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Simple Summary: Bovine tuberculosis is a disease that affects cattle and other animal species worldwide and represents a risk to public health. Even though there is a vaccine that has been used to control tuberculosis in humans for almost 100 years, up to now, it has not been used in animals. The reason is that vaccination interferes with the tuberculin test, the current test to diagnose tuberculosis in the field, and shows an inconsistent efficacy in animals. Recent studies report that prime vaccinating with BCG and boosting with proteins vaccinations perform better. In addition, there are reports that some polymers increase the immune response against various infectious diseases; therefore, testing a vaccine formula with polymers sounds like a wise thing to do. In this study, we showed that priming with BCG and boosting with a culture filtrate protein, alone or in combination with a polymer, the number of animals with lesions, the number of lesions per animal, and the size of the lesions in vaccinated animals, compared with those not vaccinated or those vaccinated with BCG alone, are significantly reduced. Our results mean that a vaccination used as a complement of actual tuberculosis control programs in animal populations can be useful to reduce tuberculosis dissemination. Attempts to improve the immune response and efficacy of vaccines against tuberculosis in cattle, goats, and other animal species have been the focus of research in this field during the last two decades. Improving the vaccine efficacy is essential prior to running long-lasting and expensive field trials. Studies have shown that vaccine protocols utilizing boosting with proteins improve the vaccine efficacy. The use of polymers such as chitosan and PolyLactic-co-Glycolic Acid (PLGA) improves the immune response against different diseases by improving the interaction of antigens with the cellular immune system and modulating the host immune response. This study shows that the prime BCG vaccination, boosted with a culture filtrate protein (CFP), alone or in combination with chitosan and PolyLactic-co-Glycolic Acid (PLGA), have the potential to reduce tuberculosis (TB) dissemination by reducing the number of animals with lesions, the number of lesions per animal, and the size of the lesions in vaccinated animals, compared with those not vaccinated or those vaccinated with BCG alone. The vaccinated groups showed significantly higher Interferon-γ levels in the blood compared to the control, nonvaccinated group after vaccination, after boosting, and after the challenge with the wild-type Mycobacterium bovis strain. [ABSTRACT FROM AUTHOR]

The objective was to evaluate some morphological characteristics of backyard chickens (n=255) coming from 65 rural production units located in 52 municipalities of 18 States of the Mexican Republic. The statistical model included sex, state, and municipality within state. Sex affected all the response variables (P<0.0001), except massiveness index (P=0.3369). State affected all the response variables (P<0.0001) and municipality was only important for wingspan (P<0.0001), body weight (P<0.0271) and stockiness index (P<0.0267). Male chickens had greater (P<0.0001) body length (4.85 cm more), wingspan (5.66 cm more), breast circumference (2.94 cm more), shank length (1.73 cm more), body weight (0.65 kg more) and massiveness index (0.99 percentage points) than female chickens. Body weight increased 126 g (P<0.01) in males and 61 g in females (P<0.01) for each centimeter increment in breast circumference. Body weight showed to be moderately correlated (P<0.01) with body length (r= 0.65), wing span (r= 0.49), length of the shank (r= 0.67) and highly correlated with breast circumference (r= 0.76 in males). The Mexican backyard chicken presented significant morphological differences between males and females for traits studied, except for massiveness index. [ABSTRACT FROM AUTHOR]

Simple Summary: Giardia duodenalis is a flagellated protozoan that has been reported worldwide. Its resistance to adverse climates and its wide host range makes this parasite a serious problem specifically in developing countries where personal hygiene practices are inadequate. The magnitude of the risk of transmission from cats to humans is not well known; to date, in Mexico, there has not been a single study of the presence of G. duodenalis in cats. Therefore, the objective of this work is to determine the frequency and importance of the cat as a potential zoonotic reservoir of Giardia. Sampling of feces was performed in private clinics and an animal control unit. A direct microscopy diagnosis was carried out, and once positive results were obtained, PCR and RFLP were performed in order to obtain assemblages. The results obtained in the present study, in terms of the genetic characterization, showed only assemblage A, which indicates that the cat is an important source of transmission to humans, with consequences for public health. Giardia is a protozoan that affects humans as well as a wide range of domestic species. It is distributed worldwide, and the highest frequency is seen in developing countries. Due to the potential for domestic cats to be carriers of this parasite and subsequently transmit the infection to humans, it is important to know the risk of transmission. For this reason, the objective of this study was to determine the frequency of this parasite in the cat population of the city of Santiago de Queretaro, Mexico, and identify the assemblages present to determine the role this host plays in public health, this being the first study of its type to be performed in the country. This was a cross-sectional study during which 200 fecal samples were collected from cats of both sexes and varying ages and strata of origin. The samples were analyzed by microscopy following the flotation technique, having obtained a general frequency of 25%. Giardia cysts were found at higher frequency in pasty stools. The assemblages found were zoonotic, specifically assemblage A, which suggests that the cat poses an important risk for the dissemination of the parasite to humans, making it an important public health problem. [ABSTRACT FROM AUTHOR]

Simple Summary: Bovine tuberculosis is an infectious disease of cattle caused by Mycobacterium bovis characterized by the formation of tubercles in any organ or tissue. Bovine tuberculosis represents a significant veterinary and public health problem in many parts of the world. It is zoonotic, transmitted to humans through consumption of infected milk and other cattle products. Although many factors influence infection and progression of the disease, there must be an important host genetic component that explains why some animals get sick and others remain healty. We present evidence of genetic variants associated with resistance to tuberculosis in Mexican Holstein dairy cattle using a case-control approach with a selective DNA pooling. Here, we identified novel quantitative trait loci regions harboring genes involved in Mycobacterium spp. immune response. This is a first screening about resistance to tuberculosis infection on Mexican Holstein cattle based on a dense single nucleotide polymorphism chip. The identified genes belong to both, the already known, and the undisclosed quantitative trait loci regions. Bovine tuberculosis (bTB) is a disease of cattle that represents a risk to public health and causes severe economic losses to the livestock industry. Recently, genetic studies, like genome-wide association studies (GWAS) have greatly improved the investigation of complex diseases identifying thousands of disease-associated genomic variants. Here, we present evidence of genetic variants associated with resistance to TB in Mexican dairy cattle using a case-control approach with a selective DNA pooling experimental design. A total of 154 QTLRs (quantitative trait loci regions) at 10% PFP (proportion of false positives), 42 at 5% PFP and 5 at 1% PFP have been identified, which harbored 172 annotated genes. On BTA13, five new QTLRs were identified in the MACROD2 and KIF16B genes, supporting their involvement in resistance to bTB. Six QTLRs harbor seven annotated genes that have been previously reported as involved in immune response against Mycobacterium spp: BTA (Bos taurus autosome) 1 (CD80), BTA3 (CTSS), BTA 3 (FCGR1A), BTA 23 (HFE), BTA 25 (IL21R), and BTA 29 (ANO9 and SIGIRR). We identified novel QTLRs harboring genes involved in Mycobacterium spp. immune response. This is a first screening for resistance to TB infection on Mexican dairy cattle based on a dense SNP (Single Nucleotide Polymorphism) chip. [ABSTRACT FROM AUTHOR]

Since their introduction to Mexico goats have undergone a long process of adaptation and selection, resulting in highly rustic local animals. However, importation of improved breeds has led to the extinction of some regional breeds. For example, the Criolla Negra goat breed is known for its rusticity and high milk quality, but is in decline. A genetic characterization was done of a Criolla Negra population. Hair samples were collected in three goat herds located in different municipalities of the state of Querétaro, Mexico: Cadereyta de Montes (n= 7); El Marqués (n= 11); and San Juan del Río (n= 27). Thirty microsatellites were used to quantify the number of alleles per marker (NA), median number of alleles (MNA), number of effective alleles (NEA), observed heterozygosis (Ho), expected heterozygosis (He), polymorphic data content (PDC), the fixation index (FIS) and Hardy Weinberg equilibrium (HWE). The Criolla Negra population was compared to thirteen breeds forming part of the BioGoat project. Genetic diversity was found to be high in this population. A total of 243 alleles were identified with an MNA of 8.1 alleles per marker. The markers were informative (PDC= 0.06) for polymorphism. The He (0.71) and Ho (0.62) values indicate a slight imbalance in the population. Reynolds genetic distance results showed the Criolla Negra breed to be genetically furthest from the Anglonubia breed and nearest the Murciano-Granadina breed. The studied Criolla Negra goat population exhibits a breed structure well differentiated from the other breeds in the analysis. [ABSTRACT FROM AUTHOR]

Simple Summary: The need to characterize and document local animal populations has gradually gained global importance. This is because these populations represent a genetic pool, and before developing strategies for their conservation, they need to be evaluated. The Black Creole goat, which is distributed mainly in the central region of Mexico, represents one of the first Creole populations, derived from goat cattle introduced 500 years ago by Spanish colonizers. However, morphological and racial standards have not been established for this population, even though the quality of their milk and the social importance they represent in semi-desert areas are known. In the present study, the morphostructure of the Black Creole goat was evaluated using morphometric variables that describe the body conformation of the animals. The results showed a homogeneous population and confirmed the zootechnical purpose of the animals. These results represent the first morphological study carried out on the Black Creole goat and could be the basis for establishing its racial standard. In order to evaluate the morphostructural variability of the Black Creole goat (BCG), the present study was carried out in a population of 226 animals from eight localities and 14 morphometric variables were taken. Descriptive statistics for the variables were obtained and 10 of these presented variation coefficients of less than 10%. The degree of harmony in the morphology of the population was determined by the number of positive correlations with significant differences (p < 0.05), including a correlation test using Spearman's method. In order to reduce the matrix of variables, a principal components analysis was performed, and it was evaluated based on Kaiser's criteria (eigenvalue > 1). Finally, a hierarchical analysis of conglomerates using Ward's method was performed using the Euclidean distance to evaluate the distances among localities. Morphometric variables were also included to visualize the relationship among the localities and their average per variable. The results showed that the animals evaluated presented a certain degree of homogeneity and maintained a highly harmonic model. The BCG population showed a high aptitude for milk production, which confirmed the zootechnical purpose of the breed. The BCG populations evaluated maintain similar morphostructural profiles specific to them that can distinguish this population from other animal breeds. [ABSTRACT FROM AUTHOR]

A medida que disminuyen los costos de la genotipificación, la demanda de ésta crece entre los ganaderos. En la mayoría de los hatos pecuarios es importante controlar el aumento del coeficiente de consanguinidad. Si bien esto es un motivo considerable para llevar a cabo la genotipificación, con frecuencia los productores desconocen los demás beneficios que puede traerles. El propósito de este estudio fue demostrar que es posible utilizar los chips SNP como una herramienta eficaz para el manejo de los hatos utilizando una población de ganado italiano Holstein-Friesian. Después de filtrar, se retuvo un total de 44 animales y 27,365 SNP para analizarlos. Los análisis de componentes principales (ACP) lograron identificar al progenitor y el efecto del origen del mismo en los análisis de componentes (ACP), y a la vez determinar que los sementales no influyen en los valores individuales del índice de selección genética. Los coeficientes de consanguinidad calculados a partir de los genotipos (FIS) permitieron tener un atisbo de la heterocigosidad del hato y determinar que la variabilidad genética se está manteniendo exitosamente. Por otra parte, se dedujeron los coeficientes de consanguinidad a nivel genético con base en los tramos de homocigosidad (FROH) y se los comparó con los índices de consanguinidad basados en el pedigrí (FPED). Además, se identificaron 1,950 tramos de homocigosidad (ROH) con una longitud promedio de ROH de 4.66 Mb. Se caracterizaron los genes y QTL dentro de las regiones genéticas más comúnmente asociadas (primer 1 % y primer 5 % de los SNP). Estos resultados indican que la genotipificación de hatos pequeños, aunque a una densidad baja, facilita una mejor comprensión de la variabilidad genética dentro del hato y así, permiten a los productores gestionar su ganado desde una perspectiva genética. [ABSTRACT FROM AUTHOR]

The objectives of this research were to assess the genetic diversity, population structure, linkage disequilibrium and perform a genome-wide association study (GWAS) to search for single nucleotide polymorphisms (SNPs) that associate with the resistance of Pacific white shrimp (Litopenaeus vannamei) to White Spot Syndrome Virus (WSSV). The line here analyzed was formerly founded with animals originated from different origins (Ecuador, Panama, and United States of America), with a history of resistance to WSSV and they have undergone a selection process, currently reaching up to F6 generation. In a controlled challenge to WSSV, this line showed a binary survival (39.0% ± 1.1%) and time to death (109.7 ± 0.9 h post-infection) (n = 1944). The population was genotyped using a commercially available 50 K SNP chip and ∼32 K SNPs remained after quality control of genotypes. Population structure, extent and decay of linkage disequilibrium (LD), and genetic variability in the population were evaluated. The principal component analysis (PCA) did not show apparent genetic stratification in the population. The LD decay estimated, revealed a rapid decrease in r 2 as the physical distance between markers increased. The most significant decrease was observed in the first 30Kb of distance, suggesting the need to use a higher density of informative markers to meet the requirement of a genome-wide association study in L. vannamei. The observed and expected heterozygosities were both = 0.38, which indicates that the population presents acceptable genetic variability for WSSV resistance. Two SNPs were significantly associated to WSSV resistance at a genome-wide level, which in turn together explained 0.17% of the genetic variance for the trait. One identified SNP surpassing the genome-wide significance threshold (chromosome 1 at 51207389 bp) is located near potential candidate genes, such as Arylsulfatase B-like (ARSB), and D-beta-hydroxybutyrate dehydrogenase mitochondrial-like (βhyD); which was linked to the humoral immune response to WSSV, in addition to the Putative mediator of RNA polymerase II transcription subunit 26 (PMed26); which are associated with the hepatopancreas immune response against infection of WSSV and acute hepatopancreatic necrosis disease (AHPND). Our results indicate a polygenic architecture for WSSV resistance in L. vannamei , suggesting that incorporating genome-wide SNP information, through genomic selection, might be the most appropriate approach to accelerate the genetic progress for this trait. • The use of medium-density chips allows us to know the variability and genetic structure of phenotypes in L. vannamei. • SNPs related to genes associated with the immune response of L. vannamei to WSSV explain little of the phenotypic variance. • A polygenic architecture for binary survival and time to death is suggested for WSSV resistance in L. vannamei. • The use of SNP information through genomic selection could be a suitable approach to improve WSSV resistance in L. vannamei. [ABSTRACT FROM AUTHOR]

Data from 241 interviews collected in 2013 was analyzed to characterize populations of pigs (Mexican Hairless Pig (MH), Cuino Pig (CU) and Crossbred Pig (UD)). Variables were body weight (BW), head length (HL), body length (BL), thoracic perimeter (CG), height at withers (HW), croup width (RW), number of nipples (TC), dense or sparse hair (HD), presence or absence of tusks (TU), short or long snout (ST), upright or floppy ears (ER), calm or restless temperament (TM), proportionality index (PI), body index (BI) and relative weight index (RWI). Analyses were carried out with GLM and GENMOD of SAS. Models included state and population. Population was significant (P<0.05) for BW, BL, CG, HW, RW, TU, TM, PI, BI and RWI. Coefficients of variation (VC) showed the minor and major values for BW (18.8 %) and CG (27.8 %). VC were 13.0, 14.6 and 45.8 % for PI, BI and RWI. Least squares means for MH, CU and UD were: 48.06±6.17a, 35.93±3.04b and 61.11±7.42a kg (BW); 77.81±3.65ab, 69.56±2.02a and 88.52±4.93b cm (BL); 80.55±3.98ab, 71.72±2.20a and 93.23±5.37b cm (CG); 56.88±2.45ab, 51.26±1.36a and 60.32±3.31b cm (HW); 57±4a, 71±19b and 62±34a % (HD); 68±31ab, 70±14a and 61±27b% (TU); 65±30a, 56±12b and 62±3a% (TM). The MH and UD populations were similar in morphometry and different from the CU population. The CU population showed lower weight, smaller size and calmer temperament. The characterization of these populations is important for designing strategies for their conservation and efficient use. [ABSTRACT FROM AUTHOR]

The objective was to evaluate some morphological characteristics of backyard turkeys (n=248) coming from 126 rural production units located in 75 municipalities of 24 States of the Mexican Republic. The statistical model included sex, state, and municipality within state. The three explanatory variables affected all the response variables (P<0.01), except municipality, which did not affect breast circumference (P>0.05). Male turkeys had greater (P<0.001) body length (10.7 cm more), wingspan (11.4 cm more), breast circumference (13.8 cm more), shank length (2.5 cm more), body weight (2.5 kg more), stockiness (9.0 percentage units more) and massiveness (2.8 percentage units more) than female turkeys. Body weight showed to be highly correlated phenotypically (P<0.01) with breast circumference in both males (r=0.74) and females (r=0.71). Body length was lowly correlated with shank length (r=0.25; P<0.01) in males, but it was not correlated with shank length in females (r=0.05; P>0.05). Body weight increased 143 g in males (P<0.01) and 113 g in females (P<0.01) for each centimeter increment in breast circumference. The predominant colors in the plumage, skin and tarsus were black, white and brown, respectively. The Mexican backyard turkey presented significant sexual dimorphism and strong phenotypic correlation between breast circumference and body weight. [ABSTRACT FROM AUTHOR]