Fixed-time artificial insemination (FTAI) is a reproductive technology that aids in obtaining an appropriate time to perform single artificial insemination (AI), thus reducing the number of inseminations per sow bred. FTAI protocols can either be based on estrus detection or day of weaning, aiming to synchronize ovulation using ovulation inducers. The protocols involving estrus detection usually employ porcine luteinizing hormone (pLH) as an inducer and, in general, satisfactory reproductive performance is observed. For protocols based on weaning day, the main hormone used is analog of gonadotropin-releasing hormone such as triptorelin and buserelin. Regardless of the protocol, the number of piglets born is usually not affected by FTAI. However, a possible compromise in the farrowing rate should be considered. The FTAI in gilts requires progestogen treatment for estrus synchronization, increasing the labor requirement and cost of protocol. Some of the benefits of FTAI are a reduced number of semen doses required, advantage of planning the breeding time and; consequently, optimizing labor involved. However, the limitations include a slight reduction in the fertility index due to the compromised farrowing rate in some cases, costs incurred by following the protocol, and difficulty in measuring all the conceptual benefits under commercial conditions. The aim of this review is to approach the reproductive performance of the current protocols of FTAI, considering the benefits and limitations of this technology in swine production.

This study evaluated the acute and subchronic toxicity of pure potassium sorbate and investigated the genotoxic, hematological, biochemical, and histopathological effects of commercial formulations based on this preservative in rodents. The toxicity of pure potassium sorbate was assessed following OECD 425 and 407 guidelines. The commercial formulations Golden Blue, Aquafiv, and Aquativagro were evaluated through comet assays (in L929 cells) and micronucleus tests, alongside hematological, serum biochemical, and histopathological examinations of the liver and kidneys. No mortality or significant body weight alterations were observed with pure potassium sorbate, indicating an oral LD50 above 1,100 mg/kg. Commercial formulations showed no genotoxic effects. However, significant reductions in erythrocyte, total leukocyte, and monocyte counts were observed, accompanied by decreased serum ALT and AST activities and increased creatinine concentrations. Histopathological analyses revealed glomerular congestion, tubular swelling, vacuolar degeneration, hepatic vascular congestion, and microvesicular steatosis. In conclusion, pure potassium sorbate exhibited low acute toxicity, while commercial formulations induced distinct hepatorenal and hematological alterations, highlighting the need for further safety assessments.

Cats with urethral obstruction may develop tubular damage before conventional indicators of renal dysfunction become abnormal, making early recognition challenging when relying solely on conventional renal biomarkers. This study evaluated urinary kidney injury molecule-1 (KIM-1) concentrations in non-azotemic cats with urethral obstruction and compared its expression with conventional renal biomarkers. Twenty-four male cats were prospectively enrolled and allocated into a control group (n = 12) and a urethral obstruction group (n = 12), all presenting serum creatinine concentrations within the reference interval. Urinary KIM-1 concentrations were quantified by enzyme-linked immunosorbent assay (ELISA) and normalized to urinary creatinine concentrations. Serum creatinine and blood urea nitrogen (BUN) did not differ significantly between groups. In contrast, urinary KIM-1 concentrations were significantly higher in cats with urethral obstruction compared with healthy controls (p < 0.001). These findings suggest that increased urinary KIM-1 expression may be associated with renal tubular injury in non-azotemic cats with urethral obstruction, even in the absence of alterations in conventional renal biomarkers. Therefore, urinary KIM-1 may represent a useful non-invasive marker of renal tubular injury associated with obstructive urinary disease. Further prospective studies incorporating additional renal biomarkers, histopathological evaluation, and longitudinal follow-up are warranted to better define its clinical applicability.