Dairy cows’ motivation to nurse their calves

\ua9 The Author(s) 2024. When weaning offspring, female mammals limit nursing opportunities. This study aimed to investigate whether imposing a gradual reduction in daily contact time, by separating cows from their calves as an attempt to stimulate weaning, reduced dairy cows’ motivation to nurse their calves. For seven weeks, 84 Holstein–Friesian cow-calf pairs were housed with either full-time (23 h contact/d), part-time (10 h contact/d), or no contact. In the following two weeks, half of full- and part-time pairs were subjected to reduced contact (50% of initial contact in week 8, 25% of initial contact in week 9), while the other half continued with unchanged contact. In weeks 8 and 9, cows’ motivation to obtain full contact to and opportunity to nurse their calves was measured using weighted push gates using a novel maximum price paid method providing an alternative choice to the cows to reduce frustration. Cows with reduced calf contact were more motivated than cows with unchanged contact; however, cows used the alternative choice less than expected. The results show that cows’ motivation for full calf contact and opportunity to nurse increases when daily calf contact is reduced, illustrating that dairy cows are motivated to continue nursing their 9- to 10-week-old calves

Dairy cows housed both full- and part-time with their calves form strong maternal bonds

\ua9 2024 The Authors. Dairy cow and calf are typically separated shortly after calving preventing the formation of a maternal-filial bond. To allow some cow-calf contact, part-time contact during the first weeks is thought to be a feasible solution, but it is unknown if it weakens maternal bond, i.e., if maternal motivation is lower. This study aimed to investigate how different amounts of calf contact (full-time, part-time, and no contact) affect cows’ maternal motivation. Using pneumatic push gates, we assessed cows’ motivation to access their own calf using the maximum price paid (MPP) method. To mitigate frustration at high prices, cows could also access an unfamiliar calf at a constant low price. We expected that cows would access the unfamiliar calf when reaching the maximum price that they were motivated to pay to access their own calf. Following 48 h in a calving pen, cow-calf pairs were allocated to three different treatments: full-time (23 h contact/d, 28 pairs), part-time (10 h contact/d, 27 pairs), and no contact (0 h contact/d, 26 pairs). Approximately 40 d after calving, cows were trained to pass through each of two push gates: one leading to their own and one leading to an unfamiliar calf. The weight on the gate leading to the cows’ own calf increased following each passing, while the gate leading to the unfamiliar calf remained light. Cows were tested once daily, until they failed to pass through the gate leading to their own calf on two consecutive days. MPP was analysed using a Cox\u27s proportional hazards mixed effects model. Fewer no-contact cows than full- and part-time cows fulfilled the learning criteria. Furthermore, no-contact cows paid a lower maximum price compared to the two contact treatments, while the MPP of full- and part-time cows did not differ. Most cows remained in the start box if they did not pass the gate to their own calf, indicating that an unfamiliar calf could not substitute for their own calf at high prices. We conclude that cows with part-time calf contact form a maternal bond of similar strength to cows with full-time calf contact. Additionally, cows separated from their calf at 48 h after calving have a weaker maternal motivation at 40 days postpartum

Pregnancy postponement and childlessness leads to chronic hypervascularity of the breasts and cancer risk

Epidemiologists have established that women with small families, and particularly nulliparae, are prone to develop breast cancer later in life. We report that physiological mammary hypervascularity may be an intermediate reason against the background that breast-core vascularity is normal in pregnancy but pathological in the vascularisation of cancer. We examined breast ‘core’ vascularity in nulliparae during their potential reproductive life and in parous women after their last birth but before their menopause. Fifty clinically normal pre-menopausal non-pregnant women (100 breasts) were studied daily for one ‘luteal positive’ menstrual cycle. Their parity history varied from zero to five babies. Under controlled domestic conditions each wore a special electronic thermometric bra to automatically record breast ‘core’ temperature changes as a measure of mammary tissue blood flow. In the nulliparae there was a rise of breast vascularity throughout reproductive life. In the parous women, a year or so after each birth, breast vascularity was reset at a lower level than before the pregnancy; thereafter, as in nulliparae, there was progressive increase in mammary vascularity until the menopause

How heel oxygenation changes under pressure

The mechanism of heel pressure ulcers after hip surgery is not entirely understood. The purpose of this one-group, prospective, repeated-measures design study was to examine how the external pressure of the bed surface affects heel skin oxygen tension in adults on the first 3 days after hip surgery. Transcutaneous oxygen sensors were placed on the plantar surface of each foot, close to the heels. Measures were taken on room air and with an oxygen challenge with the heels (1) suspended above the bed surface (preload), (2) on the bed surface for 15 minutes (loading), and (3) again suspended above the bed surface for 15 minutes (unloading). Eighteen hip surgery patients (mean age 58.3±16.1 years) from two hospitals participated. When compared with preload on room air, both loading and unloading on all 3 days resulted in a reduction in heel oxygen tension bilaterally (p\u3c0.001). Heel oxygenation decreased without the anticipated hyperemic response, raising the question of whether this is a sign of increased pressure ulcer risk. Further work is needed to understand why this short period of external pressure results in decreased oxygenation and why oxygen tension does not return to baseline when pressure is removed

Evolutionary dynamic optimisation of airport security lane schedules

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Reducing costs whilst maintaining passenger satisfaction is an important problem for airports. One area this can be applied is the security lane checks at the airport. However, reducing costs through reducing lane openings typically increases queue length and hence passenger dissatisfaction. This paper demonstrates that evolutionary methods can be used to optimise airport security lane schedules such that passenger dissatisfaction and staffing costs can be minimised. However, it is shown that these schedules typically over-fit the forecasts of passenger arrivals at security such that in actuality significant passenger delays can occur with deviations from the forecast. Consequently, this paper further demonstrates that dynamic evolutionary re-optimisation of these schedules can significantly mitigate this over-fitting problem with much reduced passenger delays

The spectra of lifted digraphs

We present a method to derive the complete spectrum of the lift \mathrm{\Gamma\alpha} of a base digraph \mathrm{\Gamma}, with voltage assignment α on a (finite) group $\textit{G}$. The method is based on assigning to \mathrm{\Gamma} a quotient-like matrix whose entries are elements of the group algebra \mathds{C}[$\textit{G}$], which fully represents \mathrm{\Gamma\alpha}. This allows us to derive the eigenvectors and eigenvalues of the lift in terms of those of the base digraph and the irreducible characters of G. Thus, our main theorem generalizes some previous results of Lovász and Babai concerning the spectra of Cayley digraphs

Iron chelation therapy in the myelodysplastic syndromes and aplastic anemia: a review of experience in South Korea

Emerging clinical data indicate that transfusion-dependent patients with bone marrow-failure syndromes (BMFS) are at risk of the consequences of iron overload, including progressive damage to hepatic, endocrine, and cardiac organs. Despite the availability of deferoxamine (DFO) in Korea since 1998, data from patients with myelodysplastic syndromes, aplastic anemia, and other BMFS show significant iron overload and damage to the heart and liver. The recent introduction of deferasirox, a once-daily, oral iron chelator, may improve the availability of iron chelation therapy to iron-overloaded patients, and improve compliance in patients who may otherwise find adherence to the DFO regimen difficult