meat and milk production in this territory. The opening section describes the Amazon Basin, the most common water buffalo breeds, a brief history of the local livestock farming beginning in 1644. Also, it presents how water buffaloes gradually replaced bovine herds, especially where the latter had a lower productive performance. The use of extensive or more intensified models is pointed out and the ecosystems in which buffaloes are raised are detailed since native or cultivated pastures can be used in floodplains or drylands. Buffalo raising is favored in the Amazon due to the climate, soil, genetic variability of forages, animal adaptability, and physical space. Thus, it is clear that buffaloes have a high potential for meat and milk production and are an alternative in the use of altered areas of the Amazon; and, in the recent past, the low profitability of buffalo farming in traditional production systems in the Amazon was the reason which made this activity economically unattractive. Most recent technologies as outdoor confinements and silvopastoral systems are pointed out as more suitable regarding land-use policies, and buffalo farming for meat and milk production fits perfectly in this context, with productivity and beneficial socioeconomic.

Innovative use and efficiency test of subcutaneous transponders for electronic identification of water buffaloes.

The objective of this study was to evaluate the viability of using transponders for the electronic identification of water buffaloes and compare their efficiency when used in animals of different age groups. Electronic transponders with RFID technology (2.1 × 12.2 mm) were implanted subcutaneously (D0) in the scutiform cartilage. The animals consisted of four groups: CLF-I (17 calves; 2.1 ± 1.9 months), CLF-II (20 calves; 5.1 ± 3.2 months), HFR (20 heifers; 22 ± 4.7 months) and STR (19 steers; 26.6 ± 6.7 months). The animals were kept under pasture grazing, a part of the year in the dryland and a part in the floodplain, and were monitored for up to 350 days. The average time required for individual transponder implant was 49.46 s, while the time required for reading the code was 3.76 s. The older calves required higher time for individual implant (P = 0.0001) and closer approximation of the reader in the D150 (P = 0.0001). The mean read distance was 2.98 cm in D0 and 1.94 cm in D150. The magnitude of the subcutaneous transponder migration was minimal, and was within an area of 17.2 mm2. A slight bleeding was observed in 15.79% of the animals during the implant. A decreasing incidence of edema was observed until D21, with the heifers being more sensitive until that time (P = 0.0099). Considering the results, it is preferred to implant electronic transponders in calves up to two months of age. The physical rate of transponder loss was 1.3% and the loss of functionality was 9.2%. High reading rate was achieved when animals were raised both in dryland (93.9%) and floodplain (97.2%). Thus, the electronic identification of water buffaloes is a technique capable of replacing traditional and rudimentary methods to identify buffaloes and can provide safe identification of animals.

Influence of post-thawing thermal environment on bovine sperm characteristics and in vitro fertility.

Our aim was to evaluate the effects of three thermal environments over time on kinetics, functionality and in vitro fertility of cryopreserved bovine spermatozoa. Four ejaculates from five bulls (n = 20) were cryopreserved. After thawing, semen was evaluated (0 hr), incubated for 4 hr in T36.0 (36.0°C), T38.0 (38.0°C) and T39.5 (39.5°C), and analysed every hour (1 hr, 2 hr, 3 hr, 4 hr). In vitro production of embryos was performed at 0 hr and 4 hr. Sperm motility and cell kinetics (Computer-Assisted Sperm Analysis) were impaired after 2 hr at T38.0 and T39.5 (p < 0.05). Flow cytometry revealed an increase in the cells with injured plasma membrane to 39.5°C and a general reduction in the mitochondrial potential over time (p < 0.05). In vitro fertility was impaired in all temperatures after 4 hr, but there was no difference between 36.0°C and 38.0°C. Our results suggest that the ex situ resilience of semen at 36.0°C after thawing with no major damage to the quality is limited to 3 hr. In normothermia or in thermal stress, sperm cells present a gradual reduction of movement and functionality, which were more significant after 1 hr of incubation. The in vitro production of embryos is impaired when the semen is kept in a thermal environment ≥36.0°C for 4 hr.

Comparison of the intravenous and intravaginal route of oxytocin administration for cervical dilation protocol and non-surgical embryo recovery in oestrous-induced Santa Inês ewes.

This study compared the effects of intravaginal and intravenous routes of oxytocin (OT) administration in 46 oestrous-induced Santa Inês ewes (6-day treatment with progestin-releasing intravaginal sponges and a single injection of 200 IU of eCG at the time of sponge removal) that underwent transcervical embryo recovery 6-7 days after oestrous onset and mating. All ewes received 37.5 µg of d-cloprostenol via latero-vulvar route, and 1 mg of oestradiol benzoate i.m. 16 hr before and 50 IU of OT 20 min before non-surgical embryo recovery (NSER), with OT being administered intravenously (n = 21) or intravaginally (n = 21). An overall oestrous response was 95.6% (44/46), and adequate cervical retraction could be accomplished in 78.6% (33/42) of ewes. The percentage of successful NSER procedures was 57% (24/42) or 72.7% (24/33) of animals with sufficient cervical retraction. The duration of NSER procedure averaged 28 min (range: 17-40 min) and ~96% of flushing fluid could be recovered (range: 85%-100%). Out of 18 ewes that could not undergo NSER, 12 (66.6%) presented various anatomical barriers, whilst the other 33.4% did not present these barriers and still could not be traversed. Excluding the ewes with those anatomical features, the overall success rate of NSER was 80% (24/30). The route of OT administration had no effect on NSER efficiency or the ease with which transcervical embryo flushing was performed. Both routes of OT administration can be used for cervical dilation protocol. Discarding ewes with anatomical features precluding cervical penetration is highly recommended to increase the efficacy of NSER in sheep.

Animal thermal comfort indexes in silvopastoral systems with different tree arrangements.

This study aimed to assess solar radiation transmission and animal thermal comfort indexes in two silvopastoral systems established with different tree arrangements in a tropical region. This study was conducted between 2014 and 2017 in two silvopastoral systems, one composed by an established Urochloa (syn. Brachiaria) decumbens pasture with Brazilian native trees planted in triple rows spaced 17 m apart, and another by an established Urochloa (syn. Brachiaria) brizantha (Hochst ex A. Rich.) Stapf 'BRS Piatã' pasture with Eucalyptus urograndis (clone GG100) trees arranged in single rows spaced 15 m apart. In these systems and in a full-sun pasture, photosynthetically active radiation transmission, air temperature, relative humidity, black globe temperature, and wind speed were measured. These variables were used to calculate black globe temperature and humidity index (BGHI) and radiant thermal load (RTL). Higher animal thermal comfort was observed in the silvopastoral systems due to changes in the microclimate induced by the trees; notably, a decrease in solar radiation transmission. Fewer hours of potential animal thermal stress (BGHI>79) were observed in the silvopastoral systems than under the full-sun conditions, with differences up to 3 h per day. The silvopastoral systems presented lower radiant thermal load than the full-sun pasture with differences up to 22% achieved. The assessed silvopastoral systems may help livestock adapt to climate change, since they achieved the limit of BGHI considered to cause stress to animals following an increase of 2.2 °C in air temperature, compared with full-sun pastures.

Application of microchip and infrared thermography for monitoring body temperature of beef cattle kept on pasture.

The monitoring of body temperature is important for the diagnosis of the physiological state of the animal, being dependent on available methods and their applicability within production systems. This work evaluated techniques to monitor the body temperature of beef cattle kept on pasture and their ability to predict internal temperature. Twenty-three adult bovine females were monitored for six months, and collection data carried out in eleven campaigns (D0-D10) twelve days apart. During collections, the surface temperatures of ear base (ET, oC) and ocular globe (OGT, oC) were measured by infrared thermography, and the subcutaneous temperature (ST, oC) was measured with the use of transponder containing an implantable microchip. Rectal temperature (RT, oC) was considered as a reference for body temperature. Temperature and Humidity Index (THI), Black Globe Temperature and Humidity Index (BGHI) and Radiant Heat Load (RHL, W/m2) were calculated. ET (33.32 ±â€¯0.12 °C), ST (36.10 ±â€¯0.07 °C), OGT (37.40 ±â€¯0.06 °C) and RT (38.83 ±â€¯0.03 °C) differed significantly (P˂0.05). There was positive correlation of RT with OGT (r = 0.392), ET (r = 0.264) and ST (r = 0.236) (P˂0.05). Considering the bioclimatic indicators, the highest magnitude correlations were observed between ET and THI (r = 0.71), ET and BGHI (r = 0.65), and ET and RHL (r = 0.48). The use of microchip represented a practical method, but with limited predictability. On the other hand, infrared thermography proved to be safe and non-invasive, presenting greater precision for inference of internal body temperature. ET was more influenced by meteorological conditions.

Productive performance and reproductive characteristics of Morada Nova male lambs fed with high-energy diet.

Morada Nova breed sheep are without wool, tropicalized, small-sized animals, known for their high-quality meat and skin. Their body development naturally depends on the genetic potential and adequate nutritional support, which suggests that the offer of high-energy density diets positively influences their productive indicators. Thus, the present study investigated the effect of a high-energy diet for the Morada Nova lambs on body development and testicular function, considering their histomorphometric characteristics and seminal quality. Forty-two males (19.2 weeks, 20.7 ± 3.5 kg) were equally divided into two groups and fed with 2.05 Mcal (G7, n = 21) or 2.37 Mcal (G24, n = 21) of metabolizable energy/day, equivalent to 7% and 24% above the minimum for growing lambs. The animals were confined for 23 weeks (W0 to W23). Weight and body score differed significantly from the W1 (P < 0.05). From the W5, thoracic perimeter, body length, wither height, and rump attributes were higher in G24 (P < 0.05). The scrotal circumference and testicular volume were higher in G24 from the W3 (P < 0.05). Although testosterone levels were not affected (P = 0.05), the highest energy intake increased the diameter of the seminiferous tubules and the development of the epididymal epithelium (P < 0.05). This positively influenced the seminal quality and reduced the minor defects (21.87% vs. 17.13%) and the total spermatic defects (26.34% vs. 21.78%, P < 0.05). Thus, it is possible to employ higher levels of dietary energy for Morada Nova young males to express higher productive efficiency and earlier reproductive attributes of interest.

Mapping of novel salt tolerance QTL in an Excalibur × Kukri doubled haploid wheat population.

KEY MESSAGE: Novel QTL for salinity tolerance traits have been detected using non-destructive and destructive phenotyping in bread wheat and were shown to be linked to improvements in yield in saline fields. Soil salinity is a major limitation to cereal production. Breeding new salt-tolerant cultivars has the potential to improve cereal crop yields. In this study, a doubled haploid bread wheat mapping population, derived from the bi-parental cross of Excalibur × Kukri, was grown in a glasshouse under control and salinity treatments and evaluated using high-throughput non-destructive imaging technology. Quantitative trait locus (QTL) analysis of this population detected multiple QTL under salt and control treatments. Of these, six QTL were detected in the salt treatment including one for maintenance of shoot growth under salinity (QG(1-5).asl-7A), one for leaf Na+ exclusion (QNa.asl-7A) and four for leaf K+ accumulation (QK.asl-2B.1, QK.asl-2B.2, QK.asl-5A and QK:Na.asl-6A). The beneficial allele for QG(1-5).asl-7A (the maintenance of shoot growth under salinity) was present in six out of 44 mainly Australian bread and durum wheat cultivars. The effect of each QTL allele on grain yield was tested in a range of salinity concentrations at three field sites across 2 years. In six out of nine field trials with different levels of salinity stress, lines with alleles for Na+ exclusion and/or K+ maintenance at three QTL (QNa.asl-7A, QK.asl-2B.2 and QK:Na.asl-6A) excluded more Na+ or accumulated more K+ compared to lines without these alleles. Importantly, the QK.asl-2B.2 allele for higher K+ accumulation was found to be associated with higher grain yield at all field sites. Several alleles at other QTL were associated with higher grain yields at selected field sites.

Non-surgical embryo transfer in goats and sheep: the Brazilian experience.

Brazil has presented tremendous progress in non-surgical embryo transfer (NSET) in sheep and goats. New instruments and techniques for non-surgical embryo recovery (NSER) and NSET in small ruminants were implemented. Recent improvements include refinement of the protocols for cervical relaxation combining oestradiol-oxytocin-cloprostenol treatment at specific times before NSER in sheep; recipient goats do not require any hormonal drugs to induce cervical dilation and direct embryo transfer by the cervical route yields excellent results. Transrectal ovarian ultrasonography (B-mode but especially colour Doppler) have proven to be accurate methods to localise and enumerate corpora lutea and luteinised unovulated follicles in recipient and donor does and ewes. An array of new criteria for selecting superior animals for NSER and NSET (e.g. cervical mapping) have been developed by Brazilian researchers. Extensive studies on both technologies were initially conducted in commercial breeds of goats and sheep but have been gradually extended to some native breeds of sheep (germplasm conservation) and dairy goat operations. It is speculated that, in future, NSER and NSET may become methods of choice for caprine and ovine embryo recovery and transfer in Brazil, and then globally. Due primarily to the efficiency of NSET in goats, a novel interspecies (e.g. bovine) IVP method may soon be developed on a large scale. The Brazilian experience is an invaluable source of information and know-how promoting the replacement of conventional surgical assisted reproductive technologies with non-surgical procedures and hence supporting the rapid development of the embryo transfer industry in small ruminants.

Thermoregulatory responses and reproductive traits in composite beef bulls raised in a tropical climate.

It is believed that increased livestock production is limited by tropical climate. Thermal imbalance in bulls can lead to hyperthermia and alter testicular metabolism, causing subfertility or infertility. Therefore, the thermoregulation of composite Canchim bulls (5/8 Charolais × 3/8 Zebu) raised in tropical climate as well as their consequences in the physiological, hematological, hormonal, and andrological parameters were evaluated monthly. The bulls (n = 18; 30.0 ± 1.5 months; 503.8 ± 23.0 kg) were kept on pasture, in a single group, from August 2015 to March 2016, comprising the winter, spring, and summer seasons. Biometeorological variables were continuously monitored, and the Temperature and Humidity Index (THI) was calculated. A greater thermal challenge occurred in spring and summer (THI ≥ 72.0). Nevertheless, the bulls exhibited normothermia (38.6 to 38.9 °C) in these seasons. The cortisol did not vary between seasons (7.0 vs. 8.7 vs. 6.8 ng/mL; P > 0.05) and remained within the physiological patterns. Independent of the seasons, stress leukogram was also not observed, refuting the incidence of acute or chronic thermal stress. It is noteworthy that T3 and testosterone increased (P < 0.0001, P < 0.05) in spring and summer, the time that coincides with the breeding season, when there is increased metabolic requirement from the bulls. The progressive thermal challenge increase did not affect the scrotal thermoregulatory capacity, and in general, scrotal temperature remained at 5.2 °C below the internal body temperature. In summer, there was a 5% reduction in the minor sperm defects (P < 0.05) and DNA fragmentation in 2.4% of spermatozoa, a compatible value for high fertility bulls. The results show that the studied composite bulls can be considered as climatically adapted and constitute a viable alternative to be used in production systems in a tropical climate, even if the breeding seasons occur during the most critical thermal condition periods of the year.

Cancellation of room reflections over an extended area using Ambisonics.

This paper investigates the compensation of room reflections based on Ambisonics. A multichannel room equalization method for Ambisonic playback systems is proposed. The compensation filters are designed to operate in the spherical harmonics domain, prior to the decoding step. Their design requires the inversion of a matrix which can be ill-conditioned at low frequencies and for higher Ambisonic orders. A crossover and cross-order method is proposed to circumvent this problem and to reduce the amount of necessary regularization. Simulation results are presented in frequency, space, and temporal domains over a wide-range of frequencies. It is shown that the proposed method is efficient and can reduce the reproduction error to -14 dB in the reconstruction area defined in free field. Practical considerations such as Ambisonic room response estimation and robustness of the method are investigated. Experimental results are provided and show good agreement with the theory. Finally, a glimpse into the extension of the proposed method to create three-dimensional measurement-based Ambisonic reverberation is discussed.