Characterizing sow feed intake during lactation to explain litter and subsequent farrowing performance.

Variation in feed intake results in nearly 20% of sows consuming less than the recommended lysine (Lys) intake for lactating sows. The Lys requirement for lactating sows is based on litter size and piglet average daily gain which influences milk production. Litter size continues to increase every year causing the need for routine reevaluation of nutrient requirements. If dietary inclusion levels are not continuously adjusted this can lead to inadequate daily Lys and energy intake and may negatively impact sow body condition and litter performance. The objective was to characterize the average daily feed intake (ADFI) of sows and define feed intake patterns and their effects on sow body weight, farrowing performance, litter performance, and subsequent farrowing performance. ADFI during lactation was recorded for 4,248 sows from 7 independent research studies. Data collection occurred from November 2021 through November 2023 at a commercial breed-to-wean facility in western Illinois. Each sow was categorized as: consistently low intake (< 5.5 kg/d) throughout the lactation (LLL); low intakes (< 5 kg/d) in the first week, then gradually increased throughout the rest of the lactation period (LHH); gradual increase in intake throughout lactation with no drop and a peak intake after day 10 of lactation (gradual); rapid increase in intake with no drop and the peak intake met before day 10 (rapid); a major drop in feed intake (> 1.6 kg decrease for ≥ 2 d) any time during lactation (MAJOR); minor drop (≤ 1.6 kg for ≥ 2 d; MINOR). Sows were also separated into low (quartile 1; ≤ 25%), average (quartile 2 through 3), or high feed intake (quartile 4; ≥ 75%) by parity (P1, P2, P3+). Sows in the LLL category were younger in parity, had the greatest preweaned mortality, weaned the lightest average pigs, and experienced the greatest loss in body weight percentage compared with sows in all other feed intake categories. Furthermore, sows in the LLL and LHH categories had one fewer subsequent pig born compared with sows in the other four categories. These data support historical findings that feed intake patterns directly contribute to current litter farrowing performance. Lactation intake patterns also influence subsequent farrowing performance. Identifying under-consuming sows that are likely Lys and energy deficient allows producers opportunities to promote consistent, adequate daily intakes to these groups and mitigate negative impacts on sow and litter performance.

This study investigated different sow feed intake patterns during lactation and average daily feed intakes within parity on current and subsequent farrowing and litter performance. Findings revealed sows that have consistently low intake throughout the lactation period have a significant reduction in average pig wean weight, a greater percentage of pre-wean mortality, and take an additional day or longer to return to estrus compared with sows that have average or above feed intake throughout the lactation period. Specifically, older parity sows were heavier, had greater feed intake, nursed heavier litters, and had litters with less preweaned mortality compared with younger parity sows. The average pig weaned weight and subsequent total pigs born improved as intake increased within parity. Prewean mortality decreased as feed intake increased within parity. These findings highlight the importance of ensuring sows are not only eating enough, but that they are consuming more than average when possible, to continually improve current and subsequent farrowing and litter performance. This study provides important information that will allow producers to target specific under-consuming sows and then promote consistent and high daily lactation intakes. Targeting these potentially nutrient-restricted sows may help reduce negative impacts on sow and litter performance.

The Prevalence of Depression Symptoms and Frequency of Risk Factors in Medical and Nursing Students: A Descriptive Cross-sectional Study.

OBJECTIVE: Currently, in Puerto Rico, there is a paucity of data regarding emotional health and depression in health professionals, specifically regarding trainees such as medical students and nursing students. The study intended to shed light on the prevalence of depression symptoms among medical and nursing students at a school of medicine in Puerto Rico. METHODS: In the fall of 2019, a descriptive cross-sectional study that included nursing and medical students in their first, second, and third years was performed. A survey consisting of the Patient Health Questionnaire (PHQ-9) and sociodemographic questions were used for data collection. Logistic regression analyses were used to determine the association of PHQ-9 scores and the risk factors linked to depression symptoms. RESULTS: A total of 173 (83.2%) out of 208 enrolled students participated in the study. Of the participants, 75.7% were medical students and 24.3% were nursing students. Of the risk factors studied, feelings of regret and lack of sleep were associated with a higher frequency of depression symptoms in medical students. For the nursing student population, suffering from a chronic disease was associated with a higher frequency of depression symptoms. CONCLUSION: Due to the increased risk of depression in healthcare professionals, identifying risk factors that can be addressed through early changes in behavior, or in institutional policies, is important in terms of working to mitigate the risk of mental health problems in this vulnerable population.

Integrin-linked kinase regulates cellular mechanics facilitating the motility in 3D extracellular matrices.

The motility of cells plays an important role for many processes such as wound healing and malignant progression of cancer. The efficiency of cell motility is affected by the microenvironment. The connection between the cell and its microenvironment is facilitated by cell-matrix adhesion receptors and upon their activation focal adhesion proteins such as integrin-linked kinase (ILK) are recruited to sites of focal adhesion formation. In particular, ILK connects cell-matrix receptors to the actomyosin cytoskeleton. However, ILK's role in cell mechanics regulating cellular motility in 3D collagen matrices is still not well understood. We suggest that ILK facilitates 3D motility by regulating cellular mechanical properties such as stiffness and force transmission. Thus, ILK wild-type and knock-out cells are analyzed for their ability to migrate on 2D substrates serving as control and in dense 3D extracellular matrices. Indeed, ILK wild-type cells migrated faster on 2D substrates and migrated more numerous and deeper in 3D matrices. Hence, we analyzed cellular deformability, Young's modulus (stiffness) and adhesion forces. We found that ILK wild-type cells are less deformable (stiffer) and produce higher cell-matrix adhesion forces compared to ILK knock-out cells. Finally, ILK is essential for providing cellular mechanical stiffness regulating 3D motility.