InVet (Veterinary Research)

Microbiological study of effluents from artisanal cheese factories

Fri, 30 May 2025 00:00:00 +0000

In Tandil (Buenos Aires province) there are artisanal cheese factories, which are mostly located in rural
areas. Seven cheese factories were selected, and sampling was carried out for 4 years to evaluate the
microbiological quality of their effluents. Different ways of effluent disposal were identified: by direct
discharge to the environment, or with a system of pools or stabilization lagoons. A total of 41 samples
were microbiologically analyzed and the contents of thermotolerant coliforms were compared to the
limits of the regulations by the Water Authority of the province of Buenos Aires. The results showed
that 50% of the samples exceeded the required limit of thermotolerant coliforms. Escherichia coli,
Enterococcus spp., and other enteric bacteria were also found in some of the samples. The problems
encountered in the discharges were related to the lack of adequate advice to adopt efficient treatment
systems and also to the cost involved in their implementation.

Bone remodelling: age-related changes in markers of bone formation and resorption associated with falling oestrogen levels in female rats

Tue, 24 Jun 2025 00:00:00 +0000

Biochemical markers identify the level of bone remodelling. The aim was to determine the levels of CTX, OCN and the OCN/CTX ratio as a function of age and to assess changes due to ovariectomy-induced
oestrogen deficiency (OVX) in female Wistar rats. OCN and CTX were assessed and the OCN/CTX ratio was calculated in newborn, 21, 45, 60, 90, 105 and 150-day-old animals (n=8/group). The percentage change (%) from the newborn level was determined. OVX and SHAM rats were fed either Commercial diet or AIN-93M. OVX was performed at 45 days of age and proximal tibial BMD change (by DEXA) was assessed at 90 days in rats fed AIN-93M. OCN and CTX levels and OCN/CTX ratio were compared between the two groups at 90 and 105 days of age. OCN increased and CTX showed progressive decreases with age, stabilising at 90 days. The OCN/CTX ratio peaked at 90 days and decreased thereafter. OVX increased OCN in rats fed AIN-93M and did not vary with commercial diet; CTX increased with both diets. OVX decreased proximal tibia BMD relative to SHAM. Conclusions: Markers varied with age and the increase by OVX was diet-dependent, highlighting the importance of calcium, phosphorus and their relationship for bone health. Absolute values of OCN and CTX would allow establishing reference levels in female rats fed with commercial diet.

SARS-CoV-2 in dogs: gamma variant and its transmission from humans in Ciudad de Buenos Aires, Argentina

Wed, 25 Jun 2025 00:00:00 +0000

This article explores SARS-CoV-2 infection in dogs that have had close contact with humans diagnosed with COVID in Argentina. Affirmative molecular identification of the virus was achieved through RT-PCR analysis of oropharyngeal and rectal swabs from the dog as well as a nasal swab from the guardian. Positive results for the dog were confirmed through a LAMP/CRISPR assay and real time PCR. SARS-CoV-2 genomic RNA was successfully obtained from these samples, and the analysis of a partial sequence of the spike gene (ranging from amino acid 428 to 750) allowed us to classify both genomic sequences as Gamma variants, with a single amino acid variation in position 726. We evaluated the specific humoral immune response of the dog by an indirect ELISA using the Argentinian kit COVID AR IgG ELISA test adapted for domestic dogs, and pseudo-neutralization conducted with SARS-CoV-2 pseudotyped particles. We also evaluated the specific cellular immune response of the dog through a lymphoproliferation assay, using purified spike protein as specific stimulus. This work provides evidence of the human-to-dog transmission of SARS-CoV-2 in Argentina, underscoring the One Health concept and reinforcing surveillance methods in pets.

Residues of organic contaminants in honey from four villages in Buenos Aires province

Fri, 27 Jun 2025 00:00:00 +0000

The province of Buenos Aires is the leading honey producer in Argentina. The quality of the honey is a critical factor in its commercialization, particularly for export; therefore, the potential contamination by pesticides is a significant concern in honey production. In this context, a survey of honey samples from this province was conducted, identifying the presence of 36 pesticide residues and/or their metabolites. The objective of this study was to analyze the presence of organic xenobiotics in honey and to compare the results based on the predominant anthropogenic activities in each surveyed area. The results for all pesticide residues and their metabolites were found to be below the detection limit (LOD) of the corresponding analytical method, ensuring the purity of the honey in relation to these organic contaminants.

Obtención de cachemira por administración de extracto natural con mimosina y malla de contención como método de cosecha

Fri, 04 Jul 2025 00:00:00 +0000

Cashmere is obtained through combing, which, due to the variation in shedding patterns among animals, requires up to three repetitions and is difficult to optimize. Shearing must be done before the spring molt, and the goats are sensitive to low temperatures. A method of synchronized, uniform harvesting with animal welfare is needed. To modify the molting of cashmere goats, there are no available physiological techniques, except for the use of mimosine, which must be applied according to the seasonal follicular cycle of the skin, with appropriate means. The objective was to analyze the method of administering Leucaena leucocephala extract with mimosine and a covering mesh for cashmere production. Creole adult
goats at 35° S, in a semi-extensive system in La Pampa, Argentina, were treated with a single dose of 500 mg of mimosine/kg of live weight, orally, and with a containment mesh. In this way, mimosine has an effect lasting no more than 24 hours, causing total shedding of fine fiber without significantly affecting the coarse fiber; no clinically detectable toxic effects were observed. The mesh is fundamental for the viability of the method, and the obtained fiber has textile suitability and superior discard behavior compared to other harvesting methods.

Chitosan hydrogels crosslinked with glyoxal as controlled drug release systems

Tue, 05 Aug 2025 00:00:00 +0000

Chitosan hydrogels have garnered attention as transdermal drug delivery systems due to their ability to
facilitate controlled release of bioactive compounds, achieving systemic therapeutic effects. In this study,
we synthesized and characterized chitosan hydrogels crosslinked with glyoxal, targeting their potential as controlled drug release systems in animal production. The hydrogels were extensively characterized using Fourier Transform Infrared Spectroscopy to identify functional groups and confirm the successful incorporation of insulin. Swelling studies demonstrated a maximum swelling ratio of 4155 % at acidic pH, indicating significant water uptake and potential for drug delivery applications. Biocompatibility assessments, including hemolysis and MTT assays, revealed a hemolysis percentage below 10 % and cell viability exceeding 95 % after 24 and 48 hours, underscoring the hydrogels’ safety profile. Insulin incorporation efficiency was 95.99 %, with a sustained release profile reaching a maximum of 13.19 % at 27 hours. These findings suggest that chitosan-based hydrogels crosslinked with glyoxal hold promise as effective platforms for slow or sustained transdermal drug delivery, particularly for therapeutic agents requiring prolonged release.

Detection of Salmonella spp. and enterobacterias in egg for consumption from cage-free systems

Zulma Canet, Olga Riva, Jose Daniel Rodriguez, Martin Andersen — Fri, 27 Jun 2025 00:00:00 +0000

The presence of Salmonella spp. and the Enterobacteria count were studied in eggs from hens housed in cage-free systems on 30 farms in the province of Buenos Aires and southern Santa Fe. The analyses carried out to detect the presence of Salmonella spp., both on the shell and inside the egg, were negative. Regarding the Enterobacteria count, they were isolated in most of the eggs with colony count values within the permitted range, except for 4 % of the farms where higher values were detected. In these cases, it was recommended to improve biosecurity measures that also consider the safety of the eggs. These microorganisms can not only cause economic losses in poultry production, but also represent a risk to public health. The results indicate that if the cage-free production system incorporates good poultry practices, the eggs produced are of excellent microbiological quality.