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Abstract: The ability of whey acidic protein fractions to protect against bone loss due to ovariectomy (OVX) in the mature female rat was investigated. The bone bioactivity of these acidic protein fractions, isolated from both mineral acid whey protein concentrate (WPC) and rennet WPC, was compared with that of basic protein fractions isolated from both milk and rennet WPC. Fifty 6-month old rats that had been ovariectomised at 5.5 months were randomised into five groups of ten each. One group remained the OVX control while four groups were each fed one of the acidic or basic protein fractions as 0.3% (w/w) of the diet, for 4 months. Ten sham-operated rats served as a second control group. Sequential measurements of bone mineral density of the spine and femur indicated that the acidic protein fraction prepared from mineral acid WPC reduced bone loss due to OVX, maintaining bone density above OVX levels at week 16 of feeding. Biomechanical data indicated that both acidic fractions tended to increase bone stiffness, and hence resistance against breaking. [Copyright &y& Elsevier]

Background: Multinutrient protein-enriched supplements are promoted to augment the effects of exercise on muscle mass and strength, but their effectiveness in middle-aged women, or whether there are any additional benefits to physical function, remains uncertain., Objectives: We aimed to evaluate whether a multinutrient-fortified milk drink (MFMD) could enhance the effects of exercise on functional muscle power (stair climbing) in middle-aged women. Secondary aims were to evaluate the intervention effects on physical function, muscle strength, lean mass (LM), fat mass (FM), bone mineral content (BMC), muscle cross-sectional area (CSA), muscle density, balance, flexibility, aerobic fitness, inflammation, oxidative stress, bone and cartilage turnover, blood pressure, and blood lipids., Methods: In this 4-mo, double-blind, placebo-controlled, randomized trial, 244 women (45-65 y) participated in a multimodal resistance-type exercise program 3 d/wk, with random allocation to a twice-daily MFMD containing added protein, vitamin D, calcium, milk fat globule membrane (phospholipids and other bioactives), and other micronutrients (Ex + MFMD, n = 123) or an energy-matched placebo (Ex + placebo, n = 121)., Results: A total of 216 women (89%) completed the study. After 4 mo, both groups experienced similar 3.6%-4.3% improvements in the primary outcomes of fast-pace 5- and 10-step stair ascent power. In contrast, Ex + MFMD experienced greater improvements in 5-step regular-pace stair descent time [net difference (95% CI): -0.09 s (-0.18, 0.00 s), P = 0.045], countermovement jump height [0.5 cm (0.04, 1.0 cm), P = 0.038], total body LM [0.3 kg (0.04, 0.60 kg), P = 0.020], FM [-0.6 kg (-1.0, -0.2 kg), P = 0.004], BMC [0.4% (0.1%, 0.6%), P = 0.020], muscle CSA [thigh: 1.8% (0.6%, 2.9%), P = 0.003; lower leg: 0.9% (0.3%, 1.6%), P = 0.005], balance eyes closed [3.3 s (1.1, 5.4 s), P = 0.005], 2-min step performance [8 steps (3, 12 steps), P = 0.003], and sit-and-reach flexibility [1.4 cm (0.6, 2.2 cm), P = 0.026]. MFMD did not enhance the effects of exercise on any measures of muscle strength, gait speed, dynamic balance, reaction time, or blood lipids, and there was no effect of either intervention on blood pressure, markers of inflammation, or cartilage turnover. Ex + placebo had a greater improvement in the oxidative stress marker protein carbonyls (P < 0.01)., Conclusions: In middle-aged women, daily consumption of an MFMD did not enhance the effects of a multimodal exercise program on the primary outcome of stair climbing ascent power, but did elicit greater improvements in multiple secondary outcomes including various other measures of functional performance, LM, muscle size, FM, balance, aerobic capacity, flexibility, and bone metabolism.This trial was registered at www.anzctr.org.au as ACTRN12617000383369., (Copyright © The Author(s) on behalf of the American Society for Nutrition 2020.)

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.

The acute and chronic effects of whey proteins on calcium metabolism and bone were evaluated. In acute studies, 8-week-old male rats were gavaged with 50 mg whey protein concentrate (WPC) and 25 mg calcium. 45Ca was administered intravenously or orally. Kinetic studies were performed, and femurs were harvested. Four of seven WPCs significantly increased femur uptake of 45Ca compared with controls. One WPC at 50 mg enhanced calcium absorption over a range of calcium intakes from 35.1 +/- 9.4% to 42.4 +/- 14.0% (P < 0.01). Three of the most effective WPCs were tested further in a chronic feeding study. One hundred 3-week-old rats were randomly divided into four adequate dietary calcium (ADC; 0.4% Ca) groups (control of 20% casein and three WPC groups with 1% substitution of casein with each of three WPCs) and two low calcium (LC; 0.2% Ca) groups (control of 20% casein and one WPC group with 1% substitution of casein with one WPC). After 8 weeks, there was no effect of WPCs on femur uptake of 45Ca among ADC groups and there was no effect of WPCs on calcium retention, femur breaking force, femur bone mineral density, or total femur calcium at either dietary calcium intake. However, whole body bone mineral content (BMC) was significantly higher (P < 0.05) in the three whey protein concentrate ADC groups compared with the ADC control group. Total BMC at the proximal tibia in whey protein ADC groups was increased, as shown by peripheral quantitative computed tomography. Our results indicate that the acute calcium absorption-enhancing effect of whey proteins did not persist through long-term feeding in rats. However, the initial enhancement of calcium absorption by whey protein was sufficient to increase BMC.

Three red deer calves (Cervus elaphus) died with a haemolytic disease associated with infection by Leptospira interrogans serovar pomona. Infection within the herd was more prevalent than disease. Sera from 16 herd mates were tested by the microscopic agglutination test (MAT) and 12 had leptospiral titres, the majority to serovar pomona. A few calves had titres to balcunica and hardjo. Urine was obtained for culture from six of these calves and serovar pomona was isolated from five with titres to pomona, and hardjo from one with a titre to hardjo but not pomona. A fourth calf died with severe nephritis but a diagnosis of leptospirosis was not confirmed in this case.

Subsequent to a cross-sectional serological survey of Manawatu dairy farm workers, a case-control study was carried out to investigate the correlation between titres to leptospiral serovars in workers and those in cattle in their herds. A total of 52 herds was investigated, 25 of which were high risk where milkers had titres of 1:96 or greater, and 27 were case-controls where milkers had no detectable agglutinin titres at a minimum serum dilution of 1:24. The serological prevalence of titres to hardjo in cattle on high risk farms (76.5%) was significantly higher (P<0.05) than on the case-control farms (60.0%). The geometric mean titres of seropositive cattle on high risk farms were also significantly higher (P<0.01) than in the cattle from the case-control farms, especially in the younger cohorts. These findings suggest that there was active endemic hardjo infection in the two- to three-year-old cattle on the high risk farms. Titres to pomona were demonstrated in only 5.2% of the cattle from both types of farm. Workers with titres to pomona tended to be from farms on which stock, especially calves, were bought-in and pigs were kept. Conventional measures for protecting milkers from contact with infected urine appeared to be ineffective and it is concluded that prevention of leptospirosis in dairy farm workers can only be achieved by elimination of infection in the herd by vaccination of cattle.

The sera of 460 people associated with farming were examined for evidence of leptospiral agglutinins. Of these, 308 were dairy farm workers, 62 percent of whom were from the Waikato. Forty-four percent of dairy farm workers, 8 percent of sheep and beef farmers and 25 percent of pig farmers ware seropositive. Of the 137 seropositive dairy farm workers, 65 percent had titres to serovar hardjo and 53 percent to pomona. There were no significant differences between the serological prevalences of workers in different geographical regions. Analysis of factors significantly associated with seropositive workers included; being male, a previous history of medically confirmed leptospirosis in the worker, a clinical history of leptospirosis in the cattle, the size of the milking herd, the type of milking shed, and vaccination of the herd against leptospirosis. These findings indicate that the incidence of leptospirosis in dairy farm workers can only be effectively controlled by reducing the prevalence of infection in dairy cattle.

The sera from 1215 meat inspectors and 1248 meat workers were examined for the presence of agglutinating titres of 1:24 or greater to the serovars of Leptospira interrogans known to be endemic in New Zealand. Although 10 percent of meat inspectors and 6.2 percent of meat workers were seropositive, only 9.5 percent of meat inspectors and 4.1 percent of meat workers had titres compatible with occupational exposure to domestic stock. The subgroup of meat workers with the highest prevalence of agglutinins (10.4 percent) were those working on the slaughter floor, and the inspection and processing of pigs were shown to be the most important risk factors. More than 50 percent of those with a history of medically confirmed leptospirosis in the past ten years still had detectable titres. Although the results of this survey demonstrate that leptospirosis is a definite occupational hazard in the meat industry, the risk is threefold less than for dairy farm workers and pig farmers.

Six adult, female, red deer were vaccinated with a hardjo-pomona vaccine followed by a second vaccination four weeks later and thereafter, at yearly intervals for two years. Serological responses were determined at intervals using a standard microscopic agglutination test. Increased responses to hardjo were observed in two deer which were seropositive to this serovar before vaccination compared to those which were initially seronegative. Some initially seronegative deer developed titres to hardjo and pomona ranging from 1:24 to 1:48 following the first dose of vaccine, and all deer produced a serological response to both serovars ranging from 124 to 1:96 following the second vaccination except one animal which failed to produce a pomona titre of 124 or greater. Responses to annual revaccinations were more variable both within and between years. Most deer produced titres which ranged from 1:24 to 1:96 for three to live months, although some deer failed to seroconvert following the annual revaccinations. Peak responses were similar to those recorded in cattle following an identical vaccination programme with the same vaccine but titres fell to undetectable levels after three to live months whereas titres reported in cattle generally persisted for at least 12 months.

Serum samples were examined from 70 people working or resident on 41 pig farms within a 50 km radius of Palmerston North. Of the 65 people with occupational pig contact, 20 (31 percent) had microscopic agglutination titres of 1:24 or greater to one or more serovars of Leptospira interrogans, the majority of which were to pomona, the pid adapted serovar. There were significant positive associations between those people with a titre and those with a history of previous diagnosis of leptospirosis by a medical practitioner and the number of breeding sows and fattening pigs on the property. Pig farmers are at similar risk to contracting leptospirosis as dairy farmers, but the major serovars involved are different, and the total population at risk is less. Further evidence is provided that titres to leptospiral agglutinins can persist in humans for longer than ten years.

Sixty-nine meat inspectors with titres of leptospiral agglutinins ranging from 1:768 to 1:24, were re-bled and reexamined periodically over a period of 53 months. Some individuals maintained titres of 1:384 and 1:192 for at least 30 months and others with initial titres of 1:48 and 1:24 maintained such titres for 53 months. Only six, of 63 initially seronegative (less than 1:24) meat inspectors, seroconverted during the period of study. The magnitudes of titres at a single sampling from each of 162 people, with previous histories of medically confirmed leptospirosis, were analysed in relation to time elapsed since initial diagnosis. Some individuals had titres of 1:192 seven years after infection, while others had lower titres after more than 20 years. Conversely, 12% of the population was seronegative two years after infection. These results indicate that it is not possible, from the results of a leptospiral agglutination test, to estimate retrospectively the time at which infection may have occurred. In a small proportion of individuals recently affected by leptospirosis, it will not be possible to demonstrate a change in agglutinating titre.

Four red deer calves (Cervus elaphus) died with severe nephritis apparently associated with infection by Leptospira interrogans serovar pomona. The sera of 12 in-contact red deer calves were examined for leptospiral agglutinins and nine showed titres to pomona consistent with recent infection. Two also showed titres of 1:100 to serovar hardjo. The urine of five of these in-contact calves was examined periodically over a period of nine months. All were initially leptospiruric, four being infected with pomona and one with hardjo. In four animals leptospiruria could only be detected for up to six months, but one animal infected with pomona was leptospiruric for at least eight months. The apparent source of infection was from infected cattle, and it is suggested that deer are unlikely to act as maintenance hosts for serovar pomona.

A commercial hardjo-pomona vaccine which has previously been shown to be effective against hardjo infection was tested against pomona. Following challenge all 11 six-month-old non-vaccinated calves seroconverted and pomona was isolated from blood or urine on at least one occasion from nine of them. Pomona was isolated once only, on the third day after challenge, from the blood of one of 11 vaccinated calves.

A serological survey of leptospirosis among more than 1000 meat inspectors, from meat works throughout New Zealand, revealed a serological prevalence at a minimum serum dilution of 1:24, of 10.2 percent. Eighty-five percent of serological reactions were to serovars pomona and tarassovi. A highly significant correlation was demonstrated between the serological prevalence of these serovars and the inspection of pigs. Evidence is provided to substantiate the use of titres as low as 1:24 as an indication of previous leptospiral infection. Forty-two inspectors reported medical evidence of previous clinical infection with leptospirosis. Analysis of those who still exhibited a serological response and their individual case histories, indicated that detectable titres of leptospirosis can exist for up to 10 years.

The serological responses of calves at two different ages to a commercial hardjo/pomona vaccine were examined. Microscopic agglutination test (MAT) titres of a group of ten three-month-old calves and three groups of 11,12 and 12 six-month-old calves were monitored over a period of 28 weeks. The calves vaccinated at three months of age had a poorer serological response rate to vaccination (30% responded to pomona and 40% responded to hardjo) compared with those vaccinated at six months of age (91-100% responded to pomona and 83-91% responded to hardjo). Those three-month-old calves which did respond also produced a lower level of-antibody than six-month-old calves. It was concluded that in order to achieve adequate protection using commercially available leptospiral bacterins at the recommended dose, vaccination should not be undertaken routinely with animals less than six months of age. Where circumstances arise in which earlier vaccination is necessary, repeat vaccination for continued protection at six months or older is suggested.