Bamboo forage in Peruvian Amazon: a potential feed for cattle.

During the dry and rainy seasons of the Northeastern Zone of Peru, a chemical characterization of five species of bamboo prevalent in the area (Guadua lynnclarkiae, G. takahashiae, Bambusa vulgaris, G. weberbaueri, and Dendrocalamus asper) was conducted. Then, the effect of supplementing bamboo leaves (0, 20, and 40% inclusion of D. asper) on the intake and live weight gain of 18 Gyr × Holstein heifers was evaluated for 28 days. Among the species evaluated, D. asper has the greatest crude protein (CP) concentration (158-166 g/kg Dry matter- DM), post-ruminal CP supply (127 g/kg DM), and in vitro organic matter digestibility (444-456 g/kg DM) but similar concentrations of crude ash (124 g/kg DM), calcium (2.4-2.8 mg/g), phosphorus (0.7-2.1 mg/g), protein fractions A, B1, B2, B3, C (45, 5, 35, 56, and 17g/kg DM, respectively), rumen-undegraded CP (31% CP), neutral detergent fiber (NDF, 685g/kg DM), and acid detergent fiber (ADF, 357 g/kg DM) than the other species evaluated. Dry matter intake was higher in the control treatment and in the 20% bamboo leaf inclusion treatment than in the 40% bamboo inclusion treatment. Intake of CP and NDF decreased with the increase in bamboo inclusion. Despite the differences in DM, CP, and NDF intake, the live weight gain remained similar across treatments. However, there was a greater feed conversion in the 20% bamboo leaf inclusion treatment. During the dry season, bamboo leaves can be used as an alternative supplement at a maximum inclusion of 20% without affecting the live weight gain.

Driver Take-Over Behaviour Study Based on Gaze Focalization and Vehicle Data in CARLA Simulator.

Autonomous vehicles are the near future of the automobile industry. However, until they reach Level 5, humans and cars will share this intermediate future. Therefore, studying the transition between autonomous and manual modes is a fascinating topic. Automated vehicles may still need to occasionally hand the control to drivers due to technology limitations and legal requirements. This paper presents a study of driver behaviour in the transition between autonomous and manual modes using a CARLA simulator. To our knowledge, this is the first take-over study with transitions conducted on this simulator. For this purpose, we obtain driver gaze focalization and fuse it with the road's semantic segmentation to track to where and when the user is paying attention, besides the actuators' reaction-time measurements provided in the literature. To track gaze focalization in a non-intrusive and inexpensive way, we use a method based on a camera developed in previous works. We devised it with the OpenFace 2.0 toolkit and a NARMAX calibration method. It transforms the face parameters extracted by the toolkit into the point where the user is looking on the simulator scene. The study was carried out by different users using our simulator, which is composed of three screens, a steering wheel and pedals. We distributed this proposal in two different computer systems due to the computational cost of the simulator based on the CARLA simulator. The robot operating system (ROS) framework is in charge of the communication of both systems to provide portability and flexibility to the proposal. Results of the transition analysis are provided using state-of-the-art metrics and a novel driver situation-awareness metric for 20 users in two different scenarios.

Diverged subpopulations in tropical Urochloa (Brachiaria) forage species indicate a role for facultative apomixis and varying ploidy in their population structure and evolution.

BACKGROUND: Urochloa (syn. Brachiaria) is a genus of tropical grasses sown as forage feedstock, particularly in marginal soils. Here we aimed to clarify the genetic diversity and population structure in Urochloa species to understand better how population evolution relates to ploidy level and occurrence of apomictic reproduction. METHODS: We explored the genetic diversity of 111 accessions from the five Urochloa species used to develop commercial cultivars. These accessions were conserved from wild materials collected at their centre of origin in Africa, and they tentatively represent the complete Urochloa gene pool used in breeding programmes. We used RNA-sequencing to generate 1.1 million single nucleotide polymorphism loci. We employed genetic admixture, principal component and phylogenetic analyses to define subpopulations. RESULTS: We observed three highly differentiated subpopulations in U. brizantha, which were unrelated to ploidy: one intermixed with U. decumbens, and two diverged from the former and the other species in the complex. We also observed two subpopulations in U. humidicola, unrelated to ploidy; one subpopulation had fewer accessions but included the only characterized sexual accession in the species. Our results also supported a division of U. decumbens between diploids and polyploids, and no subpopulations within U. ruziziensis and U. maxima. CONCLUSIONS: Polyploid U. decumbens are more closely related to polyploid U. brizantha than to diploid U. decumbens, which supports the divergence of both polyploid groups from a common tetraploid ancestor and provides evidence for the hybridization barrier of ploidy. The three differentiated subpopulations of apomictic polyploid U. brizantha accessions constitute diverged ecotypes, which can probably be utilized in hybrid breeding. Subpopulations were not observed in non-apomictic U. ruziziensis. Sexual Urochloa polyploids were not found (U. brizantha, U. decumbens) or were limited to small subpopulations (U. humidicola). The subpopulation structure observed in the Urochloa sexual-apomictic multiploidy complexes supports geographical parthenogenesis, where the polyploid genotypes exploit the evolutionary advantage of apomixis, i.e. uniparental reproduction and clonality, to occupy extensive geographical areas.

Gaze Focalization System for Driving Applications Using OpenFace 2.0 Toolkit with NARMAX Algorithm in Accidental Scenarios.

Monitoring driver attention using the gaze estimation is a typical approach used on road scenes. This indicator is of great importance for safe driving, specially on Level 3 and Level 4 automation systems, where the take over request control strategy could be based on the driver's gaze estimation. Nowadays, gaze estimation techniques used in the state-of-the-art are intrusive and costly, and these two aspects are limiting the usage of these techniques on real vehicles. To test this kind of application, there are some databases focused on critical situations in simulation, but they do not show real accidents because of the complexity and the danger to record them. Within this context, this paper presents a low-cost and non-intrusive camera-based gaze mapping system integrating the open-source state-of-the-art OpenFace 2.0 Toolkit to visualize the driver focalization on a database composed of recorded real traffic scenes through a heat map using NARMAX (Nonlinear AutoRegressive Moving Average model with eXogenous inputs) to establish the correspondence between the OpenFace 2.0 parameters and the screen region the user is looking at. This proposal is an improvement of our previous work, which was based on a linear approximation using a projection matrix. The proposal has been validated using the recent and challenging public database DADA2000, which has 2000 video sequences with annotated driving scenarios based on real accidents. We compare our proposal with our previous one and with an expensive desktop-mounted eye-tracker, obtaining on par results. We proved that this method can be used to record driver attention databases.

Drive-By-Wire Development Process Based on ROS for an Autonomous Electric Vehicle.

This paper presents the development process of a robust and ROS-based Drive-By-Wire system designed for an autonomous electric vehicle from scratch over an open source chassis. A revision of the vehicle characteristics and the different modules of our navigation architecture is carried out to put in context our Drive-by-Wire system. The system is composed of a Steer-By-Wire module and a Throttle-By-Wire module that allow driving the vehicle by using some commands of lineal speed and curvature, which are sent through a local network from the control unit of the vehicle. Additionally, a Manual/Automatic switching system has been implemented, which allows the driver to activate the autonomous driving and safely taking control of the vehicle at any time. Finally, some validation tests were performed for our Drive-By-Wire system, as a part of our whole autonomous navigation architecture, showing the good working of our proposal. The results prove that the Drive-By-Wire system has the behaviour and necessary requirements to automate an electric vehicle. In addition, after 812 h of testing, it was proven that it is a robust Drive-By-Wire system, with high reliability. The developed system is the basis for the validation and implementation of new autonomous navigation techniques developed within the group in a real vehicle.

Review: Strategies for enteric methane mitigation in cattle fed tropical forages.

Methane (CH4) is a greenhouse gas (GHG) produced and released by eructation to the atmosphere in large volumes by ruminants. Enteric CH4 contributes significantly to global GHG emissions arising from animal agriculture. It has been contended that tropical grasses produce higher emissions of enteric CH4 than temperate grasses, when they are fed to ruminants. A number of experiments have been performed in respiration chambers and head-boxes to assess the enteric CH4 mitigation potential of foliage and pods of tropical plants, as well as nitrates (NO3-) and vegetable oils in practical rations for cattle. On the basis of individual determinations of enteric CH4 carried out in respiration chambers, the average CH4 yield for cattle fed low-quality tropical grasses (>70% ration DM) was 17.0 g CH4/kg DM intake. Results showed that when foliage and ground pods of tropical trees and shrubs were incorporated in cattle rations, methane yield (g CH4/kg DM intake) was decreased by 10% to 25%, depending on plant species and level of intake of the ration. Incorporation of nitrates and vegetable oils in the ration decreased enteric CH4 yield by ∼6% to ∼20%, respectively. Condensed tannins, saponins and starch contained in foliages, pods and seeds of tropical trees and shrubs, as well as nitrates and vegetable oils, can be fed to cattle to mitigate enteric CH4 emissions under smallholder conditions. Strategies for enteric CH4 mitigation in cattle grazing low-quality tropical forages can effectively increase productivity while decreasing enteric CH4 emissions in absolute terms and per unit of product (e.g. meat, milk), thus reducing the contribution of ruminants to GHG emissions and therefore to climate change.

Accuracy of genomic prediction of shell quality in a White Leghorn line.

Several genomic methods were applied for predicting shell quality traits recorded at 4 different hen ages in a White Leghorn line. The accuracies of genomic prediction of single-step GBLUP and single-trait Bayes B were compared with predictions of breeding values based on pedigree-BLUP under single-trait or multitrait models. Breaking strength (BS) and dynamic stiffness (Kdyn) measurements were collected on 18,524 birds from 3 consecutive generations, of which 4,164 animals also had genotypes from an Affymetrix 50K panel containing 49,591 SNPs after quality control edits. All traits had low to moderate heritability, ranging from 0.17 for BS to 0.34 for Kdyn. The highest accuracies of prediction were obtained for the multitrait single-step model. The use of marker information resulted in higher prediction accuracies than pedigree-based models for almost all traits. A genome-wide association study based on a Bayes B model was conducted to detect regions explaining the largest proportion of genetic variance. Across all 8 shell quality traits analyzed, 7 regions each explaining over 2% of genetic variance and 54 regions each explaining over 1% of genetic variance were identified. The windows explaining a large proportion of genetic variance overlapped with several potential candidate genes with biological functions linked to shell formation. A multitrait repeatability model using a single-step method is recommended for genomic evaluation of shell quality in layer chickens.

Speed of in vitro embryo development affects the likelihood of foaling and the foal sex ratio.

The success of invitro embryo production (IVEP) in horses has increased considerably during recent years, but little is known about the effect of the speed of invitro embryo development. Blastocysts (n=390) were produced by intracytoplasmic sperm injection of IVM oocytes from warmblood mares, cryopreserved, thawed and transferred into recipient mares on Days 3, 4, 5 or 6 after ovulation. The time required for invitro-produced (IVP) embryos to reach the blastocyst stage was recorded (Day 7 vs Day 8). The likelihood of foaling was affected by the speed of invitro embryo development and recipient day after ovulation at transfer. The odds ratio for foaling was ~0.63 for transfer of Day 8 (46%) compared with Day 7 (56%) IVP blastocysts. The highest likelihood of pregnancy (72%) and foaling (60%) was observed when IVP blastocysts were transferred to recipient mares on Day 4 after ovulation. Finally, the sex (colt:filly) ratio was higher after transfer of Day 7 (71%:29%) than Day 8 (54%:46%) IVP blastocysts, suggesting that the speed of embryo development is sex dependent. In conclusion, the speed of invitro embryo development in our IVEP system affects the likelihood of foaling and the sex of the foal.

Monozygotic multiple pregnancies after transfer of single in vitro produced equine embryos.

BACKGROUND: Monozygotic multiple pregnancy is rare in horses, but may be more common after transfer of an in vitro produced (IVP) embryo. OBJECTIVES: To determine the occurrence, incidence, characteristics and outcome of monozygotic siblings arising from in vivo and IVP equine embryos. STUDY DESIGN: Retrospective case series. METHODS: A total of 496 fresh in vivo and 410 frozen-thawed IVP blastocysts, produced by intracytoplasmic sperm injection (ICSI) of in vitro matured oocytes from Warmblood mares, were transferred into recipient mares. The likelihoods of pregnancy and multiple pregnancy were calculated, and the clinical features and outcome of any multiple pregnancy were recorded. RESULTS: The likelihood of pregnancy after transfer of a single IVP or in vivo embryo was 62% (254/410) and 83% (413/496) respectively. The incidence of multiple pregnancy was 1.6% (4/254) and 0% (0/413) for IVP and in vivo blastocysts, respectively. More specifically, three IVP blastocysts yielded twin embryo propers/fetuses, and one IVP conceptus developed three distinct embryonic bodies. Interestingly, only one embryonic vesicle was detected at all ultrasonographic examinations prior to embryo proper development. Multiple embryonic bodies only became apparent at later scans to check for an embryo proper and heartbeat, or when the recipient mare aborted. Two twin pregnancies aborted spontaneously at 3 and 9 months, respectively, while the heartbeat was lost from all three embryos in the triplet pregnancy before day 35 of gestation. Twin reduction by per rectum compression of one fetal thorax was attempted at day 50 of gestation in the fourth case; however, both fetuses were lost. MAIN LIMITATIONS: Small number of cases. CONCLUSIONS: In vitro embryo production resulted in a higher incidence of multiple monozygotic pregnancy, which could only be diagnosed after development of the embryo proper and is likely to result in pregnancy loss later in gestation if left untreated.

Effects of follicular ablation and induced luteolysis on LH and follicular fluid factors during the periovulatory period in mares.

Haemorrhagic anovulatory follicles (HAFs) are the most common pathological anovulatory condition in the mare. To enhance understanding of the physiopathology of HAFs, the aim of the present study was to determine the effects of an induced-follicular wave on LH concentrations and follicular fluid factors relevant to the ovulatory process. Mares were allocated to treatment or control groups (n = 7/group) in a crossed over design during 14 oestrous cycles with a period of one cycle occurring when there were no treatments between the times when treatments were administered. In the treatment group, all antral follicles ≥8 mm were ablated on Day 10 after ovulation followed by administration of a luteolytic dose of PGF2α. All mares of both groups were treated with 1500 IU of hCG when a follicle ≥32 mm was detected (Hour 0), and follicular fluid was aspirated 35 h later. Blood samples were collected every 48 h from Day 10 until Hour 0 from all mares. Follicular fluid was assayed for PGE2, estradiol and progesterone. Plasma was assayed for LH concentrations. A follicular wave followed follicle ablation in the treated mares. Concentrations of LH were greater (P = 0.05) in mares ot the treatment compared with control group. Concentrations of PGE2, estradiol and progesterone in follicular fluid did not differ between groups (P > 0.05). Treatment resulted in an earlier increase in circulating LH, however, there was no effect on concentrations of intra-follicular PGE2, estradiol or progesterone in hCG-stimulated preovulatory follicles.

Smart forage selection could significantly improve soil health in the tropics.

The use of tropical grasslands to graze livestock is of high economic importance. Declining grassland soil health leads to reduced sustainability of livestock systems. There are high levels of phenotypic diversity amongst tropical forage grasses. We hypothesise that this variation could lead to significant differences in soil health and that selection of forage cultivars to improve soil health could improve the sustainability of livestock production. We measured and compared key soil health metrics (soil organic carbon (SOC) concentration and sugar / alkane composition, aggregate stability, friability, litter decomposition rates, microbial community composition) under four tropical forage varieties (Brachiaria hybrid cv Mulato (BhMulato), B. humidicola cv Tully (CIAT679; Bh679), B. humidicola cv CIAT16888 (Bh16888), and Panicum maximum CIAT 6962 (Pmax)) and a bare soil control, there was a significant difference in soil aggregate stability, friability and SOC concentration between the forage varieties with soil under Bh679 and Bh16888 tending to have greater aggregate stability, friability and SOC concentrations compared to the soil under BhMulato and Pmax. We identified significant spatial variation in soils under BhMulato and Pmax due to their tussock forming growth habit; when compared to soil from adjacent to the tussocks, soil from the gaps between tussocks had significantly reduced aggregate stability under both species, significantly reduced friability under Pmax and significantly reduced SOC under BhMulato. We found limited impact of forage variety on soil microbial community composition, litter decomposition rates or soil alkane and sugar concentrations.

Investigating the genetic determination of clutch traits in laying hens.

Clutch traits were proposed as a more detailed description of egg-laying patterns than simple total egg production. In this study, egg production of 23,809 Rhode Island Red (RIR) and 22,210 White Leghorn (WL) hens was described in terms of number of clutches, average and maximum clutch size, age at first egg, total saleable egg production, and percentage of egg defects. Genetic parameters were estimated using a six-trait animal model. Of the phenotyped birds, 1433 RIR hens and 1515 WL hens were genotyped with line specific 50K Affymetrix Axiom single nucleotide polymorphism chips to perform genome-wide association analyses. Moderate heritabilities were estimated for clutch traits of 0.20 to 0.42 in the RIR line and 0.29 to 0.41 in the WL line. Average and maximum clutch size was positively genetically correlated with total saleable egg number in both lines. Genome-wide association analysis identified seven regions that were associated with egg production in the RIR line and 12 regions in the WL line. The regions identified were line and trait specific, except for one region on chromosome 6 from 28 to 29 Mb that influenced number of clutches and maximum and average clutch size in WL hens. Regions associated with egg production identified here overlapped with 260 genes, with some strong positional candidates based on gene ontology including WASH1, which is involved in oocyte maturation, NPVF, involved in regulation of follicle-stimulating hormone secretion, and FOXO3, involved in oocyte maturation and ovulation from the ovarian follicle. Confirmation of the role of these genes in regulation of egg production pattern will require further studies.

Factors affecting the likelihood of pregnancy and embryonic loss after transfer of cryopreserved in vitro produced equine embryos.

BACKGROUND: In vitro embryo production (IVEP) is increasingly popular but data assessing the outcome of transferred embryos are scarce. OBJECTIVES: To determine the likelihood of pregnancy and embryonic loss after transfer of frozen-thawed IVP embryos and identify factors influencing success. STUDY DESIGN: Retrospective clinical study. METHODS: Blastocysts (n = 261) were produced from immature oocytes of Warmblood mares (n = 116) by Intracytoplasmic Sperm Injection (ICSI) and in vitro culture, and cryopreserved. Thawed IVP embryos were transferred into recipient mares on day 4, 5 or 6 after ovulation. The influence of donor mare (age, reproductive history), recipient mare (age, reproductive status, management; in-house vs. outpatient, day post-ovulation), embryo (interval from ICSI to blastocyst formation) and management factors (season when ovum pickup was performed, year and method of transfer) on likelihood of pregnancy and embryonic loss was examined, and the developmental stage of the IVP embryo at the time of transfer was estimated. RESULTS: The percentage of mares pregnant 7-10, 23 and 37 days after transfer was 56% (147/261), 49% (129/261), and 48% (124/261), respectively. Development of IVP embryos after transfer equated to day 5 or 6 in vivo embryos. With the exception of year of transfer, none of the factors had an impact on the likelihood of pregnancy or embryonic loss. Nevertheless, the likelihood of pregnancy tended to be lower for IVP embryos from infertile mares or when embryos were transferred into recipient mares on day 6 after ovulation rather than on day 4 or 5. Finally, the diameter of the embryonic vesicle 7 days post transfer was lower for pregnancies that were lost compared to those that were maintained. MAIN LIMITATIONS: Small sample size in some of the donor and recipient mare categories. CONCLUSIONS: Cryopreserved IVP embryos should be transferred into recipient mares on day 4 or 5 after ovulation and a slower rate of post transfer vesicle expansion indicates a higher risk of subsequent embryonic loss The Summary is available in Portuguese - see Supporting Information.

Genome wide association study for heat stress induced mortality in a white egg layer line.

High environmental temperature is a serious stress affecting economic and biological efficiency of poultry production in tropical and subtropical countries that is expected to become more prominent with global climate change. Iowa experienced 3 acute heat waves of 11, 3, and 4 d of heat index above 38°C in the summer of 2012, which led to production losses and increased bird mortality. For the current study, the proportion of daughters that died from heat stress during this period was calculated for 118 sire families of an elite White Leghorn layer line. The number of daughters per sire ranged from 25 to 111 and averaged 68. Average mortality due to heat stress was 8.2%, ranging from 0 to 24.6%. All sires were genotyped using a 600 K Affymetrix chip. After stringent quality filtering (clustering quality, parentage, missing genotypes, MAF) 113,344 SNPs were retained for the analysis. Method BayesB with π equal to 0.999, for the number of markers fitted not to exceed the number of observations, was applied. Markers explained 8% of the phenotypic variance. One 1-Mb window on chromosome 5 explained 1.2% of genetic variance. When the number of daughters was fitted as a weight in the analysis, the proportion of variance explained by markers dropped to 1%, but 9 1-Mb windows explained more than 1% of genetic variance on chromosomes 1, 3, 5 (the same top window as in the unweighted analysis), 9, 17, and 18. Although the support of the genomic regions associated with heat stress resistance identified in this study was not very strong, they overlapped with previously reported quantitative trait loci regions for immune response and physiological traits in chickens and contained genes that have been associated with response to heat stress in other studies. Further research is needed to validate the results.

Small day 8 equine embryos cannot be rescued by a less advanced recipient mare uterus.

Equine embryos tolerate an unusually large degree of negative uterine asynchrony (recipient mare up to 5 days behind the donor mare). By contrast, positive asynchrony of more than 2 days results in a high incidence of early embryonic loss (EEL). Day 8 embryos range in diameter from approximately 130-1300 µm, with embryos smaller than 300 µm reported to suffer an increased incidence of EEL. However, it is not known whether this reduced viability is due to intrinsically poor embryo quality, or to inadvertent recipient uterine stage-embryo (positive) asynchrony. To examine whether small embryos survive better in Day 4-5 recipients than in recipients with a more advanced uterine stage, the likelihood of pregnancy (PR) and EEL for 62 small (<300 µm) and 215 larger Day 8 horse embryos were compared after transfer to recipients at different uterine stages (Days 4-5, 6-7 and 8-9) using logistic regression. Overall, EEL was higher (21.2%; P < 0.05) for small than larger embryos (7.1%). However, neither PR nor EEL were influenced by the recipient's uterine stage at the time of transfer (P > 0.1). The EEL for small embryos transferred into Day 4-5, 6-7 and 8-9 recipients was 20.8, 18.7 and 25.0%, respectively. We conclude that embryos recovered on Day 8 with a diameter <300 µm are at increased risk of EEL due to reasons other than inadvertent positive asynchrony with the recipient mare's uterus.

Manejo diagnóstico-terapéutico de las lesiones mamarias atípicas / Diagnostic-therapeutic Management of Atypical Breast Lesions

Las lesiones mamarias se dividen histológicamente en dos grandes grupos, malignas y benignas. Las lesiones malignas pueden ser de origen ductal o lobulillar, siendo el carcinoma ductal infiltrante la neoplasia invasiva más frecuente. Las lesiones benignas se clasifican en no proliferativas, proliferativas sin atipias y proliferativas con atipias. Dentro de los dos últimos grupos se encuentran entidades que conllevan un alto riesgo de desarrollar carcinoma de mama, como pueden ser la hiperplasia ductal atípica, la cicatriz radial o la neoplasia lobular. Revisamos en qué consisten dichas entidades y cuáles son sus características principales en imagen, fundamentalmente en mamografía y ecografía. Si tras realizar una biopsia se obtiene uno de esos diagnósticos histológicos, es importante analizar las características imagenológicas y el tipo de procedimiento realizado (número de cilindros obtenidos, calibre de aguja...), para realizar un adecuado manejo posterior. En algunos casos la actitud a seguir será la extirpación quirúrgica completa de la lesión, mientras que en otros se podrá realizar una extirpación percutánea (mediante biopsia con aguja de vacio), o incluso seguimiento estricto por imagen. Mediante diferentes casos mostraremos nuestra experiencia y analizaremos la literatura vigente para recordar esas entidades y llegar a un consenso adecuado sobre el manejo de las mismas.

Breast lesions are divided histologically into two large groups, malignant and benign. Malignant lesions may be of ductal or lobular origin, with infiltrating ductal carcinoma being the most frequent invasive neoplasm. Benign breast lesions are classified as proliferative, proliferative without atypia and proliferative with atypia. Within the last two classifications are entities that carry a high risk of developing breast carcinoma, such as atypical ductal hyperplasia, radial scar or lobular neoplasia. We review what these entities consist of and what are their fundamental characteristics in image, fundamentally in mammography and ultrasound. When we perform one of these histological diagnoses after a biopsy, it is important to analyze the radiological characteristics and the type of procedure performed (number of cylinders, needle gauge ...) to perform an appropriate posterior management. In some cases the attitude to be followed will be the complete surgical removal of the lesion, while in others a percutaneous excision (through vacuum needle biopsy) or even strict image follow-up may be performed. Through different cases we will show our experience and analyze current literature to remember these entities and reach an adequate management consensus.

Horse embryo diameter is influenced by the embryonic age but not by the type of semen used to inseminate donor mares.

The diameter of embryos recovered from mares on Day 8 after ovulation varies greatly, from as little as 130 µm to as much as 2500 µm. Several factors have been proposed to affect embryo size at recovery, one of which is the type of semen (frozen vs fresh or cooled-transported) used to inseminate the mare. In addition, it has been shown that smaller embryos (<300 µm) recovered on Day 8 are less likely than larger embryos to result in successful pregnancy after transfer. However, whether the actual age of the embryo (interval from fertilization to flushing) in relation to its size also influences the post-transfer viability is unclear. The aims of this study were: a) To determine the effect of semen type (frozen-thawed vs cooled-transported) on embryo diameter after pre-ovulatory insemination; and b) To establish the relationship between embryonic age, embryo size and likelihood of pregnancy and pregnancy loss following transfer. A total of 179 embryos were recovered from mares inseminated with: frozen semen post-ovulation 8 days previously (G1; n = 35); cooled-transported semen pre-ovulation 8.5 days previously (G2; n = 95); frozen semen pre-ovulation 8.5 days previously (G3; n = 30); and frozen semen post-ovulation 9 days previously (G4; n = 19). The effect of embryonic age, type of semen, donor mare and its age, number of ovulations and embryos per flush on embryo diameter was tested using a general linear model of variance. In addition, the proportions and survivals of small embryos (<300 µm) in each group were compared with those of respective larger embryos by Fisher's exact test. Embryonic age (P < 0.001) and age of the donor mare (P = 0.07), but no other factor, influenced embryo diameter. The proportion of small embryos was 42.9, 10.5, 10.0 and 10.5% for Groups 1, 2, 3 and 4, respectively. The pregnancy status of recipient mares 35 days post-transfer for small embryos from Group 1 (12/15; 80.0%) was not different (P > 0.1) from that of recipients of small embryos from Groups 2 to 4 combined (8/15; 53.3%).

Validated quantitative trait loci for eggshell quality in experimental and commercial laying hens.

Compromised eggshell quality causes considerable economic losses for the egg industry. Breeding for improved eggshell quality has been very challenging. Eggshell quality is a trait that would greatly benefit from marker-assisted selection, which would allow the selection of sires for their direct contribution to the trait and would also allow implementation of measurements integrating a number of shell parameters that are difficult to measure. In this study, we selected the most promising autosomal quantitative trait loci (QTL) affecting eggshell quality on chromosomes 2, 3, 6 and 14 from earlier experiments and we extended the F2 population to include 1599 F2 females. The study was repeated on two commercial populations: Lohmann Tierzucht Rhode Island Red line (n = 692 females) and a Hy-Line White Plymouth Rock line (n = 290 progeny tested males). We analyzed the selected autosomal QTL regions on the three populations with SNP markers at 4-13 SNPs/Mb density. QTL for eggshell quality were replicated on all studied regions in the F2 population. New QTL were detected for eggshell color on chromosomes 3 and 6. Marker associations with eggshell quality traits were validated in the tested commercial lines on chromosomes 2, 3 and 6, thus paving the way for marker-assisted selection for improved eggshell quality.

Likelihood of pregnancy after embryo transfer is reduced in recipient mares with a short preceding oestrus.

BACKGROUND: Previous surveys reported a positive association between the length of the follicular phase and subsequent fertility in embryo transfer donor and Thoroughbred mares. However, it is unclear whether a longer oestrus positively influences fertilisation and oviductal development (oocyte quality, oviductal environment), or uterine receptivity and survival of the embryo in the uterus. OBJECTIVES: To determine the effect of length of oestrus (characterised by duration of endometrial oedema) on likelihood of pregnancy and early embryo loss (EEL) in recipient mares after embryo transfer (ET). STUDY DESIGN: Retrospective clinical study. METHODS: A total of 350 embryos recovered from 161 donor mares were transferred into 231 recipient mares during three consecutive breeding seasons. The following variables were analysed via two binary logistic regression models to determine their effect on pregnancy and EEL: 1) year of transfer, 2) season of transfer, 3) age of the recipient mare, 4) age of the donor mare, 5) operator performing the transfer, 6) singleton or twin embryo, 7) embryo size, 8) number of transfers to a given recipient in any one season, the use of 9) d-cloprostenol and 10) hCG in the recipient mare, 11) day of ovulation of the recipient mare at ET, 12) number of corpora lutea (CLs) at ET, and 13) duration of oestrus in the recipient mare. RESULTS: Age of the donor mare (P = 0.01), operator (P = 0.008), number of CLs at ET (P = 0.05) and the number of days of endometrial oedema during the oestrus preceding ET to the recipient mare (P = 0.004) influenced the likelihood of pregnancy. Early embryonic loss was influenced only by the year of transfer (P = 0.014). MAIN LIMITATIONS: Retrospective design of the study. The involvement of several veterinary surgeons over the 3-year period could have affected data recording. CONCLUSIONS: The likelihood of pregnancy in recipient mares is positively correlated with the duration of endometrial oedema during the oestrus preceding ET. This suggests a role for an adequate duration of oestrogenic priming during oestrus on uterine receptivity and embryo survival.

Gallbladder Mucocele: Variables Associated with Outcome and the Utility of Ultrasonography to Identify Gallbladder Rupture in 219 Dogs (2007-2016).

BACKGROUND: Gallbladder mucocele (GBM) is an increasingly recognized extrahepatic biliary disease in dogs. OBJECTIVES: To investigate cases of GBM and identify variables associated with survival and the sensitivity and specificity of ultrasonography to identify gallbladder rupture. ANIMALS: Two hundred and nineteen client-owned dogs with GBM. METHODS: Multicenter, retrospective study of dogs with GBM, presented from January 2007 to November 2016 to 6 academic veterinary hospitals in the United States. Interrogation of hospital databases identified all cases with the inclusion criteria of a gross and histopathologic diagnosis of GBM after cholecystectomy and intraoperative bacteriologic cultures of at least 1 of the following: gallbladder wall, gallbladder contents, or abdominal effusion. RESULTS: Two hundred and nineteen dogs fulfilled the inclusion criteria. Dogs with GBM and gallbladder rupture with bile peritonitis at the time of surgery were 2.7 times more likely to die than dogs without gallbladder rupture and bile peritonitis (P = 0.001; 95% confidence interval [CI], 1.50-4.68; n = 41). No significant associations were identified between survival and positive bacteriologic cultures, antibiotic administration, or time (days) from ultrasonographic identification of GBM to the time of surgery. The sensitivity, specificity, positive, and negative likelihood ratios for ultrasonographic identification of gallbladder rupture were 56.1% (95% CI, 39.9-71.2), 91.7% (95% CI, 85.3-95.6), 6.74, and 0.44, respectively. CONCLUSION AND CLINICAL IMPORTANCE: Dogs in our study with GBM and intraoperative evidence of gallbladder rupture and bile peritonitis had a significantly higher risk of death. Additionally, abdominal ultrasonography had low sensitivity for identification of gallbladder rupture.