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Context. Variations in the number of milkings each day and their timing are becoming increasingly common. How these changes affect cow behaviour is poorly understood. When cows are milked less frequently, their walking to and from the dairy is reduced and their amount of time spent at pasture increases; however, the impact on activity under different milking schedules has not been measured. Aims. The objective of this study was to identify any differences in cow walking activity (steps per hour) among three milking frequencies and three milking schedules of 3-in-2 (milking three times in 2 days), at two stages of lactation (34 and 136 days in milk), over a period of 6 weeks. Time spent eating was assessed to help explain differences in activity within a day. Methods. Data were collected from five groups of 40 cows (n = 200) milked, as follows: once a day (OAD); twice a day (TAD); 3-in-2 (three groups) at intervals of 12-18-18 h, 10-19-19 h, and 8-20-20 h. All cows were fitted with AfiAct pedometers, which recorded steps per hour. Eight cows in each treatment group were also fitted with CowManager SensOor™ ear tags, which recorded minutes per hour spent eating. Key results. Cow steps per hour increased with an increasing milking frequency in both trial periods. When data associated with walking to and from milking were removed, there were still differences in cow step activity. Cows milked OAD took 30% fewer steps than TAD cows. The diurnal pattern of eating time differed between these two trial groups. The effect of milking time among the 3-in-2 trials showed that the shorter the time between the milkings on the day the cows were milked twice, the greater the number of steps per hour. There were graphical eating differences between the 8-20-20 trial group and 12-18-18 trial group on the day that cows were milked twice. Conclusions. We conclude that both the number and timings of milkings affect a cow's step activity and grazing behaviour. Implications. Farmers should minimise the amount of time cows spend away from the paddock, especially in the afternoon, to minimise any changes to natural behaviour. [ABSTRACT FROM AUTHOR]

Robust information for water use on pasture-based dairy farms is critical to farmers' attempts to use water more efficiently and the improved allocation of freshwater resources to dairy farmers. To quantify the water requirements of dairy farms across regions in a practicable manner, it will be necessary to develop predictive models. The objectives of this study were to compare water use on a group of irrigated and nonirrigated farms, validate existing water use models using the data measured on the group of nonirrigated farms, and modify the model so that it can be used to predict water use on irrigated dairy farms. Water use data were collected on a group of irrigated dairy farms located in the Canterbury, New Zealand, region with the largest area under irrigation. The nonirrigated farms were located in the Manawatu region. The amount of water used for irrigation was almost 52-fold greater than the amount of all other forms of water use combined. There were large differences in measured milking parlor water use, stock drinking water, and leakage rates between the irrigated and nonirrigated farms. As expected, stock drinking water was lower on irrigated dairy farms. Irrigation lowers the dry matter percentage of pasture, ensuring that the amount of water ingested from pasture remains high throughout the year, thereby reducing the demand for drinking water. Leakage rates were different between the 2 groups of farms; 47% of stock drinking water was lost as leakage on nonirrigated farms, whereas leakage on the irrigated farms equated to only 13% of stock drinking water. These differences in leakage were thought to be related to regional differences rather than differences in irrigated versus nonirrigated farms. Existing models developed to predict milking parlor, corrected stock drinking water, and total water use on nonirrigated pasture-based dairy farms in a previous related study were tested on the data measured in the present research. As expected, these models performed well for nonirrigated dairy farms but provided poor predictive power for irrigated farms. Partial least squares regression models were developed specifically to simulate corrected stock drinking water, milking parlor water, and total water use on irrigated dairy farms. [ABSTRACT FROM AUTHOR]

• Behaviour of metabolically challenged grazing dairy cows was investigated. • Metabolically challenged cows lay less and walked more before calving. • Cows experiencing a metabolic challenge were also less active postcalving. • Cows divergent in metabolic status have different behaviour patterns to healthy cows. • Monitoring behaviour may allow metabolically challenged cows to be identified. During early lactation, most dairy cows experience negative energy balance (NEB). Failure to cope with this NEB, however, can place cows at greater risk of developing metabolic disease. Our objective was to characterise, retrospectively, lying behaviour and activity of grazing dairy cows grouped according to blood non-esterified fatty acids (NEFAs) and β-hydroxybutyrate (BHB) as indicators of postpartum metabolic state. Blood was sampled weekly for up to 4 weeks precalving, on the day of calving (day 0), daily between 1 and 4 days postcalving, and then at least weekly between week 1 and week 5 postcalving for analysis of plasma NEFAs and BHB concentrations. Two hundred and forty-four multiparous Holstein-Friesian and Holstein-Friesian × Jersey cows were classified into one of three metabolic status groups based on maximum blood NEFAs and BHB concentrations during week 1 and 2 postcalving. A cow was classified as having either: (1) low NEFAs and low BHB (Lo–Lo ; n = 78), when all blood samples were <1.0 mmol/L for NEFAs and ≤1.0 mmol/L for BHB during the first 2 weeks postcalving; (2) high NEFAs and low BHB (Hi–Lo ; n = 134), when blood NEFAs were ≥1.0 mmol/L and blood BHB was ≤1.0 mmol/L at the same sampling time point during the first 2 weeks postcalving; or (3) high NEFAs and high BHB (Hi–Hi ; n = 32), when blood NEFAs were ≥1.0 mmol/L and blood BHB was ≥1.2 mmol/L at the same sampling time point during the first 2 weeks postcalving. Accelerometers (IceTag or IceQube devices; IceRobotics Ltd.) were used to monitor lying and activity behaviours peripartum (–21 to +35 days relative to calving). Changes in lying behaviour and activity occurred before the mean day that cows were classified Hi–Hi and Hi–Lo (2.2 and 3.5 d postcalving, respectively). Up to 3 weeks preceding calving, Hi–Hi cows were more active, had fewer daily lying bouts (LB s), and spent less time lying than Lo–Lo cows. In addition, Hi–Hi cows had fewer daily LBs and were less active up to 4 weeks postcalving than Lo–Lo cows, but these differences were biologically small. Groups of grazing cows classified as experiencing a more severe metabolic challenge behave differently up to 3 weeks precalving than their herdmates with lower blood NEFAs and BHB postcalving. These altered behaviours may allow identification of individual cows at risk of a metabolic challenge, but further research is required. [ABSTRACT FROM AUTHOR]

Failure of perennial ryegrass‐based pastures to persist beyond 3 years post‐sowing is an increasing threat to the sustainability of livestock industries in the north of New Zealand. Little is known of the long‐term responses of plants and populations to the environmental stresses responsible for persistence failure, or the effects of ryegrass genetics on those responses. Plants were collected from 10‐year‐old pastures sown in two environments (Waikato, North Island: warm‐temperate, summer/autumn dry; Canterbury, South Island: cool temperate, irrigated) to four ryegrass functional types and grazed by dairy cattle. Surviving plants in Canterbury pastures were almost all true‐to‐type for the original genotype, whereas there was substantial ingress of volunteer plants in the diploid cultivars in Waikato. Plants confirmed as true‐to‐type were compared to reference plants grown from the original seed lines. Leaf mass was lower in survivor plants than in reference plants for all functional types. This effect was reversed by recruitment of new plants from seed in a grazing deferment treatment applied at the Waikato site 18 months before plant collection, in a manner consistent with epigenetic control. Reproductive development was delayed by 4–6 days in survivors of mid‐ and late flowering diploid cultivars: this effect appeared to be the result of true genetic differentiation. There was less aftermath heading in the Canterbury survivors, but not Waikato survivors, compared with the reference plants. The relevance of these findings for ryegrass survival strategies and targeted selection of traits for improved persistence is discussed. [ABSTRACT FROM AUTHOR]

Reverse-transcription quantitative-PCR (RT-qPCR) is commonly used for assessing the cellular response to changes in physiologic and pathologic conditions. The selection of stable endogenous control genes is an important step of any RT-qPCR study, as expression can vary depending on the experimental environment. Our objective was to identify endogenous control genes in circulating neutrophils isolated from cows during the peripartum period. To do this, we used microfluidics gene expression arrays (Fluidigm, San Francisco, CA) for RT-qPCR analysis. Selection of the endogenous control genes was based on previous research investigating gene expression in neutrophils. The selected genes included ACTB, B2M, G6PD, GAPDH, GCH1, GOLGA5, OSBPL2, PGK1, RPL13A, RPL19, RPS9, SDHA, SMUG1, SNRPA, TBP, UXT, and YWHAZ. Four genes (GAPDH, GOLGA5, PGK1, and UXT) did not provide satisfactory quantification results using the selected method and were therefore excluded from the analyses. The suitability of the remaining 13 genes for use as endogenous control genes was assessed using geNorm and Normfinder. The gene pair with the greatest stability using geNorm was RPL13A and RPL19, whereas Normfinder ranked RPL19 and YWHAZ as the most stable pair. The 2 genes deemed most suitable for the experimental design were RPL19 and YWHAZ, which were selected for subsequent gene expression analysis. This study highlights that genes used as endogenous controls for relative quantification should be assessed on an experimental basis, even if the genes have been used in previous research. [ABSTRACT FROM AUTHOR]

This observational study determined the effect of genetic merit for fertility traits on estrous activity and duration and inter-estrous interval in nulliparous dairy heifers. We also compared estrous activity between estrous events with or without conception and determined the effect of genetic merit for fertility traits on age and body weight at time of first detected estrous activity event. Activity monitoring devices (Heatime, SCR Engineers) were fitted to 7-9-mo aged Holstein-Friesian heifers with positive or negative genetic merit for fertility traits (POS FertBV: average +5%, n = 275; NEG FertBV: average -5%, n = 249) and activity data was collected to the end of the first breeding period (15-17-mo). An estrous event was defined as when the activity change index exceeded 19.2 activity units (AU) for ≥6 consecutive h. In total, 2,434 estrous events were identified (POS FertBV: n = 1454; NEG FertBV: n = 980). Estrous event duration was defined as the period when the threshold was first exceeded and when activity dropped below threshold, without another event starting within 24 h of the end of the previous event. This definition included occurrences where activity crossed the threshold multiple times in a day; these were classified as a single estrous event. A second measure, high activity duration, was defined as the total time activity exceeded the threshold. To characterize estrous activity, baseline activity was determined from the previous 7 d of activity. Peak activity and total activity (area under the curve of activity above baseline) were calculated. A fifth variable, inter-estrous interval, was calculated as a proxy for estrous cycle length. Total activity and peak activity were greater in POS than NEG FertBV heifers (total activity: 548 vs 464 AU, SED = 19.6 AU; peak activity: 72 vs 65 AU, standard error of the difference (SED) = 1.5 AU). The POS FertBV group had a mean estrous event duration and high activity duration of 15.1 h and 15.0 h, compared with 14.1 and 14.1 h for the NEG FertBV group (SED = 0.30 and 0.29 h, respectively). Inter-estrous interval did not differ between POS and NEG FertBV heifers (19.5 vs 20.0 d, SED = 0.49). Estrous events associated with conception were shorter than those not associated with conception (mean ± standard error of the mean, high activity duration: 13.0 ± 0.25 h vs 13.9 ± 0.31 h, estrous event duration: 13.1 ± 0.25 h vs 14 ± 0.32 h) and had less total activity (408 ± 15.2 vs 487 ± 18.2 AU). The POS FertBV heifers were more likely to have their first estrous activity event than NEG FertBV heifers by a given age (HR = 1.26, 95% CI = 1.0 to 1.6) or body weight (HR = 1.35, 95% CI = 1.1 to 1.6). The outcomes of this study provide evidence that positive genetic merit for fertility traits is associated with more overt estrous expression. Therefore, estrous expression traits may have potential to be used as earlier-in-life predictors of genetic merit for fertility., (© 2024, The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

The benefits of sufficient and high-quality sleep for people are well documented. Insufficient sleep increases the risk of accidents, injuries, and negative health implications for people. This is especially relevant for farmers, as they work with large animals and machinery. Dairy farming often requires early start times and long days, particularly over the high workload calving period in block calving, pasture-based systems. However, there is little published data quantifying the sleep quantity and quality of farmers over this period. In this study, the sleep patterns of workers (n = 33) on 10 New Zealand dairy farms was measured for 90 d over the spring calving period using a sleep measuring device (Oura TM ring, Oura Health Ltd., Oulu, Finland). Total sleep time (TST) averaged 6 h 15 min, lower than the required 7 to 9 h for optimal wellbeing and cognitive functioning. TST decreased over the calving period and was significantly correlated with both sleep start and wake times. Factors such as work start time, farm location, and role on farm influenced sleep quantity and quality; indicating adjusting these on-farm factors could positively impact TST. Further research is required to better understand sleep and its effect on dairy farmers, over both the calving period and the remaining months of the year., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

Introduction: Consumption of green kiwifruit is known to relieve constipation. Previous studies have also reported improvements in gastrointestinal (GI) comfort. We investigated the effect of consuming green kiwifruit on GI function and comfort., Methods: Participants included healthy controls (n = 63), patients with functional constipation (FC, n = 60), and patients with constipation-predominant irritable bowel syndrome (IBS-C, n = 61) randomly assigned to consume 2 green kiwifruits or psyllium (7.5 g) per day for 4 weeks, followed by a 4-week washout, and then the other treatment for 4 weeks. The primary outcome was the number of complete spontaneous bowel movements (CSBM) per week. Secondary outcomes included GI comfort which was measured using the GI symptom rating scale, a validated instrument. Data (intent-to-treat) were analyzed as difference from baseline using repeated measures analysis of variance suitable for AB/BA crossover design., Results: Consumption of green kiwifruit was associated with a clinically relevant increase of ≥ 1.5 CSBM per week (FC; 1.53, P < 0.0001, IBS-C; 1.73, P = 0.0003) and significantly improved measures of GI comfort (GI symptom rating scale total score) in constipated participants (FC, P < 0.0001; IBS-C, P < 0.0001). No significant adverse events were observed., Discussion: This study provides original evidence that the consumption of a fresh whole fruit has demonstrated clinically relevant increases in CSBM and improved measures of GI comfort in constipated populations. Green kiwifruits are a suitable dietary treatment for relief of constipation and associated GI comfort., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)

Background: Cytokines, chemokines, C-reactive proteins (CRP) and ferritin are known inflammatory markers. However, cytokines such as interleukin (IL-1β), (IL-6) and tumour necrosis factor (TNF-α) have been reported to interfere with both the bone resorption and bone formation processes. Similarly, immune cell cytokines are known to contribute to inflammation of the adipose tissue especially with obesity. IL-10 but not IL-33 has been linked to lower ferritin levels and anemia. In this study, we hypothesized that specific cytokine levels in the plasma of women with low bone mineral density (BMD) would be higher than those in the plasma of healthy women due to the actions of elevated levels of pro-inflammatory cytokines in inducing osteoclast formation and differentiation during senescence., Results: Levels of cytokines (IFNα2, IFN-γ, IL-12p70, IL-33) and monocyte chemoattractant protein-1 (MCP-1) were significantly higher in the plasma of the osteoporotic group compared to the osteopenic and/or healthy groups. Meanwhile CRP levels were significantly lower in women with osteoporosis ( P  = 0.040) than the osteopenic and healthy groups. Hip BMD values were significantly lower in women with high/detectable values of IL-1β ( P  = 0.020) and IL-6 ( P  = 0.030) compared to women where these were not detected. Similarly, women with high/detectable values of IL-1β had significantly lower spine BMD than those where IL-1β was not detected ( P  = 0.030). Participants' CRP levels were significantly positively correlated with BMI, fat mass and fat percentage ( P  < 0.001). In addition, ferritin levels of women with high/detectable values of anti-osteoclastogenic IL-10 ( P  = 0.012) and IL-33 ( P  = 0.017) were significantly lower than those where these were not detected. There was no statistically significant association between TNF-α and BMD of the hip and lumbar spine., Conclusions: High levels of cytokines (IFNα2, IFN-γ, IL-12p70, IL-33) and MCP-1 in apparently healthy postmenopausal women are associated with bone health issues. In addition, an increase in levels of IL-10 and IL-33 may be associated with low ferritin levels in this age group., Trial Registration: ANZCTR, ACTRN12617000802303. Registered May 31st, 2017, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373020., Competing Interests: Competing interestsThe authors declare that they have no competing interests.

This study compared the effects of a high-calcium vitamin D fortified milk with added FOS-Inulin versus regular milk on serum parathyroid hormone (PTH), vitamin D status, grip strength (GS), as well as bone density in Chinese premenopausal women over 52 weeks. Premenopausal women ( n  = 133), mean age 41 (±5.1) years were randomized into control ( n  = 66; regular milk at 500 mg calcium per day) or intervention (Int; n  = 67; fortified milk at 1200 mg calcium, 15 μg vitamin D, and 4 g FOS-Inulin per day) groups. Assessments were at baseline, weeks 12, 24, 36, and 52 for changes in vitamin D status, levels of PTH, and GS. Bone mineral densities (BMDs) of the lumbar spine (LS), femoral neck (FN), and whole body (WB) were assessed at baseline and week 52 using GE Lunar iDEXA (GE Healthcare, Madison, WI). At baseline, WB lean mass was positively associated with LS BMD ( r  = 0.30, p  < 0.001) and FN BMD ( r  = 0.33, p  = 0.003). Baseline 25(OH) vitamin D3 levels were 48.6 and 53.2 nmol/L ( p  = 0.57), respectively, and after the 12 months at 60.8 nmol/L (Int) versus 55.0 nmol/L (controls; p  < 0.05 for change from baseline for both groups; no difference between groups at week 52). PTH levels decreased in both groups compared to baseline ( p  < 0.001), with no significant difference between groups. WB bone mineral content (BMC) and FN Z-score increased significantly in the Int group ( p  = 0.024 and p  = 0.008). GS was positively associated with body weight, increasing in both groups over 52 weeks. Fortified milk improved vitamin D status, WB BMC, and Z-score of the FN, while regular milk maintained BMD. In addition, vitamin D status and GS improved., Competing Interests: All authors declare that no competing financial interest exists.