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Colonial waterbirds such as herons, egrets and spoonbills exhibit ecological characteristics that could have promoted the evolution of conspecific brood parasitism and extra-pair copulation. However, an adequate characterization of the genetic mating systems of this avian group has been hindered by the lack of samples of elusive candidate parents which precluded conducting conventional parentage allocation tests. Here, we investigate the genetic mating system of the invasive cattle egret using hematophagous insects contained in fake eggs to collect blood from incubating adults in a wild breeding colony. We tested a protocol with a previously unused Neotropical Triatominae, Panstrongylus megistus, obtained blood samples from males and females in 31 nests built on trees, drew blood from 89 nestlings at those nests, and genotyped all samples at 14 microsatellite loci, including six new species-specific loci. We comparatively addressed the performance of parentage allocation versus kinship classification of nestlings to infer the genetic mating system of cattle egrets. In line with previous behavioral observations, we found evidence in support of a non-monogamous genetic mating system, including extra-pair paternity (EPP) and conspecific brood parasitism (CBP). Parentage allocation tests detected a higher percentage of nests with alternative reproductive tactics (EPP: 61.7%; CBP: 64.5%) than the kinship classification method (EPP: 50.0%; CBP: 43.3%). Overall, these results indicate that rates of alternative reproductive tactics inferred in the absence of parental genetic information could be underestimated and should be interpreted with caution. This study highlights the importance of incorporating samples from candidate parents to adequately determine the genetic mating system of a species. We expand knowledge on the reproductive tactics of colonial waterbirds, contributing novel data on the genetic mating system of the cattle egret, valuable for the design of management strategies for this invasive bird. [ABSTRACT FROM AUTHOR]

Background: Commercial cuts yield is an important trait for beef production, which affects the final value of the products, but its direct determination is a challenging procedure to be implemented in practice. The measurement of ribeye area (REA) and backfat thickness (BFT) can be used as indirect measures of meat yield. REA and BFT are important traits studied in beef cattle due to their strong implication in technological (carcass yield) and nutritional characteristics of meat products, like the degree of muscularity and total body fat. Thus, the aim of this work was to study the Longissimus dorsi muscle transcriptome of Nellore cattle, associated with REA and BFT, to find differentially expressed (DE) genes, metabolic pathways, and biological processes that may regulate these traits. Results: By comparing the gene expression level between groups with extreme genomic estimated breeding values (GEBV), 101 DE genes for REA and 18 for BFT (false discovery rate, FDR 10%) were identified. Functional enrichment analysis for REA identified two KEGG pathways, MAPK (Mitogen-Activated Protein Kinase) signaling pathway and endocytosis pathway, and three biological processes, response to endoplasmic reticulum stress, cellular protein modification process, and macromolecule modification. The MAPK pathway is responsible for fundamental cellular processes, such as growth, differentiation, and hypertrophy. For BFT, 18 biological processes were found to be altered and grouped into 8 clusters of semantically similar terms. The DE genes identified in the biological processes for BFT were ACHE, SRD5A1, RSAD2 and RSPO3. RSAD2 has been previously shown to be associated with lipid droplet content and lipid biosynthesis. Conclusion: In this study, we identified genes, metabolic pathways, and biological processes, involved in differentiation, proliferation, protein turnover, hypertrophy, as well as adipogenesis and lipid biosynthesis related to REA and BFT. These results enlighten some of the molecular processes involved in muscle and fat deposition, which are economically important carcass traits for beef production. [ABSTRACT FROM AUTHOR]

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a smartphone, which contains an accelerometer, a gyroscope, a magnetometer and location sensors signals sampled at 100 Hz. This equipment was mounted on 19 grazing cows of different breeds and daily video sequences were recorded on pasture of different forage allowances. After visually analyzing the cows’ movements on a calibration database, signal combinations were selected and thresholds were determined based on 1-s time windows, since increasing the time window did not increase the accuracy of detection. The final algorithm uses the average value and standard deviation of two signals in a two-step discrimination tree: the gravitational acceleration on x-axis (Gx) expressing the cows’ head movements and the rotation rate on the same x-axis (Rx) expressing jaw movements. Threshold values encompassing 95% of the normalized calibrated data gave the best results. Validation on an independent database resulted in an average detection accuracy of 92% with a better detection for rumination (95%) than for grass intake (91%). The detection algorithm also allows for characterization of the diurnal feeding activities of cattle at pasture. Any user can make further improvements, for data collected at the same way as the iPhone’s IMU has done, since the algorithm codes are open and provided as supplementary data . [ABSTRACT FROM AUTHOR]

Recently, dysfunction of antigen-specific T cells is well documented as T-cell exhaustion and has been defined by the loss of effector functions during chronic infections and cancer in human. The exhausted T cells are characterized phenotypically by the surface expression of immunoinhibitory receptors, such as programmed death 1 (PD-1), lymphocyte activation gene 3 (LAG-3), T-cell immunoglobulin and mucin domain-containing protein 3 (Tim-3) and cytotoxic T-lymphocyte antigen 4 (CTLA-4). However, there is still a fundamental lack of knowledge about the immunoinhibitory receptors in the fields of veterinary medicine. In particular, very little is known about mechanism of T cell dysfunction in chronic infection in cattle. Recent our studies have revealed that immunoinhibitory molecules including PD-1/programmed death-ligand 1 (PDL1) play critical roles in immune exhaustion and disease progression in case of bovine leukemia virus (BLV) infection, Johne's disease and bovine anaplasmosis. This review includes some recent data from us. [ABSTRACT FROM AUTHOR]

Feed efficiency, simply expressed as less feed inputs versus animal production outputs, can be measured in several ways, such as feed conversion ratio (FCR) and residual feed intake (RFI). FCR is a common measurement in beef cattle operations, and is the ratio of feed intake to live-weight gain. RFI is defined as the difference between actual and predicted feed intake after taking into account variability in maintenance and growth requirements. Rumen microbiota, which inludes bacteria, archaea, protozoa, and fungi, play an essential role in the digestion of lignocellulosic plant biomass, and can provide more than 70% of the host ruminants energy requirements via the production of volatile fatty acids (VFAs). Methane, a potent greenhouse gas (GHG), is produced in large quantities by the rumen microbiota, and is a known contributor to the global increase in GHG emissions. Studies have shown a negative relationship between methane emission and feed efficiency. Therefore, there is a need to study the feed efficiency from a rumen microbiome perspective and explore the probability of improving feed efficiency and hence reduce methane production in cattle by manipulating the rumen microbiome. The development of highthroughput sequencing technologies incuding metagenomics and metatranscriptomic analyses in the past decade has led to a sharp increase in understanding the rumen microbiota and associated function. As such, this mini-review will focus on the new findings during the last decade in cattle feed efficiency and the rumen microbiome. [ABSTRACT FROM AUTHOR]

A participatory epidemiological (PE) study was conducted with livestock keepers in Moroto and Kotido districts, Karamoja Region, Uganda, between October and December 2013 to determine the management options and relative importance of tick-borne diseases (TBDs) amongst transhumant zebu cattle. Data collection involved 24 focus group discussions (each comprising 8–12 people) in 24 settlement areas (manyattas), key informant interviews (30), direct observation, a review of surveillance data, clinical examination, and laboratory confirmation of cases of TBDs. Methods used in group discussions included semi-structured interviews, simple ranking, pairwise ranking, matrix scoring, proportional piling and participatory mapping. The results of pairwise comparison showed the Ngakarimojong-named diseases, lokit (East Coast fever, ECF), lopid (anaplasmosis), loukoi (contagious bovine pleuropneumonia, CBPP), lokou (heartwater) and lokulam (babesiosis), were considered the most important cattle diseases in Moroto in that order, while ECF, anaplasmosis, trypanosomosis (ediit), CBPP and nonspecific diarrhoea (loleo) were most important in Kotido. Strong agreement between informant groups (Kendall’s coefficient of concordance W = 0.568 and 0.682; p < 0.001) in pairwise ranking indicated that the diseases were a common problem in selected districts. East Coast fever had the highest median score for incidence (18% [range: 2, 33]) in Moroto, followed by anaplasmosis (17.5% [8,32]) and CBPP (9% [1,21]). Most animals that suffered from ECF, anaplasmosis, heartwater and babesiosis died, as the respective median scores for case fatality rates (CFR) were 89.5% (42, 100), 82.8% (63, 100), 66.7% (20, 100) and 85.7% (0, 100). In Kotido, diseases with high incidence scores were ECF (21% [6,32]), anaplasmosis (17% [10,33]) and trypanosomosis (8% [2,18]). The CFRs for ECF and anaplasmosis were 81.7% (44, 100) and 70.7% (48, 100), respectively. Matrix scoring revealed that disease indicators showed strong agreement ( W = 0.382–0.659, p < 0.05– p < 0.001) between informant groups. Inadequate knowledge, poor veterinary services and limited availability of drugs were the main constraints that hindered the control of TBDs. Hand picking of ticks was done by all pastoralists while hand spraying with acaricides was irregular, often determined by availability of drug supplies and money. It was concluded that TBDs, particularly ECF and anaplasmosis were important diseases in this pastoral region. Results from this study may assist in the design of feasible control strategies. [ABSTRACT FROM AUTHOR]

Objective To identify patterns of cattle movement that could influence disease spread in the Australian cattle population. Methods Records from the National Livestock Identification System database for the period January 2008 to December 2012 were accessed and analysed. Postcodes were used to allocate each individual property to one of 12 livestock production regions. National movement patterns and the characteristics of each livestock production region were quantified in terms of the number of consignments and animals moved, and seasonality of movements. Results The majority of cattle movements remained within a single livestock production region, while those that did not, usually remained within the same state or territory. Producers were the most common source of cattle, and abattoirs and other producers the most common destinations, with approximately 40% of animals moving via a saleyard. The northern regions generally moved larger consignments than the southern regions and were less connected to other regions. The eastern and south-eastern regions were very well connected by cattle movements. Seasonal patterns were seen for some regions, particularly the northern regions where weather patterns strongly influence the ability of producers to muster and transport stock. Conclusions The movement patterns observed provide quantitative support for previous information based on surveys and expert opinion, and capture more of the variability in Australian cattle production. This information may assist with management of animal disease risks, in particular exotic diseases, and in planning surveillance programs. [ABSTRACT FROM AUTHOR]

This study characterizes the physiological and morphological changes related to partial luteolysis in bovine corpus luteum (CL) after challenges with sub-doses of cloprostenol sodium on Day 6 (D6) of the estrous cycle. Cows ( n = 12/treatment) were treated as follows: Control (2 mL, saline, i.m.); 2XPGF (two treatments i.m. 500 μg of cloprostenol sodium 2 h apart) and 1/6PGF (83.3 μg of cloprostenol sodium, i.m., once). Plasma progesterone (P4) concentration, CL volume and blood flow were measured immediately before the treatments, then every 8 h (h) for 48 h. In the Control, P4 concentrations were higher at 48 h than at 0 h. P4 decreased 8 h after 2XPGF treatment ( P < 0.05), and remained low until the end of the trial. P4 decreased in 1/6PGF between 8 and 16 h ( P < 0.05), then began to rebound at 24 h. Luteal volume was higher in Controls at 48 h than at 0 h. Under 1/6PGF, luteal volume decreased at 24 h ( P < 0.05) and began to rebound at 32 h. Luteal volume and blood flow were reduced starting at 24 and 32 h, respectively, after 2XPGF treatment ( P < 0.05). In this study, we were able to describe the partial luteolysis phenomenon, induced by a treatment of a D6CL with cloprostenol sub-dose. [ABSTRACT FROM AUTHOR]

The movements of replacement breeding cattle have been implicated in the spread of many economically important cattle diseases. In this analysis, records from the Cattle Tracing System database were used to investigate the frequency and characteristics of replacement breeding cattle trade in Great Britain. During the 2006 calendar year, an estimated 48.7 per cent of beef herds and 47.8 per cent of dairy herds purchased at least one replacement breeding animal. Open beef herds purchased an average of 7.2 replacement animals (median: 4, range: 1-819) from 3.6 source herds (median: 2, range: 1-114), while open dairy herds purchased an average of 13.7 replacement animals (median: 7, range: 1-827) from 5.2 source herds (median: 3, range: 1-146). The most common animal types purchased by beef and dairy herds were open heifers and open lactating cows, respectively. Although the movements of purchased replacement breeding cattle accounted for only 13 per cent of individual movements in the between-herd contact network, they had a disproportionately strong influence on the risk of disease spreading through the industry as evidenced by their high betweenness centrality scores. These results emphasise the importance of ensuring that good biosecurity programmes are in place to prevent disease transmission. [ABSTRACT FROM AUTHOR]

A 4-yr study integrating pasture and drylot feeding systems was used to assess cultural energy analysis of cattle production systems. Each year, 116 fall-born Hereford and Angus crossbred calves of similar genotypes were used. The calves were obtained April 15 following weaning and a preconditioning program. Following a 2-wk acclimation period in a drylot on ground midbloom alfalfa hay, the calves were assigned to treatmerits by weight and color pattern. Treatments were 1) placing calves onbromegrass pasture until mid October, at which time they were removed and finished in a drylot (OCT); 2) placing calves on bromegrass pasture until approximately July 1, at which time they were moved to a drylot for finishing; 3) placing calves on bromegrass pasture until mid June, at which time they were moved to warm-season pastures until being returned to bromegrass pasture from mid August until sometime in October when they were placed in a drylot for finishing (WARM); and 4) placing 28 steers directly into a drylot at the start of the tests (FEEDLOT). The bromegrass pasture consisted of 24 paddocks, each 1.7 acres in size. Each grazing treatment of 28 steers (except for 32 steers placed on warm-grass pastures) was rotated among paddocks at 3- to 4-d intervals early in the season and at about 2-d intervals later in the season. An 82% concentrate diet containing whole shelled corn, ground alfalfa hay, and a protein-vitamin mineral supplement with ionophores and molasses was provided ad libitum daily in the drylot. On pasture, calves were provided supplement blocks containing ionophores. Pens of cattle were harvested at approximately 568 kg. Cultural energy used for pasture establishment, feed consumption, and maintenance were calculated using the actual inputs and corresponding energy values from the literature. The FEEDLOT cattle had higher and OCT cattle had lower total cultural energy expenditures than other treatments (P < 0.01). Feed energy made up more than half of the total cultural energy and was highest for FEEDLOT cattle and was lowest for OCT cattle (P < 0.01). Energy expended per kilogram live weight gain was higher for FEEDLOT cattle (P < 0.01). The energy output ratio, defined by kilocalories input/ kilocalories output, was better for the OCT treatment followed by the WARM treatment (P < 0.01). Results show that pasturing cattle is an effective way of reducing cultural energy expenditure and that grazing cool-season grass was better suited to the concept of sustainable agriculture. [ABSTRACT FROM AUTHOR]