Dual-purpose Cattle Research Articles

Does Gender Impact Technology Adoption in Dual-Purpose Cattle in Mexico?

This paper examines the role of women in the dual-purpose livestock system (DP) in Mexico through their technological adoption patterns and aims to evaluate whether there are significant differences between the technology adoption networks of men and women farmers. The sample was composed of 383 DP small farms with 20 or fewer cows and a high level of vulnerability. Social Network Analysis (SNA) was applied, and the centrality measures were calculated for the technological areas of management, feeding, genetics, reproduction, and animal health. Significant differences were found in reproduction levels between men and women farmers. Therefore, SNA was developed in this technological area where men mainly occupied central positions (brokers) while women were just close to the leaders in the network. The results have shown that farms run by women were smaller and presented higher levels of specialization and milk productivity (20% higher), and women prioritized those technologies linked to female reproductive efficiency. Moreover, women were deeply embedded in men's networks through numerous ties and were capable of building connections with groups of farmers outside of their own group.

Nutritional assessment of tropical pastures as a sustainability strategy in dual-purpose cattle ranching in the South of Lake Maracaibo, Venezuela

Pastures represent the greatest sustainability challenge for tropical cattle, as they are fibrous pastures, low in protein, with few soluble carbohydrates and limited digestibility. To evaluate the nutritional quality of tropical pastures, during the rainy and dry season a farm dedicated to raising dual-purpose cattle in the South of Lake Maracaibo-Venezuela was visited; there, six paddocks dominated by grasses adapted to the ecological conditions of the tropical humid rainforest were randomly selected. The sampling consisted of collecting, simulating the selective biting pattern of the animal, all the forage biomass found in 1 m 2 delimited by a metal frame that was thrown on several occasions until covering the grazing area. A final composite sample was made for each paddock, which were weighed and analyzed to determine parameters of nutritional interest. The study revealed that the paddock as a source of variation affected (P < 0.05) the floristic composition of the pastures, while the highest yield of consumable green matter, dry matter, crude protein, ether extract, ash and nitrogen-free extract was recorded during the rainy season (P < 0.05); however, there was no significant effect (P > 0.05) of the season on the content of total digestible nutrients, neutral detergent fiber and acid detergent fiber. The results suggest intensifying grazing during the wettest season and incorporating a gradual fertilization plan that guarantees higher forage biomass during the drought.

Factor Analysis of Genetic Parameters for Body Conformation Traits in Dual-Purpose Simmental Cattle.

Simple SummaryBody conformation traits are closely related to economically important characteristics and should be considered in cattle breeding programs. A variety of body conformation traits recorded by classifiers can complicate the analysis process. Factor analysis can reduce the number of variables by combining two or more variables into a single factor, which has biological significance. The results of this study could be used by breeders to define conformation indexes and implement genetic assessments for conformation traits in dual-purpose breeds.In this study, we estimated the genetic parameters for 6 composite traits and 27 body conformation traits of 1016 dual-purpose Simmental cattle reared in northwestern China from 2010 to 2019 using a linear animal mixed model. To integrate these traits, a variety of methods were used as follows: (1) genetic parameters estimates for composite and individual body conformation traits based on the pedigree relationship matrix (A) and combined genomic-pedigree relationship matrix (H); (2) factor analysis to explore the relationships among body conformation traits; and (3) genetic parameters of factor scores estimated using A and H, and the correlations of EBVs of the factor scores and EBVs of the composite traits. Heritability estimates of the composite traits using A and H were low to medium (0.07–0.47). The 24 common latent factors explained 96.13% of the total variance. Among factors with eigenvalues ≥ 1, F1 was mainly related to body frame, muscularity, and rump; F2 was related to feet and legs; F3, F4, F5, and F6 were related to teat placement, teat size, udder size, and udder conformation; and F7 was related to body frame. Single-trait analysis of factor scores yielded heritability estimates that were low to moderate (0.008–0.43 based on A and 0.04–0.43 based on H). Spearman and Pearson correlations, derived from the best linear unbiased prediction analysis of composite traits and factor scores, showed a similar pattern. Thus, incorporating factor analysis into the morphological evaluation to simplify the assessment of body conformation traits may improve the genetics of dual-purpose Simmental cattle.

IDENTIFICACIÓN TAXONÓMICA DE Mocis latipes Guenée (LEPIDOPTERA: EREBIDAE) EN PASTOS FORRAJEROS DE VERACRUZ, MÉXICO

&lt;p&gt;&lt;strong&gt;Background.&lt;/strong&gt; Cultivation of forage grasses is an important component in the dual-purpose cattle production system; however, insect pests can decrease fresh material yields. &lt;strong&gt;Objective. &lt;/strong&gt;To taxonomically identify the causal agent that damages the cultivars &lt;em&gt;Panicum maximum &lt;/em&gt;(Jacq.) cv. Mombasa and&lt;em&gt; Panicum maximum &lt;/em&gt;cv. Zuri. &lt;strong&gt;Methodology.&lt;/strong&gt; In two locations in the central region of Veracruz, specimens of an insect in the larval and pupal stages were collected using the quadrant method in an area of 50 ha. Subsequently, in the laboratory, larvae were boiled for two minutes and preserved in 70% alcohol. Meanwhile, pupae were placed in a brood chamber with foliage to obtain adults and to extract their genitalia, which represents the most important morphological structure for the identification of a species. &lt;strong&gt;Results.&lt;/strong&gt; The total number of collected larvae was 650, and 65 pupae, all reaching the adult stage. Based on the taxonomic morphology, the species &lt;em&gt;Mocis latipes&lt;/em&gt; or striped grassworm was determined. Damage was estimated at approximately 40% per hectare.&lt;strong&gt; Implications.&lt;/strong&gt; Correct identification of the pest insect allows the implementation of a strategy for proper management. &lt;strong&gt;Conclusion.&lt;/strong&gt; The species&lt;em&gt; M. latipes&lt;/em&gt; was identified in forage grasses &lt;em&gt;P. maximum&lt;/em&gt; cv. Mombasa and &lt;em&gt;P. maximum &lt;/em&gt;cv. Zuri in Veracruz.&lt;/p&gt;

Development and application of arachnomelia syndrome genetic detection in four Chinese dual-purpose cattle populations

Arachnomelia syndrome (AS) is an autosomal recessive hereditary disorder in cattle, and affected calves are usually stillborn and characterized by complex anomalies. Therefore, identification of the carrier animals based on genetic tests is important for the control and elimination of this defect. The aim of this study was to build an effective workflow to routinely screen the AS mutations in bovine MOSC1 and SUOX genes and determine individuals carrying the AS mutations in four Chinese cattle populations.By combining the fluorescence-labeled PCR and capillary electrophoresis, we established a convenient and cost-effective workflow to detect two AS casual mutations simultaneously. Sanger sequencing was further used as a validation criterion and showed that 100% of the tests (37/37) had consistent results with genotype calls determined by our established workflow. Then, 582 bulls and 1-926 cows from Chinese dual-purpose cattle populations of Simmental, Sanhe, Shuxuan, and Xinjiang Brown were subjected to AS detection. The results showed that four bulls and 11 cows in the Simmental population, and six bulls and six cows in the Sanhe population were identified as AS carriers with the MOCS1 mutation c.1224_1225delCA. However, no animal was found to carry the c.363_364insG mutation in the SUOX gene. The frequencies of AS carriers were 1.08% and 1.65% in the Simmental and Sanhe populations, respectively, with a frequency of 1.076% in four populations. The pedigree analysis found that all carriers could be traced back to a common ancestor, the German Simmental sire ROMEL. Those findings suggested that this genetic defect spread into China mainly through the wide use of ROMEL. In conclusion, the occurrence of AS has not had a wide impact on the Chinese cattle industry; however, a screening system and mating strategy should be employed to gradually eliminate this recessive gene from the Chinese dual-purpose cattle population.

Milk, meat, and human edible protein from dual-purpose cattle in Costa Rica: Impact of functional unit and co-product handling methods on predicted enteric methane allocation

In many developing countries, milk and meat produced from dual-purpose cattle systems contribute substantially to the national supply of animal-derived human-edible protein (HEP). Defining a main product and a co-product may be difficult in these diversified systems because of the large spatial variation and possibly rapid temporal variation in the contribution of each product within a farm and among farms. Few studies have investigated the impact of the milk-to-meat ratio output of cattle systems of developing countries on allocation of greenhouse gases when using Life Cycle Assessment (LCA). In this study, we analysed data collected from 677 Costa Rican farms with the objectives of 1) developing a field-based methodological framework to quantify the contribution of milk, meat, and HEP from milk and meat in dual-purpose systems relevant to developing countries, and 2) evaluating the effect of the functional unit (FU), co-products handling methods, and milk-to-meat ratio on how predicted enteric methane (CH4) would be allocated in an LCA of dual-purpose systems of contrasting orientation (towards beef vs. towards dairy). Farms were categorized based on farmer-reported farm income from milk sales relative to income from both milk and animal sales: Beef (BS; <1%), Dual-purpose towards beef (DP-B; 1–39%), Dual-purpose with dairy and beef in similar proportion (DP-DB; 40–59%), Dual-purpose towards dairy (DP-D; 60–89%), and Dairy (DS; 90–100%). Enteric CH4 emission was predicted from reported herd structure and emission factors per animal category (adult female, adult male, heifer and steer), and allocated to milk as the main product (FU = 1 kg of milk) with meat as a co-product or reported per kg of HEP. To allocate emissions to milk and meat, we used the following methods: (a) All-to-milk, (b) mass-based, (c) biological-based, and (d) system expansion. Milk and HEP production were significantly greater in DS compared to other systems. Emission attributed to milk varied from 66% to 100% when using all-to-milk, mass-based, and biological allocation methods but from −1% to 44% when using system expansion. Low productivity and high emission intensity of meat for the alternative system, leading to unrealistically high meat emission deduction, explained the substantially lower percentage of emission attributed to milk for system expansion compared to the other methods. All-to-milk and mass-based allocation methods were insensitive to change in milk-to-meat ratio of the system but increasing ratio altered substantially the partitioning of emission between milk and meat when using biological allocation and system expansion. Depending on the allocation method used, the imputed emission intensity of meat varied from zero (all-to-milk) to 13.4 kg carbon dioxide equivalent (CO2-eq) as CH4/ kg of meat (system expansion). Using HEP does not capture the importance of other nutrients in animal source foods but helped resolve LCA methodological issues of concern for dual-purpose cattle systems of developing countries.

Bio-economic models for deriving economic values for cattle: a review

Abstract. Bio-economic models for deriving economic weights in livestock have a significant development in recent years providing integrated assessment of biological and economic parameters of production systems and possibilities for achieving economic sustainability through inclusion in the selection index. Economic weights (EW) of traits have been calculated for different species of farm animals in the years. However, this review focuses on large ruminant aiming to summarize studies on calculation of economic values for dairy, beef and dual-purpose cattle. A method of research selection was used according to the productive direction (for milk, meat and dual-purpose), as well as according to the studied traits. In conclusion, it could be summarized that with regard to breeding objectives, economic weights of breeding traits need to be recalculated at certain time-periods and redefined in order to be relevant to the current market situations. Recently, there has been a tendency for functional traits to have an increasing economic influence and some of them should be included in the breeding goal. Moreover, the increased interest among customers in animal welfare and quality of dairy farm products will probably lead to the incorporation of health traits as clinical mastitis incidence and somatic cells score in the breeding objective. It is possible as well the relative importance of feed efficiency traits to increase in the future due to increasing requirements to mitigate the environmental impact of production systems.

Characterization of tropical cattle production units: Effect of sanitary management

Objective: To characterize dual-purpose cattle production units (PUs) and to identify the sanitary management that producers use with their herds. Design/Methodology/Approach: Sixty (60) cattle producers were interviewed; the questions were related to the characteristics of the PU and the sanitary status. Four serum samples from the largest herd were sent to the laboratory to detect diseases. Results: All the cattle producers surveyed were men between 20 and 50 years old. Of them, 40% have been devoted to the activity for 11 to 25 years. The PUs have on average 25 animals, 45% of producers have between 21 and 30 cows, and the highest percentage of animals are breeds Gyr (35%) and Sardo Negro (30%). Of producers, 65% tend to their sick animals. On the other hand, the laboratory studies showed that three cows were positive for Bovine Respiratory Syncytial Virus (BRSV), two cows were positive for type 1 bovine herpes virus (BoHV-1), or Infectious Bovine Rhinotracheitis (IBR) and parainfluenza 3 (PI3), and finally all the cows were positive for Leptospira sp. Hardjo. Study Limitations/Implications: Under the conditions in which the study was conducted, it is costly to send samples to the laboratory. The producer with the largest herd financed the laboratory tests of the cows sampled. This information is useful for local producers with regards to the characteristics in which they produce them. Findings/Conclusions: Dual-purpose cattle producers in the tropics produce at a small scale; and one of the largest PUs presents problems of abortive diseases.

Growth ability of Czech Fleckvieh bulls in modern cattle fattening stable

ABSTRACT The work aimed to evaluate the growth ability of Czech Fleckvieh bulls in the conditions of modern stable based on their breeding lines. A total of 94 bulls were included in the experiment. The growth curve, weight at standardized ages, and weight gain were evaluated. The average weight of fattened bulls ranged from 109.43 kg at the age of 90 days to 705.65 kg at the end of the fattening period. Statistically significant model function was created by regression analysis and included the effects of bull sire, peers, age, and age squared. Furthermore, we used a linear model with the effects: birth month of the bull, the group of peers, the breeding line of bull sire, and random repeated effect of the animal. Significant differences were observed for the month of birth and between groups of peers. The effect of the breeding line was significant for regression analysis, however in evaluation based on linear model it was significant only for the weight at the beginning of fattening. The results suggest that in the standardized conditions of a modern stable with good housing and nutrition, the genetic predisposition for the growth ability of dual-purpose Fleckvieh cattle was attenuated.

Conservation of local Red cattle breeds by collaboration with a mainstream Red dairy cattle breed

Numerous Red cattle breeds exist all throughout Europe. Some Red cattle breeds are only used locally in certain regions and are smaller in population size, whereas other Red cattle breeds are used in multiple countries in mainstream production environments. Conservation of local Red breeds is necessary to maintain genetic diversity. Collaboration between local and mainstream Red cattle breeds can increase the genetic potential of the local breed and thereby the success of survival. The aim of this paper was to explore possibilities to increase the genetic potential of local Red cattle breeds by collaboration with a mainstream Red cattle breed, while at the same time conserve the local Red cattle breeds. Three breeds were included in this study; the mainstream Red dairy cattle breed from Denmark, Finland and Sweden (RDC) and two local Red cattle breeds, German Red and White dual-purpose cattle (RDN), and Lithuanian Red (LIR). Each simulation included the RDC breeding program and one local Red breeding program. Simulated time was 30 years, in which the first 20 years were used to build up reference populations and the last 10 years were used to run a genomic selection scheme with varying levels of collaboration between the local and the mainstream breeding program in the different scenarios. The maximum percentage of breeding bulls selected for breeding to the cows in the local breeding program that could originate from the RDC breeding program differed between scenarios, and could be either 0, 20, 50 or 100%. Results show that the maximum rate of genetic gain in the local breeds was reached in the scenarios where maximum 20, 50 or 100% of the breeding bulls could originate from the RDC breeding program. The highest rate of inbreeding was found in the scenario where no RDC bulls were selected in the local breeding programs. However, even with very restricted selection, the breed proportion of the local breeds dropped significantly after ten years of genomic selection. To really conserve a local breed such as RDN or LIR, a different selection strategy is needed.

Short- and long-term consequences of collaboration between Northern European Red dairy and dual-purpose cattle.

In Northern European countries, a great variety of Red cattle populations exists which can be broadly categorized in two groups: specialized dairy and dual-purpose breeds. Collaboration between these breeds (i.e. the exchange of sires across breeds) can be beneficial but is limited so far. The aim of this study was to demonstrate and evaluate consequences of collaboration between Red breeds using stochastic simulations. Two breeding lines (dairy type and dual purpose) were simulated. As a special aspect of this study, differences in genetic levels of breeding traits (milk production, beef production, mastitis resistance, fertility, feed efficiency) have been taken into account. Various scenarios were investigated where across-breed selection was either restricted or allowed and with different correlations between breeding goals in the two lines. The results of this study were influenced by the different genetic levels in breeding traits only in the first years of simulation. In the long run, the breed differences did not affect the degree of collaboration between lines. When the correlation between breeding goals was close to unity, the selection of external bulls was highly beneficial in terms of genetic gain and total monetary gain. Additionally, the lowest rate of inbreeding was found in that case. With decreasing correlations between environments, degree of cooperation between lines rapidly terminated and lines operated individually. In last years of simulation, cooperation was only found when the correlation between breeding goals was close to unity. From a long-term perspective, the exchange of breeding sires across lines also caused negative effects. In the dual-purpose line, deterioration of genetic gain in mastitis resistance and fertility was observed. Additionally, breeding lines genetically converged, which decreased genetic diversity. Collectively, short-term benefits and long-term negative effects have to be reconciled if collaboration between Red breeds in Northern Europe is to be pursued.

Discovering Copy Number Variation in Dual-Purpose XinJiang Brown Cattle.

Copy number variants (CNVs), which are a class of structural variant, can be important in relating genomic variation to phenotype. The primary aims of this study were to discover the common CNV regions (CNVRs) in the dual-purpose XinJiang-Brown cattle population and to detect differences between CNVs inferred using the ARS-UCD 1.2 (ARS) or the UMD 3.1 (UMD) genome assemblies based on the 150K SNP (Single Nucleotide Polymorphisms) Chip. PennCNV and CNVPartition methods were applied to calculate the deviation of the standardized signal intensity of SNPs markers to detect CNV status. Following the discovery of CNVs, we used the R package HandyCNV to generate and visualize CNVRs, compare CNVs and CNVRs between genome assemblies, and identify consensus genes using annotation resources. We identified 38 consensus CNVRs using the ARS assembly with 1.95% whole genome coverage, and 33 consensus CNVRs using the UMD assembly with 1.46% whole genome coverage using PennCNV and CNVPartition. We identified 37 genes that intersected 13 common CNVs (>5% frequency), these included functionally interesting genes such as GBP4 for which an increased copy number has been negatively associated with cattle stature, and the BoLA gene family which has been linked to the immune response and adaption of cattle. The ARS map file of the GGP Bovine 150K Bead Chip maps the genomic position of more SNPs with increased accuracy compared to the UMD map file. Comparison of the CNVRs identified between the two reference assemblies suggests the newly released ARS reference assembly is better for CNV detection. In spite of this, different CNV detection methods can complement each other to generate a larger number of CNVRs than using a single approach and can highlight more genes of interest.

Genetic study of quantitative traits supports the use of Guzerá as dual-purpose cattle

ObjectiveThe aim of this study was to estimate genetic parameters for 305-day cumulative milk yield and components, growth, and reproductive traits in Guzerá cattle.MethodsThe evaluated traits were 305-day first-lactation cumulative yields (kg) of milk (MY305), fat (FY305), protein (PY305), lactose (LY305), and total solids (SY305); age at first calving (AFC) in days; adjusted scrotal perimeter (cm) at the ages of 365 (SP365) and 450 (SP450) days; and adjusted body weight (kg) at the ages of 210 (W210), 365 (W365), and 450 (W450) days. The (co)variance components were estimated using the restricted maximum likelihood method for single-trait, bi-trait and tri-trait analyses. Contemporary groups and additive genetic effects were included in the general mixed model. Maternal genetic and permanent environmental effects were also included for W210.ResultsThe direct heritability estimates ranged from 0.16 (W210) to 0.32 (MY305). The maternal heritability estimate for W210 was 0.03. Genetic correlation estimates among milk production traits and growth traits ranged from 0.92 to 0.99 and from 0.92 to 0.99, respectively. For milk production and growth traits, the genetic correlations ranged from 0.33 to 0.56. The genetic correlations among AFC and all other traits were negative (−0.43 to −0.27). Scrotal perimeter traits and body weights showed genetic correlations ranging from 0.41 to 0.46, and scrotal perimeter and milk production traits showed genetic correlations ranging from 0.11 to 0.30. The phenotypic correlations were similar in direction (same sign) and lower than the corresponding genetic correlations.ConclusionThese results suggest the viability and potential of joint selection for dairy and beef traits in Guzerá cattle, taking into account reproductive traits.

Commercial meat cuts hardness of dual-purpose cattle from Cundinamarca (Colombia) high tropics zone

Este estudio tuvo como objetivo determinar el efecto del biotipo, la edad al sacrificio, la condición sexual y el sistema de alimentación sobre la dureza de cuatro cortes comerciales: Lomo (Longissimus dorsi), Bota (Biceps femoris), Muchacho (Semitendinosus) y Paletero (Infraspinatus), provenientes de 50 bovinos pertenecientes a sistemas de doble propósito del trópico alto en el departamento de Cundinamarca, Colombia. Para la obtención de los valores en este atributo se emplearon los métodos de medición instrumental de fuerza de corte con cuchilla de Warner-Bratzler y la evaluación sensorial, cuya correlación fue del 71%. Esto permitió la elaboración de una escala de dureza en la cual los cortes Lomo y Paletero se ubicaron en la categoría de “suave” (blando) y se comportaron estadísticamente igual en ambos métodos de medición, mientras que los cortes Bota y Muchacho se ubicaron en la categoría de “medio” y tuvieron diferencias estadísticas de acuerdo con la percepción dada por el panel sensorial. Así mismo, los resultados obtenidos mostraron diferencias significativas entre los cortes, destacando al Paletero por su menor valor de dureza y comportamiento similar al Lomo. Efectos significativos sobre la dureza de la carne fueron encontrados para todos los factores a excepción de la edad, lo cual muestra la influencia que tienen estos y su manejo en finca sobre la calidad de la carne.

Estimation of direct and maternal genetic effects and annotation of potential candidate genes for weight and meat quality traits in a genotyped outdoor dual-purpose cattle breed.

With regard to potential applications of genomic selection in small numbered breeds, we evaluated genomic models and focused on potential candidate gene annotations for weight and meat quality traits in the local Rotes Höhenvieh (RHV) breed. Traits included 6,003 birth weights (BWT), 5,719 200 d-weights (200dw), 4,594 365 d-weights (365dw), and 547 records for intramuscular fat content (IMF). A total of 581,304 SNP from 370 genotyped cattle with phenotypic records were included in genomic analyses. Model evaluations focused on single- and multiple-trait models with direct and with direct and maternal genetic effects. Genetic relationship matrices were based on pedigree (A-matrix), SNP markers (G-matrix), or both (H-matrix). Genome-wide association studies (GWASs) were carried out using linear mixed models to identify potential candidate genes for the traits of interest. De-regressed proofs (DRP) for direct and maternal genetic components were used as pseudo-phenotypes in the GWAS. Accuracies of direct breeding values were higher from models based on G or on H compared to A. Highest accuracies (> 0.89) were obtained for IMF with multiple-trait models using the G-matrix. Direct heritabilities with maternal genetic effects ranged from 0.62 to 0.66 for BWT, from 0.45 to 0.55 for 200dW, from 0.40 to 0.44 for 365dW, and from 0.48 to 0.75 for IMF. Maternal heritabilities for BWT, 200dW, and 365dW were in a narrow range from 0.21 to 0.24, 0.24 to 0.27, and 0.21 to 0.25, respectively, and from 0.25 to 0.65 for IMF. Direct genetic correlations among body weight traits were positive and favorable, and very similar from different models but showed a stronger variation with 0.31 (A), −0.13 (G), and 0.45 (H) between BWT and IMF. In gene annotations, we identified 6, 3, 1, and 6 potential candidate genes for direct genetic effect on BWT, 200dW, 365dW, and IMF traits, respectively. Regarding maternal genetic effects, four (SHROOM3, ZNF609, PECAM1, and TEX2) and two (TMEM182 and SEC11A) genes were detected as potential candidate genes for BWT and 365dW, respectively. Potential candidate genes for maternal effect on IMF were GRHL2, FGA, FGB, and CTNNA3. As the most important finding from a practical breeding perspective, a small number of genotyped RHV cattle enabled accurate breeding values for high heritability IMF.

Influence of scattered trees in grazing areas on soil properties in the Piedmont region of the Colombian Amazon.

Trees dispersed in grazing areas are contribute to the sustainability of livestock systems. The interactions between trees and soil are ecological processes that allow the modification of the biology, fertility, and physics of the soil. This study was aimed to assess the influence of dispersed trees in pastures on soil properties in grazing areas for dual-purpose cattle systems in the Piedmont region of the Colombian Amazon. The work was done in grazing areas with scattered trees at the Centro de Investigaciones Amazónicas CIMAZ–Macagual in Florencia—Caquetá—Colombia. We evaluated the effect of five tree species, Andira inermis, Bellucia pentámera, Guarea Guidonia, Psidium guajava and Zygia longifolia, on soil properties (up to 30 cm soil depth) under and outside the influence of the crown. Under the tree crown, three points were systematically taken in different cardinal positions. This was done at a distance corresponding to half the radius of the tree crown. The sampling points in the open pasture area (out of crown) were made in the same way, but at 15 m from the crown border. The ANOVA showed significant interaction (P < 0.0001) between tree species and location for macrofauna abundance up to 30 cm soil depth. For this reason, we performed the comparison between locations for each tree species. Chemical soil variables up to 10 cm soil depth only showed interaction of tree species-location for exchangeable potassium (P = 0.0004). Soil physical soil characteristics up to 30 cm soil depth only showed interaction of tree species-location at 20 cm soil depth (P = 0.0003). The principal component analysis for soil properties explained 61.1% of the total variability of the data with the two first axes. Using Monte Carlo test, we found crown effect for all species. Trees help to control exchangeable mineral elements that can affect the soil, potentiate basic cations such as magnesium and potassium, increase the abundance of soil macrofauna; but some trees with high ground level of shade in grazing areas could increase soil compaction due to the greater concentration of cattle in these areas.

Carbon footprint in Latin American dairy systems.

The study reviewed carbon footprint (CF) analyses for milk production in Latin America from cradle to farm gate. The objective was to estimate (1) the effect of feeding management (zero-grazing, semi-confinement, and pasture), (2) cattle system (specialized dairy vs. dual-purpose), and (3) region (tropical vs. temperate) on milk production (kg/cow/day) and CF (kg CO2eq/kg fat and protein corrected milk (FPCM)). A systematic literature review was conducted, and for the final analysis, a total of 32 individual CF (from 11 studies) were used. Studies included in the final analysis allowed to calculate CF per kg FPCM, included upstream emissions calculations, and used the IPCC's tier 2 approach for enteric methane emissions. The range of the CF observed in the region was from 1.54 to 3.57kg CO2eq/kg FPCM. Feeding management had a significant effect on milk production, but not on CF. Zero-grazing compared with pasture systems had a 140% greater milk production (20.1 vs. 8.4kg milk/cow/day), but numerically greater CF for pasture systems (2.6 vs. 1.7kg CO2eq/kg FPCM). Compared with specialized dairy cattle, dual-purpose cattle produced less milk (P < 0.001) and higher CF (P < 0.05). Compared with temperate regions, tropical region systems produced less milk and higher CF. In conclusion, in Latin America, the cattle system and region have a significant impact on CF, whereas the feeding management (zero-grazing, semi-confinement, and pasture) does not impact the CF of milk produced.

Reverse Genetic Screen for Deleterious Recessive Variants in the Local Simmental Cattle Population of Switzerland.

Simple SummaryToday’s Swiss Simmental represents a local dual-purpose breed of cattle. Within closed populations, deleterious variants can reach problematic frequencies, explaining substantial proportions of inbreeding depression. Depletions in homozygous genotypes for certain haplotypes among large cohorts of animals genotyped for the purpose of genomic selection is a widely used approach to pinpoint undesired recessive alleles. In the course of a reverse genetic screen, we aimed to identify single recessive Mendelian variants that potentially affect fertility and rearing success without any phenotypic information available. We detected eleven genome regions showing obvious depletion of homozygosity based on genome-wide SNP data. Furthermore, after performing whole-genome sequencing of selected animals, we propose three candidate causative variants affecting different genes with possibly detrimental effects for embryonic development. The established haplotypes, as well as the identified protein-changing variants, can be directly implemented into breeding practice to avoid the risk of mating carriers and thereby increase breeding success.We herein report the result of a large-scale reverse genetic screen in the Swiss Simmental population, a local dual-purpose cattle breed. We aimed to detect possible recessively inherited variants affecting protein-coding genes, as such deleterious variants can impair fertility and rearing success significantly. We used 115,000 phased SNP data of almost 10 thousand cattle with pedigree data. This revealed evidence for 11 genomic regions of 1.17 Mb on average, with haplotypes (SH1 to SH11) showing a significant depletion in homozygosity and an allele frequency between 3.2 and 10.6%. For the proposed haplotypes, it was unfortunately not possible to evaluate associations with fertility traits as no corresponding data were available. For each haplotype region, possible candidate genes were listed based on their known function in development and disease. Subsequent mining of single-nucleotide variants and short indels in the genomes of 23 sequenced haplotype carriers allowed us to identify three perfectly linked candidate causative protein-changing variants: a SH5-related DIS3:p.Ile678fs loss-of-function variant, a SH8-related CYP2B6:p.Ile313Asn missense variant, and a SH9-related NUBPL:p.Ser143Tyr missense variant. None of these variants occurred in homozygous state in any of more than 5200 sequenced cattle of various breeds. Selection against these alleles in order to reduce reproductive failure and animal loss is recommended.

PSXIV-26 Selection footprints in Russian red cattle identified by linkage disequilibrium blocks based on SNP data

Abstract Among the variety of cattle breeds in Russia, the Russian red dual-purpose cattle breeds have great importance because of their ability to produce high milk yields as well as to provide excellent milk quality. The low census size of the Russian red cattle breeds requires development of programs for conservation of their biodiversity. Our study aimed to investigate selection footprints in Russian red cattle breeds, using high values of linkage disequilibrium (LD) in SNP haplotype blocks as indicators. For finding such LD blocks, we used the genotypes (≈35K SNPs) of Red Gorbatov (RGB, n = 26), Bestuzhev (BST,n = 27), and Suksun (SKS,n = 17) breeds, as well as Red Holstein (RH,n = 16) as an outgroup. Quality control and LD calculations for different distances were performed in Plink 1.90. Top 0.01% SNP pairs by LD value (0.9≤r2&amp;lt; 1.0) were selected for further analysis. The effective population size derived from LD patterns was estimated using SNeP tool. Comparison of LD values for 70 kb interval between breeds and chromosomes by MANOVA pairwise testing significantly distinguished RH/RGB and BST/SKS breeds (P &amp;lt; 0.05-0.001). LD values among chromosomes were 0.195–0.287 for RH, 0.194–0.272 for RGB, 0.172–0.237 for BST, and 0.157–0.217 for SKS. The SKS and BST breeds had higher Ne values (84 and 113, respectively) compared to RH (63) and RGB (79). Selection footprints by LD blocks in Russian red cattle genome covered several relevant genes on BTA1 (EPHA6,DGKG), BTA2 (LRP1B,THSD7B,STAT1), BTA5 (CPM,BAIAP2L2), BTA9 (TRDN,UTRN), BTA10 (KCNN2,CAPN3), BTA11 (SH3RF3,RABGAP1,RALGPS1), BTA14 (ZNF16,ARHGAP39,TOX,DGAT1), and BTA19 (MYH10), BTA22 (FHIT). Detected genes were found to be responsible for milk fat and protein contents, fatty acid composition, somatic cells score, fertility, feet and legs, and udder conformation traits. Our results can be useful for developing the breeding and conservation programs of the Russian red cattle genetic resources. The study was funded by RFBR within project No. 20-516-00020

Reproductive management strategies to reduce postpartum anestrus in dual-purpose cattle

Objective: To share technical aspects and recommendations to improve the reproductive and productive efficiency of dual-purpose cattle. Design/Methodology/Approach: A review of scientific articles published in journals was carried out to show the importance of some factors that limit reproduction, as well as to identify management strategies to increase the reproductive potential in dual-purpose cows. Results: The duration of postpartum anestrus is reduced by weaning calves at a few days or weeks of age, restricting suckling to short periods of the day, delaying suckling, and exposing cows to a bull during postpartum. On average, the combined effect of delayed suckling and exposure of cows to a bull reduces postpartum anestrus to less than 50 d and the calving-conception interval to 84 days. Milk production and calf weight gain also are improved without affecting postpartum weight changes in cows. Study Limitations/Implications: Extensive management of dual-purpose cattle reduces the intensive use of some reproductive biotechnologies commonly applied in other animal production systems. Findings/Conclusions: Improvement in the reproductive efficiency of dual-purpose cattle can be achieved by reducing the postpartum anestrus by using reproductive management strategies and minor modifications to common management practices.