Economic and financial viability of a pig farm in central semi-tropical Mexico: 2022-2026 prospective.

To estimate the economic and financial viability of a pig farm in central sub-tropical Mexico within a 5-year planning horizon, a Monte Carlo simulation model was utilized. Net returns were projected using simulated values for the distribution of input and product processes, establishing 2021 as base scenario. A stochastic modelling approach was employed to determine the economic and financial outlook. The findings reveal a panorama of economic and financial viability. Net income increased by 555%, return on assets rose from 3.36% in 2022 to 11.34% in 2026, and the probability of decapitalization dropped from 58% to 13%, respectively in the aforesaid periods. Similarly, the probability of obtaining negative net income decreased from 40% in 2022 to 18% in 2026. The technological, productive, and economic management of the production unit allowed for a favorable scenario within the planning horizon. There is a growing interest in predicting the economic sectors worth investing in and supporting, considering their economic and development performance. This research offers both methodological and scientific evidence to demonstrate the feasibility of establishing a planning schedule and validating the suitability of the pork sector for public investment and support.

Expression and localization of vascular endothelial growth factor and its receptors in the pig uterus during peri-implantation and determination of the in vitro effect of the angiogenesis inhibitor SU5416 on VEGF system expression.

The aim of this work was to determine endometrial mRNA expression and uterine protein localization of vascular endothelial growth factor (VEGF) and its receptors VEGFR1 and VEGFR2 during the estrous cycle and peri-implantation period in sows. Uterine tissues were collected from pregnant sows on days 12, 14, 16, and 18 after artificial insemination and from non-pregnant animals on days 2 and 12 of the estrous cycle (day 0 = day of estrus). Using immunohistochemistry, a positive signal for VEGF and its receptor VEGFR2 was found in uterine luminal epithelial cells, endometrial glands, stroma, blood vessels, and myometrium. A VEGFR1 signal was only found in endometrial and myometrial blood vessels and stroma. By day 18 of gestation, the mRNA expression levels of VEGF, VEGFR1, and VEGFR2 were higher than those observed on days 2 and 12 of the estrous cycle and on days 12, 14, and 16 of gestation. Then, a primary culture of sow endometrial epithelial cells was established to define the potential of the selective inhibition of VEGFR2 after treatment with inhibitor SU5416 and determine its effects on the expression pattern of the VEGF system. The endometrial epithelial cells treated with SU5416 showed a dose-dependent decrease in VEGFR1 and VEGFR2 mRNA expression. The present study provides additional evidence on the importance of the VEGF system during peri-implantation, as well as on the specific inhibitory activity of SU5416 in epithelial cells, which, as demonstrated, express the protein and mRNA of VEGF and its receptors VEGFR1 and VEGFR2.

Boar semen cryopreserved with trehalose-containing liposomes: disaccharide determination and rheological behaviour.

This study aimed to detect intracellular trehalose in boar sperm that were cryopreserved with liposomes and conduct an analysis of its effects on some characteristics of thawed sperm, including rheological properties. First, soybean lecithin cholesterol-based liposomes were produced and characterized in the presence of 300 mM trehalose. Next, semen samples were frozen in two freezing media: a control medium with 300 mM trehalose and an experimental medium supplemented with 300 mM trehalose and 10% liposomes, both of which were thawed and then studied to ascertain their integrity, motility, rheological response, and trehalose quantities by testing two methods of spermatic lysis via high-performance liquid chromatography with an evaporative light-scattering detector (HPLC-ELSD). The results found spherical liposomes measuring 357 nm that were relatively stable in an aqueous medium and had an entrapment efficiency of 73%. An analysis of the cryopreserved ejaculates showed that their viability and motility did not significantly differ between groups (P > 0.05). The viscous response of the samples was influenced by the extracellular medium rather than by the freezing-thawing process, which resulted in a loss of interaction between the cells and cryoprotectants. Finally, intracellular trehalose levels were determined using HPLC-ELSD, with no differences observed (P > 0.05) when comparing both sperm lysis methods. The use of liposomes with trehalose appears to be a promising option for boar semen cryopreservation, with a marked effect on rheological properties. The proposed HPLC-ELSD method was effective for measuring trehalose in cryopreserved cell samples.

Postnatal testicular development in Vietnamese pot-bellied pigs.

The Vietnamese pot-bellied pig is a breed with high investigation potential. However, at the reproductive level, its testicular characteristics are still unknown, as well as the different stages of its development. Therefore, the objective of this work is to describe the postnatal testicular development of Vietnamese pot-bellied pigs. In this study, we used pigs grouped into the neonatal stage, animals at zero weeks; prepubertal stage, animals at three and eight weeks; pubertal stage, animals at twelve and sixteen weeks; and postpubertal stage animals at twenty, twenty-four, twenty-eight and thirty-two weeks of age. The neonatal stage is characterized by gonocytes at different migration phases. In the prepubertal stage, gonocytes were differentiated into spermatogonia at 3 weeks of age, and the first spermatocytes were observed at 7 weeks of age. Puberty was determined to start at 12 weeks because seminiferous tubules are found with complete spermatogenesis and the highest peaks in positive cell counting of androgen receptors (AR) and proliferating cell nuclear antigen (PCNA) factor that later decreased and further stabilized in the following weeks. In the postpubertal stage, an increase in seminiferous tubule areas was observed. The number of apoptotic cells ranged from low to null at all ages. Testosterone (T) and gonadotropin levels had two important peaks at 3 and 24 weeks. The seminiferous epithelium cycle was found to have 11 stages according to acrosome development. These characteristics of Vietnamese pot-bellied pig testes, which are different from rat testes and more similar to human testicles, make them a viable model to study human male reproductive biology. The postnatal testicular development of pot-bellied pigs is different from the postnatal testicular development of other breeds. Therefore, due to this difference in size and easy manipulation, the Vietnamese pig is an alternative for investigation compared to other pig breeds.

Molecular Detection and Characterization of Porcine Epidemic Diarrhea Virus and Porcine Aichivirus C Coinfection in México.

Swine enteric viral infections are responsible for substantial economic losses in the pork industry worldwide. Porcine epidemic diarrhea (PEDV) is one of the main causative agents of diarrhea in lactating pigs, and reports of PEDV coinfection with other enteric viruses highlight the importance of viral interactions for disease presentation and outcomes. Using next-generation sequencing (NGS) and sequence analyses from samples taken from piglets with acute diarrhea, we explored the possible interactions between PEDV and other less reported pathogens. PEDV coinfection with porcine kobuvirus (PKV) was detected in 36.4% (27/74) of samples. Full genomes from porcine coronavirus and kobuvirus were obtained, as was a partial porcine sapovirus genome (PSaV). The phylogenetic results show the clustering of these strains corresponding to the geographical relationship. To our knowledge, this is the first full genome and isolation report for porcine kobuvirus in México, as well as the first phylogenetic analysis for porcine sapovirus in the country. The NGS approach provides a better perspective of circulating viruses and other pathogens in affected production units.

Serological and molecular study of Hepatitis E virus in pediatric patients in Mexico.

INTRODUCTION AND OBJECTIVES: Cases of viral hepatitis reported in Mexico are typically identified as hepatitis A, B and C. However, unspecified cases are reported annually. Hepatitis E virus (HEV) is an emergent agent that causes a self-limiting infection that can evolve to chronic in immunosuppressed individuals. In Mexico, HEV genotype 2 is considered endemic, though it's the prevalence is not well known. Therefore, the present study was designed to determine the prevalence of HEV among patients at the "Hospital Infantil de Mexico Federico Gomez". MATERIALS AND METHODS: The study included 99 patients, anti-HEV antibody (IgG and IgM) were detected by indirect ELISA and viral genome was identified using RT-PCR technique. Two PCR products of positive cases were sequenced. RESULTS: ELISA results were positive in 3% and 6%, for IgG and IgM respectively, 54.5% prevalence was found by PCR. Low lymphocyte count (p<0.05) and malnutrition (p<0.005) were significant factors for high PCR prevalence and could increase the possibility of infection. Two samples were sequenced and confirmed the presence of HEV genotype 3. CONCLUSIONS: This report reveals the incidence of HEV in pediatric patients in Mexico. Moreover, the identification of HEV genotype 3 in human samples suggests a potential zoonotic risk that requires further research.

Clinical evaluation, serological response and lesions generated by the A/Mexico/La Gloria-3/2009/H1N1 and A/swine/New Jersey/11/1976/H1N1 influenza viruses in colostrated and non-colostrated pigs.

Influenza A viruses cause respiratory disease in piglets, and maternal immunity plays an important role in protecting against Influenza virus infection. Nevertheless, in the presence of high levels of maternal antibodies against influenza, an adequate immune response is not developed. In this study, the effect of maternal antibodies against the swine influenza A/swine/New Jersey/11/1976/H1N1 virus (swH1N1) on clinical presentation, serological response, and lesions produced in colostrated and non-colostrated pigs was evaluated in pigs infected with the human influenza A/Mexico/La Gloria-3/2009/ H1N1 (pH1N1) and swH1N1 viruses. Our results indicated that between 2 and 4 days post-challenge, sneezing and mild nasal discharge were observed in all pigs. Body temperature in pigs from all treatment groups ranged between 39.2 and 39.3 °C. Pigs inoculated with the pH1N1 virus (421 g) exhibited a significantly lower daily weight gain than those inoculated with the swH1N1 virus (524 g). HI antibody titers against the pH1N1 virus were significantly different between colostrated (1.62) and non-colostrated (0.43) pigs. Significant differences in antibody titers were detected between pigs inoculated with the pH1N1 (1.28) or the swH1N1 virus (0.77) (P < 0.05). The highest percentage of pulmonary lesions was observed in non-colostrated/pH1N1 pigs (11.88%) at 6 days post-challenge. Cross reactivity was observed between the pH1N1 and swH1N1 viruses, as the maternal antibodies against the swH1N1 virus successfully neutralized the pH1N1 virus infection.

An Escherichia coli-Expressed Porcine Reproductive and Respiratory Syndrome Virus Chimeric Protein Induces a Specific Immunoglobulin G Response in Immunized Piglets.

Porcine reproductive and respiratory syndrome virus (PRRSV) still poses a threat to the swine industry worldwide. Currently, commercial vaccines against PRRSV, which consist of modified live or inactivated virus, reduce symptoms and viremia in immunized pigs, but efficacy against heterologous strains is variable. This has led to the development of subunit vaccines that contain viral antigens that show the highest variability. In this work, a chimeric protein comprising short amino acid sequences from glycoprotein 3 (GP3), glycoprotein 4 (GP4), glycoprotein 5 (GP5), and M (matrix protein) proteins of PRRSV was designed and expressed in Escherichia coli. This protein, designated as PRRSVchim, was purified by immobilized metal affinity chromatography and evaluated. PRRSVchim was identified by immunoglobulin G (IgG) presence in serum samples from PRRSV-positive pigs. Also, the protein probed to be antigenic in immunized mice and piglets and provided some degree of protection against challenge with a PRRSV field isolate. These results show the potential of PRRSVchim protein for both PRRSV diagnostic and immunoprophylaxis.

Isolation and characterization of porcine epidemic diarrhea virus associated with the 2014 disease outbreak in Mexico: case report.

BACKGROUND: Interest in porcine epidemic diarrhea has grown since the 2013 outbreak in the United States caused major losses, with mortality rates up to 100 % in suckling piglets. In Mexico, an outbreak of porcine epidemic diarrhea, characterized by 100 % mortality in piglets, began in March 2014 in the State of Mexico. METHODS: The aim of this study was to confirm and identify porcine epidemic diarrhea virus (PEDV) in samples from piglets with suggestive clinical signs using virological, histological, and molecular techniques. Necropsy was performed on 13 piglets from two litters with initial and advanced clinical signs. Suggestive lesions of acute infection with PEDV were detected in histological sections of the small and large bowels; specifically, multiple virus particles with visible crown-shaped projections were observed using electron microscopy and negative staining. Viral isolation was performed in Vero cells with trypsin. Infection was monitored by observation of cytopathic effect, and titration was determined by TCID50/ml. The presence of the PEDV in cultures and clinical samples was confirmed by RT-PCR amplification and sequencing of a 651-bp segment of the S glycoprotein gene, as well as a 681-bp matrix protein gene. RESULTS: The nucleotide sequence analysis of the Mexican isolates showed marked homology to viruses that circulated in 2013 in Colorado, USA. CONCLUSIONS: In this paper we confirm the isolation and characterization of PEDV from animals with early and advanced clinical signs.

Factores estresantes en lechones destetados comercialmente / Stress factors in weaned piglet

Hoy en día, las modernas técnicas de producción porcina exigen cada vez más destetes tempranos. Sin embrago, el destete representa una de las etapas más críticas en la vida productiva del cerdo, debido a que durante ella se suman una serie de factores estresantes y cambios fisiológicos. En la presente revisión se analizan los factores más importantes que causan estrés durante esta etapa, como la separación de la cerda, el transporte, el cambio de alimento, el alojamiento en nuevas instalaciones y el agrupamiento con lechones extraños. La interacción de los lechones con estos factores estresantes incrementa el nivel de estrés que representa, per se, la separación de la cerda y el lechón durante el destete, ya que habitualmente originan "retraso en el crecimiento", además de aumento de la susceptibilidad frente a agentes patógenos entéricos causantes de enfermedades. Por ello, los distintos factores que afectan la fisiología, el metabolismo y el comportamiento del lechón deben ser controlados adecuadamente. Se concluye que el conocimiento de la biología de la especie y un entrenamiento adecuado del personal, son necesarios para disminuir los problemas de bienestar del lechón destetado, por lo que, con el fin de evitarlos, se recomiendan algunas prácticas derivadas de los hallazgos presentados.

Nowadays, modern swine production techniques promote early weaning. Weaning constitutes one of the most critical stages in the productive life of swine as it is a phase that entails a whole series of stressful factors and physiological changes. This review examines the most important factors that cause stress during this stage, including: separation from the sow, transport, changes in alimentation, lodging in different installations, and being grouped together with strange piglets. The interaction of young pigs with all these stressor factors exercises a cumulative effect that intensifies the level of stress they experience during separation from the sow during the weaning process itself, an event that frequently results in "delayed growth" accompanied by an increased susceptibility to disease-causing, enteric pathogenic agents. For these reasons, it is important to adequately control the variety of factors that affect the physiology, metabolism and behavior of piglets. The conclusion is that both knowledge of the biology of the species and suitable personnel training are necessary to reduce the problems that arise from these issues related to the welfare of weaned piglets. Finally, this study recommends some practices derived from the findings presented, with a view to improving the welfare of recently weaned piglets.

Glycerol decreases the integrity of the perinuclear theca in boar sperm.

We evaluated the effect of glycerol on the perinuclear theca (PT) of boar sperm. Samples from six ejaculates obtained from three different boars were incubated in the detergent Brij 36-T. Spermatozoa were treated with a glycerol concentration of either 2 or 4%, and incubated for 10 or 30 min; two other samples were treated with protease inhibitors (PI; leupeptin or an inhibitor commercial cocktail), mixed with 4% glycerol, and incubated for 30 min. A third glycerol-free group was used as the control. The samples were processed for electron microscopy evaluation. The PT remained intact in 78% of the control samples while, after addition of glycerol for 30 min, the proportion of spermatozoa with disrupted or absent PT increased (P < 0.05). PT was preserved in PI samples, but PT changes increased (P < 0.05). Differences due to treatment with glycerol (2 or 4%) at 10 or 30 min were not observed. These results show, to our knowledge for the first time, the adverse effect of glycerol on the integrity of the PT.

Estructura etaria, comportamiento productivo y reproductivo de una población de cerdos criados en semiconfinamiento, en una comunidad rural del estado de Morelos, México / Age structure, productive and reproductive behavior of a pig population reared in semi-confinement in a rural community of Morelos state, Mexico

Small-scale family swine production can be seen in thousands of small communities and suburban zones; it is characterized by breeding rural pigs in rustic facilities with basic feed and productive parameters, well below those of technologically advanced farms, with mortality reaching up to 50% of the litter. This type of production involves a large number of producers and has a critical impact on family income. At slaughter, these carcasses have a high probability of being seized because of the presence of cysticercoids (T. solium), losing a high percentage of its economic value; due to absence of slaughterhouses in rural communities, this meat is directed to consumption without health inspection, increasing the risk of transmission of this zoonosis. This paper describes the productive and reproductive characteristics of the backyard production system of pigs in a rural community. Human to pig ratio was 3:1. During the year, 308 piglets were born in 43 litters, 51.7% males and 48.3% females, with an average weight of 40.47 kg at 6 months and 65.30 kg at 10 months. They were slaughtered at 7.3 months on average. The highest death rate was found between 0 and 1 month of age. In many rural communities of Mexico pigs are fed with waste generated in homes, helping maintain the communities clean, as well as with the excreta of other species that usually roam freely, situation that can promote dissemination of parasitic diseases.

La porcicultura familiar es una forma de producción que existe en miles de pequeñas comunidades y zonas conurbadas, caracterizada por la crianza de razas criollas en instalaciones rústicas, con alimentación básica y parámetros productivos inferiores a los de las granjas tecnificadas y una mortalidad hasta de 50% de la camada. Este tipo de producción involucra gran número de productores e impacta críticamente en el ingreso familiar. Al sacrificio, estas canales tienen una alta probabilidad de decomiso por la presencia de cisticercosis (T. solium), por lo que pierden un alto porcentaje de su valor económico; debido a la ausencia de rastros en comunidades rurales, esta carne se destina al consumo directo, sin inspección sanitaria, incrementando los riesgos de transmisión de esta zoonosis. En este trabajo se describen las características productivas y reproductivas del sistema de producción de cerdos en traspatio en una comunidad rural. La razón humano-cerdo fue de 3:1, durante el año se obtuvieron 43 camadas, con 308 lechones nacidos vivos, 51.7% machos y 48.3% hembras, con un peso promedio de 40.47 kg a los 6 meses y 65.30 kg a los 10 meses, siendo sacrificados a los 7.3 meses en promedio, los animales que tienen entre 0 y 1 mes de edad presentan la tasa más alta de mortalidad sin que sean sacrificados. En muchas comunidades rurales de México, se alimentan con desperdicios que se generan en las casas, así como las excretas de otras especies que por lo regular deambulan libremente, situación que puede generar enfermedades parasitarias.

Effects of sildenafil on the fetal growth of guinea pigs and their ability to survive induced intrapartum asphyxia.

OBJECTIVE: Our goal was to determine whether sildenafil increased fetal weight and favored fetal tolerance to induced asphyxia at birth in guinea pigs. STUDY DESIGN: Twenty guinea pigs were randomly allocated to placebo (n = 10) or sildenafil 50 microg/kg (n = 5) or 500 microg/kg (n = 5), starting from day 35 of gestation to delivery. Fetuses were delivered by cesarean section. Fetal asphyxia was induced by clamping the umbilical cord at birth for 5 minutes. RESULTS: Sildenafil protected the pups against induced asphyxia at birth in a dose-dependent manner (eg, partial pressure (tension) of carbon dioxide levels were 75.9 +/- 19.3, 66.9 +/- 18.8, and 54.8 +/- 13.0 in the control and low- and high-dose sildenafil groups, respectively). The high-dose sildenafil group of piglets gained 1.5 times more body weight. CONCLUSION: In guinea pigs, low doses of sildenafil administered from day 35 to the end of gestation favored fetal tolerability to induced intrapartum asphyxia. High doses of sildenafil increased fetal weight.

Efecto de la pérdida de grasa dorsal y peso corporal sobre el rendimiento reproductivo de cerdas primíparas lactantes alimentadas con tres diferentes tipos de dietas / Effect of loss of backfat and body weight on the reproductive performance of primiparous lactating sows fed with three different diets

Se evaluaron 90 cerdas híbridas primíparas de traspatio, que se clasificaron de acuerdo al tipo de dieta en 3 grupos: G1, escamocha (residuos alimenticios de consumo humano); G2, escamocha y concentrado y/o granos, y G3, alimento balanceado. La grasa dorsal se registró a la altura de la décima vértebra torácica mediante ultrasonido. Para evaluar el efecto de las reservas corporales sobre 10 indicadores productivos se utilizó la prueba exacta de Fisher; con una significancia de P<0,01. Los resultados señalaron diferencias significativas entre los tres grupos en los indicadores: peso (Kg) de la cerda al parto (X: G1 101,66; G2 111,3; G3 124,1) y al destete (X: G1 94,30; G2 104,5; G3 118,9); grasa dorsal (mm) al parto (X: G1 11,20 G2 12,66; G3 16,2) y al destete (X: G1 9,46; G2 10,70; G3 13,7); intervalo (días) destete estro (X: G1 23,16 G2 20,1; G3 14,5) y destete concepción (X: G1 27,43; G2 23,73; G3 17,16), y peso (g) individual del lechón al nacimiento en el segundo parto (X: G1 891,40; G2 958,5; G3 1054). En todos los grupos las cerdas perdieron en promedio 6 kg y 2 mm de grasa. Estos datos confirman que a medida que la calidad nutritiva de la dieta mejora, decrecen progresivamente los días que las cerdas requieren para entrar en calor una vez que son destetadas. A pesar del bajo peso al destete de las cerdas con alimentación con base en escamocha, éstas entraton en estro y su gestación fue exitosa aunque con un número moderado de lechones nacidos vivos y un pobre peso al nacimiento

Effect of oxytocin treatment in sows on umbilical cord morphology, meconium staining, and neonatal mortality of piglets.

OBJECTIVE: To evaluate the effect of 2 oxytocin products administered to sows at the onset of fetal expulsion on the integrity of umbilical cords, meconium staining, and piglet mortality. ANIMALS: 2099 neonatal pigs. PROCEDURE: 180 parturient sows were randomly assigned to 3 stratified groups of 60 sows each. Two groups of sows were injected IM at the onset of fetal expulsion with 1 of 2 oxytocin commercial products (20, 40, or 50 U for sows weighing 120 to 150 kg, 151 to 250 kg, or > or = 251 kg, respectively). Control sows were treated IM with saline (0.9% NaCI) solution. Farrowing time, expulsion intervals, and numbers of stillborn and liveborn piglets were recorded for each sow. Piglets were evaluated for inspiratory effort, heart rates, and degree of meconium staining of skin (nonstained, and moderately or severely stained). Umbilical cords were classified as normal in appearance, edematous, congested, hemorrhagic, or ruptured. RESULTS: Oxytocin-treated sows had a significant decrease in farrowing time and expulsion intervals and also had a significantly higher number of stillborn piglets per litter, compared with control sows. The number of piglets per litter with ruptured and hemorrhagic umbilical cords was significantly greater in oxytocin-treated sows, compared with control sows. In near-death stillborn piglets, oxytocin treatment significantly decreased inspiratory efforts at birth and increased the rate and severity of meconium staining, compared with saline treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Oxytocin given to sows at the onset of fetal expulsion significantly increases the rate of fetal distress, anoxia, and intrapartum death in piglets.

Efecto de ondas ultrasónicas de 25 a 50 Khz sobre el rendimiento reproductivo y el peso corporal de ratas Wistar / Effect of 22-50 KHz ultrasonic waves on reproductive performance and weight gain in Wistar rats

El presente trabajo se realizó con el propósito de conocer el efecto de las ondas ultrasónicas generadas por un dispositivo diseñado para ahuyentar roedores y disminuir su reproducción. El efecto de este equipo fue estudiado en ratas Wistar mantenidas en condiciones de bioterio. Con ese propósito se formaron dos grupos de ratas Wistar, uno testigo y el otro experimental, en donde se determinó si la acción constante de un dispositivo productor de ondas ultrasónicas, durante 12 semanas, interfiere con la capacidad reproductiva de ratas Wistar, evaluada por el número de días a parto, número de crías nacidas y destetadas. También se determinó la influencia de las ondas ultrasónicas en el crecimiento y desarrollo de las crías, utilizando como indicador la ganancia de peso semanal desde el destete hasta la doceava semana experimental. Los resultados obtenidos indican que las ondas ultrasónicas no afectan el peso corporal, ya que mediante la prueba de mediciones repetidas se comprobó que si bien existe diferencia aritmética, no hay diferencia estadística entre ambos grupos (P>0.05). En lo que respecta a las crías, el grupo tratado obtuvo 20 crías más que el grupo testigo; sin embargo, no existe diferencia estadística entre ambos grupos (P>0.05). La presencia continua de ondas ultrasónicas tampoco interfirió con la ganancia de peso de las crías, en comparación con el grupo testigo (P>0.05). Se concluye que las ondas ultrasónicas generadas por el aparato no afectan el tamaño y curva de crecimiento posterior al destete de la camada. Como consecuencia de lo anterior no parece recomendable utilizar este tipo de aparatos como un método para el control de roedores.

Sincronización del estro en cerdas nulíparas y primíparas / Estrus synchronization in gilts and sows

Con el objeto de evaluar diferentes tratamientos para logar la sincronización del estro se realizaron dos experimentos. En el primer experimento se formaron 3 grupos con 30 animales cada uno (grupo 1, manejo convencional; grupo 2, Altrenogest; grupo 3, macho vasectomizado). En el segundo experimento, se formaron 2 grupos de 30 cerdas cada uno (grupo A, destete convencional; grupo B, Altrenogest). Los resultados fueron los siguientes: En el primer experimento: La edad a ingreso, fertilidad, promedio de lechones nacidos vivos, el número de lechones nacidos muertos, los lechones momificados y el promedio total de lechones nacidos, todos sin signficancia estadística (P>0.05). En cuanto al número de estro detectados y al número de hembras sincronizadas sí se encontró significancia estadística (P<0.05). En el segundo experimento: Los días de lactancia, el promedio de lechones destetados, la fertilidad, el promedio de lechones nacidos vivos, el número de lechones nacidos muertos y el promedio total de lechones nacidos, todos sin significancia estadística (P>0.05). sólo en el caso de los estros detectados se encontró significancia estadística (P<0.05). Se concluye que para el caso de las cerdas nulíparas, es recomendable la utilización del Altrenogest para la sincronización del estro y con ello reducir el ciclo reproductivo de la hembra. En cuanto a las hembras primípara es posible evitar la utilización de productos exógenos o manejos especiales, si el manejo convencional en las áreas reproductivas es eficiente

Control y erradicación de la enfermedad de Aujeszky en un sistema múltiple de tres sitios de producción / Control and eradication of Aujeszky's disease in a multiple site production system

El objetivo del presente trabajo fue controlar y erradicar la enfermedad de Aujeszky (EA) en un sistema múltiple de tres sitios de producción por medio de la vacunación del hato reproductor contra la EA,, la segregación de la descendencia y hacer una valoraicón lineal epidemiológica de los tres sitios de producción mediante el uso de animales centinelas libres de la EA. La seropositividad en los tres sitios fue del 93.67 por ciento de las muestras totales tomadas (1389) en todo el sistema por la prueba de seroneutralización SN y ELISA competitiva g1. Para la erradicación de la EA se vacunó a las hembras con una vacuna con deleción g1+, siendo revacuadas a los 21 días y cada 3 meses durante el primer año posterior al brote al igual que a todo el hato, durante el segundo año se vacunó al pie de cría cada 4 meses. Por otra parte, durante el brote los lechones fueron destetados a los 21 días y llevados a otras instalaciones fuera del sistema y cuando los signos clínicos desaparecieron, los lechones fueron destetados a los 18 días y segregados al sitio 2. En la mayoría de los muestreos serológicos se obtuvo 0 por ciento de seropositividad, excepto en uno de éstos. En este sentido se tiene que los métodos aplicados en el sitio 1 (vacunación, medicación, cerrar la entrada de animales al sitio por un tiempo y la segregación de la descendencia) fueron efectivos para controlar y erradicar la enfermedad de Aujeszky en el sistema, ya que desde que se inició el programa no se presentó un solo caso de la enfermedad en los sitios 2 y 3 del sistema, como tampoco se observaron signos clínicos de la EA en el sitio 1

Efecto de dos quinolonas (nicotinato de norfloxacina y enrofloxacina) y del trimetoprim en combinación con sulfametoxazol en el tratamiento de enfermedades respiratorias (Actinobacillus pleuropneumoniae) / Comparative effeciency of two quinolones (Norfloxacin-nicotinate and Enrofloxacin) and trimetoprim with sulfametoxazole against the natural respiaratory infection by Actinobacillus pleuropneumoniae

Dentro de las enfermedades respiratorias una de las entidades más severas que afectan a los cerdos es el Actinobacillus pleuropneumoniae (App). El App causa pérdidas por mortalidad en cerdos de 12 a 16 semanas de edad, la morbilidad puede llegar hasta un 100 por ciento con una mortalidad que varía del 20 por ciento al 80 por ciento, aunque también las muertes pueden ocurrir en cerdos de mayor edad y peso. El estudio se realizó en una granja de ciclo completo, ubicada en el municipio de Huejotzingo en el estado de Puebla. Se alojaron 30 cerdos por corral con un peso de aproximadamente 18 kg. los tratamiento fueron: A) Nicotinato de norfloxacina a dosis de 5 mg/kg/día; y B) a dosis de 7.5 mg/kg/día. C) Enrofloxacina a dosis de 5 Mg/kg/día; y D) a dosis de 7.5 mg/kg/día, cada uno de ellos con un grupo testigo al cual no se le aplicó nada; E) la mezcla de sulfametoxazol con trimetorpim a dosis de 13.3 y 2.6 mg/kg/día, respectivamente, este grupo no contó con grupo testigo. El estudio tuvo una duración de 14 días, durante los cuales se estableció la siguiente rutina: el día 0 se realizaron 2 necropsias por grupo, con el objeto de determinar la existencia de la bacteria (App), haciendo un total de 10; del día 1 al 5 se administraron los antibióticos a las dosis antes mencionadas. Los signos observados durante los 14 días fueron: tos estornudo, fiebre, diarrea y mortalidad. El día 15 se realizaron 10 necropsias más, una de cada lote tratado, otra de cada lote testigo y dos más del grupo E por no existir lote testigo. Al analizar la incidencia de la enfermedad, el resultado fue que no se encontró significativamente estadística (P> 0.05) al analizar entre grupos, sólo se encontro significancia estadística en el grupo D al comparar el lote tratado con el lote testigo (P < 0.05)