This work aimed to evaluate intrinsic and extrinsic factors influencing in vitro embryo production (IVEP) efficiency in bovines under tropical conditions in Colombia. Retrospective data from 1 443 ovum pick-up (OPU) sessions conducted between 2020 and 2021 involving Brahman, Gyr, and Holstein cattle breeds were analyzed. Variables assessed included oocyte viability, cleavage rate, blastocyst yield, semen type (sex-sorted vs. conventional), IGF-I supplementation, seasonal climatic conditions, breed, and frequency of follicular aspiration. Results indicated significant effects of these factors on IVEP efficiency. The rainy season improved oocyte quality and embryo production, yielding a higher blastocyst rate per OPU (23.9 %) compared to dry (21.6 %) and transition seasons (19.6 %). The geographic location influenced all IVEP parameters, with higher embryo production rates in Montería compared to other regions. Conventional semen significantly increased embryo production rates (25.8 % Blast/OPU) compared to sex-sorted semen (17.9 % Blast/OPU). Supplementation with 100 ng/ml IGF-I significantly enhanced cleavage rates (76.3 %) and blastocyst yields (27.3 % Blast/OPU). While Brahman cows provided the highest number of oocytes, Gyr and Red Brahman breeds exhibited superior embryo development potential. Additionally, frequent follicular aspiration intervals (≤ 4 times) resulted in better embryo production compared to less frequent aspirations (> 5 times). These findings highlight critical factors for optimizing IVEP protocols under tropical conditions, suggesting strategic adjustments such as scheduling OPU sessions during favorable seasons, selecting suitable breeds and semen types, utilizing IGF-I supplementation, and optimizing follicular aspiration frequency to enhance embryo production efficiency in commercial cattle breeding programs.
This study aimed to produce two functional feed additives via solid-state fermentation and evaluate their effects on performance, meat quality, and cecal microbiota in broiler chickens. A total of 288 mixed-sex Ross 308 broiler chicks were randomly assigned to nine dietary treatments (four replicates of eight chicks each). The control group received a basal diet, while treatment groups received the basal diet supplemented with increasing doses (300–2 400 mg/kg) of either fermented tomato pomace plus oat or fermented apple pomace plus rye. The trial lasted 49 days. Supplementation with the lowest and highest doses of fermented apple pomace plus rye significantly increased body weight and body weight gain (P < 0.05). The fermented tomato pomace plus oat increased breast meat lightness and yellowness at higher doses, whereas the fermented apple pomace plus rye decreased both color parameters (P < 0.05). The cecal lactic acid bacteria population increased with both additives at 300 mg/kg (P < 0.05). Both fermentation products yielded functional additives that improved body weight and weight gain during the starter period. The fermented apple pomace plus rye at 300 mg/kg showed the most consistent positive effects and can be recommended as a potential alternative feed additive for broiler chickens.
Feline immunodeficiency virus (FIV) is a retrovirus that infects domestic cats. Genetic variability of the virus, particularly in the V3–V5 region of the envelope gene, may contribute to amino acid changes that affect viral pathogenicity and the development of eight distinct subtypes. The circulating genotype and nonsynonymous mutations in an env gene fragment were analyzed in domestic cats from Colombia. Blood samples were collected from 151 felines, and an 859‑base pair fragment of the env gene was amplified and sequenced. Phylogenetic analysis identified genotype A as the circulating genotype; however, sequences clustered into different clades within this genotype. Twelve nonsynonymous amino acid substitutions were detected, of which H86R, N88K, E41V, and K91D showed a high probability of having a deleterious impact. These findings highlight the genetic diversity within FIV genotype A and underscore the potential impact of specific nonsynonymous mutations on viral pathogenicity.
Erysipelothrix rhusiopathiae is known to cause infections in humans following exposure to decaying organic matter or animals colonized with the organism, such as swine and fish. The aim of this study was to investigate the occurrence of this bacterium in companion birds in Iran. A total of 116 stool and tissue samples were collected from pigeons, cockatiels (n = 14), Grey Parrot (Psittacus erithacus), Red-and-green Macaw (Ara chloropterus) and Singing Parrot (Geoffroyus heteroclitus) admitted to veterinary clinics in Tabriz, Yazd, and Ahvaz. To investigate the presence of E. rhusiopathiae at the molecular level, DNA was extracted from all samples followed by PCR testing. After euthanasia, tissue samples were taken from the sick birds for histopathological examination. PCR analysis of tissue samples (trachea and brain) from two immature female pigeons yielded positive results for E. rhusiopathiae, representing a detection rate of 2.02 % (2/99) among birds from which tissue samples were collected. Histopathological examinations revealed necrotizing hepatitis, nephritis, myocarditis, rhabdomyolysis, pneumonia, and mild tracheitis with severe hyperemia, focal hemorrhages and varying degrees of inflammation in the examined tissues. From these results, it could be assumed that E. rhusiopathiae is present in the trachea and brain of Iranian companion birds, especially pigeons, as an important infectious agent that can have serious effects on the health and stability of these avian populations.
This study investigated phenotypic antimicrobial resistance in bacterial isolates from clinical samples of dogs and cats in southern Chile between 2021 and 2022. A total of 140 samples (109 from dogs, 31 from cats) were analyzed. Bacterial identification and antimicrobial susceptibility testing were performed using standard biochemical methods and Kirby-Bauer disk diffusion, interpreted according to The Clinical & Laboratory Standards Institute guidelines. The most frequent sample types were skin in dogs (50.5 %) and urine in cats (38.7 %). Coagulase-negative staphylococci (29.3 %), Escherichia coli (20.7 %), and Staphylococcus aureus (17.9 %) were the most commonly isolated bacteria. Multidrug resistance (MDR) was observed in 52 % of S. aureus and 51.7 % of E. coli isolates. Two isolates showed profiles suggestive of extended-spectrum β-lactamase (ESBL) production. E. coli exhibited resistance to all tested antimicrobials except imipenem. These findings reveal worrisome resistance patterns in companion animals in southern Chile and underscore the urgent need to integrate these species into regional antimicrobial resistance surveillance efforts.
Advancing sustainable beef systems requires understanding the carbon footprint of livestock production. Mexico is responsible for high greenhouse gas (GHG) emissions from the livestock sector, an activity that extends across large areas of land in its tropical region. This study aimed to assess the contributions of two cattle grazing systems to climate change and to their carbon (C) sequestration potential, as well as to estimate their GHG balance. The analysis was conducted in accordance with the ISO 14067 standard based on the Life Cycle Assessment methodology. The “cradle-to-farm gate” approach was applied to evaluate the carbon footprint of 1 kg of live weight of calf, including C sequestration in two beef cow-calf grazing systems in the Mexican tropics: monoculture (MC) and silvopastoral (SP). Data collected from six cattle ranches (three monoculture and three silvopastoral), in the State of Yucatán, Mexico, were used. The system boundaries included pasture, feed supplements, agrochemicals, fossil fuels, electricity, and pesticides. The potential soil C equestration was estimated from the Ex-Ante Carbon-balance Tool version 9 of the Food and Agriculture Organization of the United Nations. The results revealed that MC systems exhibited lower GHG emissions than the SP, while soil C equestration was higher in the SP. The carbon balance shows a lower carbon footprint for the SP than the MC system, and the uncertainty analysis demonstrates that the SP system had lower variability than the MC. The outcomes of this study could be used to direct policies aimed at reducing the contribution of tropical grazing systems to climate change.
The morphological development of the adrenal and thyroid glands was evaluated in fetuses of Red Sokoto goats (Capra hircus) using anatomical techniques. Forty apparently healthy pregnant goats were grouped into first term (0–50 days), early second term (51–75 days), late second term (76–100 days), and third term (101–150 days). The oval, light-pink, paired adrenal glands showed poorly formed parenchymal zones by fetal day (FD) 57. By FD 69, the cortex and medulla were formed, and their thickness increased steadily with age. At FD 102, the adrenal cortex exhibited thin outer, middle, and inner layers, while the adrenal medulla changed from naive cords of cells in the early second term to pale-staining cords bounded by wide sinusoidal spaces towards full term. Thyroid follicle diameter increased linearly with age, with widening lumina filled with colloid. Follicular epithelium consisted mostly of follicular cells; later in the third term, parafollicular cells appeared singly or in clusters within interfollicular connective tissue. These structural changes suggest that the adrenal gland is prepared for adult function, and the thyroid assumes adult morphology early in fetal life, essential for normal physiology in fetuses and postnatally.
This study compared two methods for estimating milk yield (MY) in multiparous Pelibuey and Katahdin ewes accounting for litter size and week of lactation under tropical conditions. MY was assessed using the weight-suckle-weight (WSW) technique and hand milking (HM). Exploratory analysis was performed using box plots, followed by a repeated-measures ANOVA based on a mixed linear model including method, breed, litter size, and week as fixed effects, and ewe as a random effect. Method agreement was evaluated using Bland–Altman analysis. MY increased during the first three weeks of lactation, then stabilized or slightly declined. HM consistently produced higher average values than WSW. Katahdin ewes and those rearing twin litters yielded more milk than Pelibuey and single-litter counterparts. The mixed model showed that estimation method and litter size were the main sources of variation, followed by breed and week. The intraclass correlation coefficient (ICC = 28.11 %) indicated that slightly more than one-quarter of total variability was attributable to individual differences. The means ± SE plot suggested an interaction, with the largest HM–WSW discrepancy observed in Katahdin twin-litter ewes, the highest-producing group. The Bland–Altman plot revealed a systematic bias (-0.78 kg; HM > WSW) and poor agreement (limits of agreement -2.26 to 0.66 kg), indicating potential individual-level discrepancies. HM tends to overestimate MY relative to WSW, particularly in highly productive ewes. The two methods are not interchangeable without adjustment; their selection should consider ewe characteristics and study objectives, and correction for systematic bias is recommended when comparing results.
The effectiveness of eprinomectin and levamisole was evaluated in a dairy goat herd in El Bajío with a history of multi-resistance to fenbendazole (0 %) and ivermectin (70 %) using the Fecal Egg Count Reduction Test. Larval cultures were used to assess the epidemiology of the disease. Thirty goats with ≥ 150 eggs per gram (EPG) and no anthelmintic treatment for ≥ 60 days were selected. The modified McMaster technique (sensitivity: 50 EPG) was used to quantify the parasite burden. Three groups (n = 10) were weighed and treated: eprinomectin (0.5 mg/kg, topical), levamisole (12 mg/kg, subcutaneous), and an untreated control. The effectiveness of eprinomectin was 65 %, while that of levamisole was 100 %. Trichostrongylus spp. (90–100 %) and Oesophagostomum sp. (10 %) were identified. The reduced effectiveness of eprinomectin may be linked to ivermectin resistance. Multidrug resistance in small ruminants highlights the urgent need for targeted selective treatments and integrated parasite management to preserve effective anthelmintics.
La presencia de patógenos que afectan al tracto respiratorio del cerdo es frecuente en poblaciones porcinas de todo el mundo y su importancia radica en el impacto económico que ocasionan, debido a su alta morbilidad, posible mortalidad y pérdidas productivas. Las granjas porcinas de pequeña escala (GPE), al operar con limitadas condiciones de bioseguridad, podrían favorecer la circulación y diseminación de patógenos respiratorios, afectando su productividad. El objetivo de este estudio fue determinar la presencia de anticuerpos contra Actinobacillus pleuropneumoniae (App), Mycoplasma hyopneumoniae (Mhyo), el virus del Síndrome Reproductivo y Respiratorio Porcino (PRRS) y el virus de Influenza porcina (IP [H1N1 y H3N2]) en cerdos de GPE ubicadas en el centro de México. Se recolectaron 66 muestras sanguíneas de cerdos en distintas etapas productivas en seis granjas con producción de ciclo completo, y se analizaron mediante pruebas serológicas. Las frecuencias de seropositividad fueron IP H1N1 (92.4%), App (43.9%), IP H3N2 (40.9%), Mhyo (39.4%) y PRRS (13.6%). Se observó una asociación significativa entre la seropositividad a App y la etapa productiva (P<0.01), con mayor frecuencia en cerdas reproductoras y de reemplazo. También se identificaron asociaciones serológicas entre Mhyo e IP H3N2 (P=0.02), y entre IP H3N2 y PRRS (P<0.01). Estos hallazgos evidencian una alta exposición a patógenos respiratorios en GPE, atribuible a la falta de medidas sanitarias y de manejo adecuadas. Se destaca la necesidad de fortalecer la vigilancia epidemiológica y la extensión veterinaria para mitigar los riesgos sanitarios y productivos en estas unidades.
Pelagic sargassum is a mixture of several species of brown macroalgae rich in minerals, polysaccharides, and bioactive compounds; it reaches the Caribbean coasts in large quantities. The objective of this study was to evaluate its potential as an ingredient in ruminant feed based on its in situ degradability and in vitro gas production. 0 %, 10 %, 20 %, and 30 % percentages of sargassum were added to a substrate (Pennisetum purpureum VC CT-115 hay). Two cows with ruminal cannulas were used for the in situ trial, while in vitro gas production was evaluated following the Menke and Steingass methodology. The inoculum was an aliquot of ruminal fluid obtained through an esophageal probe from five grazing hair sheep. In situ degradability of dry matter (DM) decreased linearly (P < 0.0001) as the concentration of sargassum in the substrate increased from 0 % to 30 % (48 h: from 684.91 to 607.75 g/kg DM; 72 h: from 722.10 to 634.68 g/kg DM); organic matter (OM) showed a comparable trend. While the in vitro gas production curve was among the control group, 10 % and 20 % levels of inclusion, degradability of DM and OM, as well as the protozoa population, were did not differ significantly (P > 0.0001) across all treatments. We conclude that pelagic sargassum may be included at levels of 20 % and 30 % in situ and in vitro; however, its use under in vivo conditions requires further evaluation.
The objective of this study was to determine the relationship between body weight (BW) and body condition score (BCS) in non-pregnant, non-lactating Katahdin ewes under tropical conditions. Body weight and BCS were measured in 110 Katahdin ewes aged 2.5 years with mean BW of 43.18 ±6.73 kg and mean BCS of 2.38 ±0.82. Relationships were analyzed using correlation and linear regression. Body weight and BCS showed a strong positive correlation (r = 0.90; P < 0.001). The linear regression equation was BW = 25.66 (±0.84) + 7.34 (±0.33) × BCS (R² = 0.81, MSE = 8.39, RSD = 2.89, n = 110). These results indicate that 7.34 ±0.33 kg of BW are required for each unit change in BCS in Katahdin ewes managed under humid tropical conditions.
The clinical efficacy of salinomycin premix (Pisacox®) administered in feed to replacement pullets to control coccidiosis was evaluated by dosing during 4 or 14 weeks. The productive performance, signs, and lesions associated with coccidiosis and direct oocyst counts were analyzed in 3 000 Bovans White pullets distributed in 3 groups of 1 000 birds having the same diet: control group (Ctrl) without coccidiostat; Sal4 group with the administration of salinomycin for 4 weeks; and Sal14 group that received salinomycin for 14 weeks. Predictably, in both Sal4 and Sal14 treatments, lower oocyst counts than in the control were observed. However, it was more evident with Sal14 towards the end of the trial, whose oocyst count was < 5 000 g of feces. This response can be associated with better productivity variables. The coccidial-type intestinal lesions detected in control were classified as severe (2.55), while Sal4 and Sal14 presented values of 1.0 and 0 (mild lesions and normal appearance, respectively). The accumulated mortality associated with coccidiosis was statistically higher in the Ctontrol group (9.8 %) (P < 0.001), 1.33 % for Sal4, and 0.2 % for Sal14 (P < 0.05, between these two groups). In conclusion, using salinomycin for 4 weeks successfully controls clinical coccidiosis. However, the lower rate of coccidiosis, the improvement in productive variables, and the lower accumulated mortality in Sal14 allow for the proposal of including the treatment with salinomycin for 14 weeks in replacement pullets.
La conservación de los recursos genéticos animales se considera un pilar para la seguridad alimentaria y el desarrollo rural mexicano; sin embargo, algunas poblaciones están en riesgo de desaparecer, como la de los cerdos criollos, que se concentran en un núcleo productivo rural muy pequeño, donde la alta mortalidad y la productividad de los lactantes reflejan las limitaciones. Primero, cuando los lechones nacieron, se pesaron (PN) y se tomaron sus medidas zoométricas: circunferencia cefálica (CC), circunferencia abdominal (CA), circunferencia torácica (CT), longitud corporal (LC), e índices zoométricos: índice de masa corporal (IMC) e índice ponderal (IP) de neonatos criollos ts´üdi xirgo. Mediante la construcción de modelos de regresión multivariable, se buscó la agrupación de variables, que permitan identificar lechones con mejores valores en las características productivas durante la lactancia: peso el día 21 (P21), peso al destete (PD) y ganancia diaria de peso (GPD). Se consideró que las agrupaciones incluyeran una variable zoométrica y un índice zoométrico al nacer como variable fija, y los días de lactancia (DL) como bloque. Algunas de las variables que influyen en la productividad de los lechones criollos son las características físicas. Hallamos que el conjunto de variables PN, CT, IP y DL brinda una mejor predicción para el P21 (P = 0.001) y el PD (P = 0.003), mientras que, para la GPD, las variables que se ajustan a los datos son PN, LC, IP y DL (P = 0.01). El uso de herramientas y protocolos para la identificación temprana de lechones en riesgo permite brindar las condiciones óptimas para una lactancia y un desarrollo eficaces, disminuyendo la mortalidad predestete, favoreciendo el incremento nacional de estos animales y sirviendo como impulso y apoyo económico para las familias productoras de cerdo criollo.
Specific sensitive diagnostic markers for early diagnosis of canine pyometra have been widely attempted, but none have proven to be a perfect diagnostic marker for clinical practice. Lipopolysaccharide (LPS) or endotoxin is a cell wall component of gram-negative bacteria, released during bacterial death. The early release, inherent stability, and serotype-specificity of endotoxin suggest its potential as a good candidate for early diagnosis of pyometra. The present study focused on understanding the potential of LPS as a diagnostic and prognostic marker in canine pyometra. The study also tried to establish the correlation between bacterial isolates cultured from the vaginal discharge and endotoxin levels. A total of 12 animals presented to University Veterinary Hospitals with open and closed-cervix pyometra were selected and divided into two groups of six dogs each. Serum LPS concentration (ng/mL) was estimated on various days of observation using ELISA. Mean serum LPS concentration was higher in both groups on the day of presentation, and significantly higher levels were observed in animals with closed-cervix pyometra. Bacteriological examination revealed a predominance of gram-negative organisms in both groups. Hence, it establishes LPS as a better diagnostic marker of canine pyometra. Conversely, a reduction in the levels of LPS on subsequent days of observation confirms its efficacy as a prognostic marker.
El objetivo de esta investigación fue caracterizar la calidad fisicoquímica y microbiológica de la leche y el queso fresco (“cuajada”) de ganado bovino elaborado en el Istmo de Tehuantepec, Oaxaca, México, así como analizar los sistemas de producción pecuarios asociados a su elaboración. De cada sistema de producción se evaluaron 10 L de leche cruda bovina y 10 muestras de queso fresco (500 g cada una), y se determinaron parámetros microbiológicos y fisicoquímicos. Los productores en los sistemas de producción tienen entre 43 y 72 años y estudios de nivel superior concluidos. Los hatos bovinos oscilaron entre 64–187 cabezas con razas dominantes de Cebú (Bos indicus), Suizo e Indubrasil (Bos taurus × Bos indicus) con una producción de 100–168 litros de leche diarios. Los resultados mostraron que la leche y la cuajada no cumplen con los estándares microbiológicos de la normativa mexicana. En cuanto a las propiedades fisicoquímicas, la humedad del queso fue alta (50–61 %) y la proteína varió entre 17–35 %) y la grasa, 8–22 %. El análisis de color reveló alta luminosidad (L* 87–93) y tonalidad amarilla (b* 15–20), mientras que el perfil de textura indicó diferencias significativas en dureza (5–50 N) y cohesividad. Los hallazgos resaltan la importancia de capacitaciones técnicas para mejorar la calidad y seguridad de estos productos, preservando al mismo tiempo su valor cultural y tradicional.
Porcine sapelovirus (PSV), a member of the Sapelovirus genus within the Picornaviridae family, is a swine pathogen causing respiratory diseases, polioencephalomyelitis, and gastroenteritis. The infection results in economic loss in the swine industry and often co-occurs with bacterial, viral, or fungal infections. Despite its impact, the evolutionary dynamics and adaptation mechanisms of PSV remain poorly understood. This study investigates the evolutionary forces shaping adaptation of the PSV polyprotein gene through codon usage bias and nucleotide composition analysis. A total of 34 polyprotein coding sequences of PSV were retrieved from the NCBI database and analyzed using bioinformatics tools. The nucleotide composition analysis revealed adenine as the most abundant nucleotide, with thymine predominating at the third codon positions. The Guanine-Cytocine (GC) content was balanced overall, with variations in GC content at the third codon position values suggesting mutational pressure. Relative synonymous codon usage analysis identified overrepresented and underrepresented codons, highlighting host-specific selection pressures. The Effective number of codons and neutrality plots indicated that natural selection predominantly influences codon usage bias in PSV, while mutational pressure contributes less. Chargaff's second parity rule analysis confirmed deviations influenced by these forces, while dinucleotide abundance analysis provided insights into codon usage trends. The codon adaptation index (CAI = 0.584) suggested moderate adaptation of PSV to its natural host, Sus scrofa domesticus, reflecting evolutionary constraints on translational efficiency. Correspondence analysis highlighted factors driving viral evolution. These findings contribute to our understanding of PSV molecular evolution, supporting the development of antiviral strategies, vaccines, and diagnostic for disease control.
The evaluation of the cattle production system allows the diagnosis and suggestions of alternatives to improve production conditions. This study aimed to evaluate productivity and reproductive indicators and their relationship with the production systems in the parish of Guayzimi, canton of Nangaritza, in the province of Zamora-Chinchipe, Ecuador. A survey was conducted among bovine farmers in the study area, including questions related to social, productive, and reproductive aspects. A sample of 35 producers was analyzed using multivariate principal component analysis, descriptive statistics, correspondence analysis, and multiple correlation matrices Spearman's criterion. The results identified three main components: “Technical-Productive”, “Reproductive Efficiency”, and “Marketing,” which accounted for 35.1 %, 28.7 %, and 13.3 % of the total variance, respectively. Together, these components explained 77.7 % of the variance. The main issues identified were related to herd structure, showing a surplus of cows and bulls at 17.4 % and 78.6 %, respectively, and a deficit of heifers, calves, and young bulls at 21.3 %, 3.3 %, and 39.4 %, respectively. Additionally, a notable stagnation of females in the pre-reproductive stage suggesting they are not a significant variable in the production process. This study shows that achieving productive efficiency requires consideration of the relationship between 'herd organization + production organization + marketing” and the fact that stagnation in the flow of replacement female cattle is due to deficiencies in production strategies. Future studies could build on this research to strengthen the foundation of bovine production in the Guaizimi, Nangaritza, Zamora-Chinchipe.
This study aimed to analyze the milk performance of Arbia does, the predominant goat breed in Algeria. A total of 389 quantitative and qualitative milk control records were collected from sixty-six dairy Arbia does monitored throughout their complete lactation period. The animals, managed under similar livestock practices, were located in two different agroecological regions: arid (Ar) and semiarid (SAr). The average lactation length (DIM) and interval between kidding (IKI) were 195.82 ±60.42 and 250.55 ±69.55 days, respectively, with milk production peaking at 89.22 ±10.76 days postkidding. The study recorded an average Total Milk Yield (TMY) of 207.18 ±76.86 kg, Daily Milk Yield (DMY) of 1.05 ±0.2 kg, and Persistency Coefficient (PC) of 72.91 ±4.13 %. The average Total Fat Yield (TFY), Total Protein Yield (TPY), Milk Fat Rate (MFR), and Milk Protein Rate (MPR) were 219.72 ±95.05 g, 745.28 ±88.68 g, 1.94 ±1.13 %, and 4.11 ±1.67%, respectively. Does from SAr produced more TFY and comparable TPY compared to those from Ar, despite having lower TMY and shorter DIM, reflecting significantly higher MFR and MPR in SAr. While lactation length showed potential influence on TMY (P = 0.07) and significant effects on TPY (P < 0.05), other factors, such as age, lactation number, and animals' origin, did not significantly affect TMY. Analysis revealed one production profile in Ar and two distinct lactation production profiles in SAr, suggesting the need for tailored optimization strategies based on this diversity in milk production characteristics.
