The success of artificial insemination (AI) with frozen–thawed semen in cattle is influenced by both female factors and sperm quality. In terms of sperm quality, prior studies indicate that the ability of frozen–thawed bovine sperm to fertilise an oocyte is dependent on their quality and resilience to cryopreservation. Cryopreservation induces oxidative stress, leading to ultrastructural damage in the sperm. This study aimed to determine whether the quality of fresh semen can identify bulls with good and poor sperm freezability. This difference between fresh and frozen semen from the same bull allows us to predict fertility. Motility and kinetic parameters were assessed using computer‐assisted sperm analysis (CASA), while six functional variables were evaluated through flow cytometry, both before and after the freeze–thaw process on the sperm from 13 bulls. In vivo fertility was measured using 90‐day non‐return rates. The principal component analysis (PCA) of eight sperm variables post‐thaw identified one principal component explaining 81.19% of the total variance and classified the bulls into two groups: Poor freezability bulls (progressive motility: 48.12% ± 8.41%; viability: 77.51% ± 7.61%) and good freezability bulls (progressive motility: 58.64% ± 6.64%; viability: 88.12% ± 2.52%). Bulls with higher freezability showed better sperm viability and motility, as well as lower levels of ROS, superoxides and intracellular calcium before cryopreservation that were significantly correlated with higher non‐return rates (NRR). The results underscore the importance of assessing the quality and functionality of fresh semen to predict the fertility potential of cryopreserved sperm. This approach can aid in selecting ejaculates with the best potential for successful artificial insemination, ultimately improving reproductive performance in dairy cattle.

Acute abdomen (AA) is the term used to define a pathological condition that affects the abdominal cavity and frequently manifests itself with acute clinical symptoms capable of compromising a cow’s life. Therefore, it should be considered as an emergency that should be evaluated as quickly as possible to adopt the appropriate therapeutic measure (medical or surgical). In an AA situation, the clinician must consider the appropriate diagnostic approach as well as the therapeutic choice. Given the emergency, the veterinarian’s experience will be decisive for the appropriate resolution. In this article, we briefly review the causes that may lead to this condition, as well as the different diagnostic tests available in field conditions to establish the correct diagnosis and treatment.

The objective of this work was to determine productive and fertility responses of Holstein-Friesian heifers and cows to supplementation with extruded linseed and soybean as sources of polyunsaturated fatty acids (PUFAs). Supplementation had a positive effect on profitability, with significant increases in milk yield in supplemented cows, but not in heifers. Treatments had no effect on milk fat content, but higher milk protein contents were observed with supplementation. A higher conception rate was found for supplemented heifers, but not for cows. Fat sources containing PUFAs are recommended for dairy cattle supplementation, since they improve fertility in heifers and milk yield in cows.

To the best of the authors' knowledge, no study has previously investigated whether the concentration of minerals is related to reproductive outcomes in primiparous cows. For this reason, two objectives were set in the present study: (i) to assess serum mineral levels, macrominerals, and trace elements during the transition period (period of high nutritional requirements) in primiparous cows, considering reproductive efficiency, and (ii) to address if the serum mineral levels of primiparous cows are related to reproductive efficiency. Blood samples were taken (i) one month before calving, (ii) one week before calving, (iii) one week postpartum, and (iv) one month postpartum. At the beginning and the end of the study, a body condition score (BCS) was assigned to each lactating cow with no clinical signs of disease. The difference between one month before and one month after calving was the body condition loss (ΔBCS). Optimal prepartum concentrations of K and Cl were associated with fewer days open and a shorter interval calving. Furthermore, macrominerals in the serum decreased immediately after calving (one week) but recovered at one month postpartum. In contrast, the highest concentration of trace elements was found at one week postpartum. Primiparous cows with higher postpartum Se, Mn, Co, and Mo concentrations exhibited better reproductive efficiency, and the concentrations of trace elements in serum were correlated with interval calving and the number of inseminations. Finally, primiparous cows with a greater ΔBCS (at least one point) in period 4 exhibited both a longer calving interval and a greater number of days open. In summary, this study showed, for the first time in primiparous cows, that the concentration of some serum minerals not only plays a crucial role during the transition period but is also related to crucial reproductive parameters, such as interval calving and days open.

MFD is a nutritional disorder in dairy cattle characterized by a reduction in milk fat content despite a normal or increased milk yield. This review synthesizes current knowledge on the biological mechanisms and nutritional factors contributing to the development of this condition. Disruptions in rumen fermentation and alterations in fatty acid biohydrogenation (particularly the formation of trans-10 fatty acids) are recognized as central contributors to MFD. Several theories have been proposed to explain its pathophysiology, including the glucogenic, volatile fatty acid, trans fatty acid, and biohydrogenation theories. MFD is most commonly associated with diets low in fiber and high in polyunsaturated fatty acids or starch, which promote the accumulation of fatty acid intermediates that inhibit mammary lipogenesis. Among these, trans-10, cis-12 conjugated linoleic acid is particularly notable for its potent suppression of de novo fatty acid synthesis in the mammary gland. While proper dietary formulation remains the most effective preventive strategy, nutritional interventions such as magnesium-based alkalinizers, sodium bicarbonate, intravenous arginine, and vitamin E have shown promise in mitigating established cases. This review underscores the importance of nutritional management in preserving milk fat synthesis and promoting overall animal health.