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The trade-offs when altering milking frequency and timing for pastoral, block-calving dairy farms : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
Get PDFThe purpose of this thesis was to quantify the effect of milking frequency and intervals on elements of the farm system, which included milk production, cow behaviour and farmer’s sleep. Dairy farmers face challenges attracting and retaining staff, partly due to the difficulty meeting the desires of the modern workforce which include flexible work hours and regular time off. The task of milking fundamentally impacts the ability of dairy farms to meet these desires. Milking contributes to a large proportion of the hours spent working on dairy farms. The number of milkings (milking frequency) and their timing (milking interval) within a day influence the number of hours spent milking and at what time in the day they occur. Milking 3 times in 2 days (3-in-2) reduces the amount of time spent milking compared to milking twice a day (TAD), without reducing milk yield as much as milking once a day (OAD). However, there are a variety of ways these milkings can be arranged within the 2 days, resulting in a variety of 3-in-2 milking intervals that have had little to no exploration.
To determine the effect of milking interval within a 3-in-2 milking frequency on milk yield and composition at 2 stages of lactation and compare these with OAD and TAD milking, study 1 milked 5 herds of 40 cows at 5 different milking intervals at early (34 days in milk) and mid (136 days in milk) lactation. The milking treatments included once a day (OAD), 3 variations of 3-in-2 milking: an 8-20-20 hour, 10-19-19 hour and 12-18-18 hour interval, and TAD with a 10-14 hour interval. When comparing 3-in-2 milking intervals, a small numerical but statistically insignificant difference was observed in milk and component yields, through both stages of lactation. Consequently, the results of this study suggest that farmers using 3-in-2 could choose a shorter milking interval on the day with 2 milkings. Or alternatively, farmers have the flexibility to select a milking interval that suits best their requirements without significantly compromising milk yield. In agreeance with previous literature, decreasing milking frequency was associated with decreasing protein, lactose and milk yield. At mid-lactation there was no significant difference between TAD and the 12-18-18 interval of 3-in-2 for milk and component yields, providing an opportunity for farmers to decrease the number of milkings by 25% in later lactation without compromising milk production, when it’s past peak.
The effect of milking interval and milking frequency on milk production is not the only factor that will influence a farmer’s decision to alter their milking schedule. 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, how this impacts behaviour has had very little investigation. To explore the effect of milking frequency on cow behaviour, in study 2, an exploration of an existing dataset showed that there were changes in cow behaviour when milking frequency changed. CowManager tags, which provide minutes per hour in one of five behaviour categories (active, not active, high active, ruminating, and eating) were attached to cows (n=29) transitioning from a twice a day (TAD) to a 3-in-2 milking schedule at mid-lactation (85 days in milk). When transitioned to 3-in-2 milking, activity significantly increased (+32.3 mins/cow/day; P<0.05), despite less walking to and from milking. When cows were milked 3-in-2, eating time was less (-1.99 mins/hour/cow) during daylight hours and greater during dark hours (+1.57 mins/hour/cow) when compared with when they were on the TAD milking schedule. Ruminating time was not different during daylight but was less during dark hours (-1.64 mins/hour/cow) when cows were milked 3-in-2. These findings indicated that in mid lactation, reducing milking frequency provided cows with more time for social interaction and/or feed searching behaviours, as evidenced by their increase in activity. It also indicates that the timing of milking may influence diurnal behaviour patterns.
This study was limited by the short period of observation, and lack of comparative treatments, so a third study was conducted for a more in-depth analysis of milking interval on animal behaviour. Cows from study 1 had AfiAct pedometers attached, which measured steps per hour, and a cohort of 8 cows per treatment had the aforementioned CowManager tags attached as well. Cows that were milked OAD had the lowest activity in the paddock, 86 and 133 steps cow/hour less than 3-in-2 groups at early and mid-lactation respectively, and 65 and 135 steps cow/hour less than the TAD group. Cows milked 3-in-2 were also less active in the paddock on the day they were milked once (approximately 40 steps less per hour at early lactation, and 80 less at mid lactation). However, cows that were milked 3-in-2 were more active than TAD cows in early lactation, similar to what was observed in study 2, although this result was not consistent at mid-lactation. When milking was later in the afternoon, the timing of grazing became later. This was observed when comparing the 12-18-18 3-in-2 group milked at 5PM, in comparison to the 8-20-20 3-in-2 group milked at 2PM. Therefore, altering milking frequency and timing will result in cow behaviour change.
Finally in study four, to determine whether milking frequency effects farmer’s behaviour, farmers milking either OAD (n=11) or TAD (n=22) in the South Island of New Zealand wore a sleep measuring device (OuraTM ring) for 90 days over the spring calving period. Neither OAD or TAD farmers were getting sufficient sleep over the calving period (6.3 hours compared to the recommended 7-9 hours). Furthermore, there were no significant differences in sleep quality or quantity between people working on farms milking OAD and TAD. However, this study was limited by the amount the rings were worn by the study participants, and the number of farms involved. Wake time, connected to milking time, was correlated with total sleep time. When milking time became earlier as calving progressed and more cows were needing to be milked, total sleep time decreased. This study demonstrated that there were factors other than milking frequency, such as milking time, farm management, weather and role on farm that were more influential on sleep quantity and quality.
Overall, milking frequency and timing was shown to affect milk production and cow behaviour, with just milking timing affecting farmer’s sleep. The relationship between milking frequency and timing to milk production, cow and farmer behaviour are multi-directional, therefore there is no one milking frequency or schedule that seems to provide a positive impact on milk production, cow behaviour and farmers sleep at the same time. However, 3-in-2 from mid lactation onwards seems to provide the biggest opportunity to positively impact all three areas. The choice of milking frequency and milking interval chosen on farm will be dependent on the goals that the individual farmer is trying to achieve. This thesis has provided new information for farmers to be able to make that choice with more confidence in the likely outcome
Informal and non-market operations in activity systems
No full textMeasuring informal and non-market activities: a representative survey of Kanak households in the indigenous villages of New Caledonia. In 2011, a survey was conducted to examine the role of agricultural activities (agriculture, breeding, fishing and hunting) in the economies of Kanak households living in such villages in New Caledonia. In total, 1429 domestic groups have been interviewed. The survey focused on the activities performed during 2010 and was representative of the indigenous population at national level as well as in 10 areas within the 3 provinces of New Caledonia. In order to allow people to use them for further analysis, this paper describes the conceptual framework, the nature and the quality of the data. A copy of the data collected is available via the following link: https://dataverse.cirad.fr (doi:10.18167/DVN1/VWWVXU). In order to allow people to use them for further analysis, this paper describes the conceptual framework, the nature and the quality of the data
Coloniality and racialization of informality
No full textThis article is inspired by Finn's work which historizes the structure of formal–informal dialectic in Africa, arguing that the origin dates to the colonial era. I extend Finn's argument through the prism of formal–informal as a racialized binary embedded in the coloniality of Africa's socio-spatial policies. Drawing insights from African cities generally and Lagos in particular, I argue that the formal–informal binary has always been a tool of colonial domination, which (re)produces and maintains racial hierarchies and racialized displacement in contemporary times. This provides a useful frame to understand and challenge the hierarchical positioning of informality relative to formality
Mapping groundcover of clover species in hill pastures in Wairarapa
No full textTokaroa Farm (608 ha) with sheep and beef in the Wairarapa has predominantly sunny, north-facing slopes. Average annual rainfall is 810 mm with three months summer-dry. High quality pasture is needed in late winter/early spring for lactating stock and in spring to finish stock early. The survey mapped the distribution of resident subterranean (sub) and white clovers across four land classes based on slope and aspect. ArcGIS identified 60 GPS points that were visually assessed in December 2019 and November 2021. At the majority of points in both years, both white and sub clover were present. In 2019, white clover groundcover was 18.1% and higher (P<0.05) than sub clover at 12.6%. Management class had no effect. In 2021 there was no species effect (both ~11%) but there was a trend (P=0.062) for less white clover groundcover in the ‘shady’ class (6.7%) than the ‘flat’ class at 17.5%. Pasture management was focused on promoting early season sub clover, but the unexpectedly high groundcover of white clover provided feed during wetter than average summers. Understanding the continuum from summer-dry annual sub clover areas to summer-wet perennial white clover dominance across New Zealand pastures provides tools for the selection and management of appropriate legumes
Saltwater intrusion from an estuarine river: A field investigation
No full textEstuarine rivers provide critical pathways for seawater to travel upstream of the coast and salinize adjacent aquifers. However, this salinization mechanism (forthwith termed riparian saltwater intrusion) has received relatively little attention compared to saltwater intrusion (SI) at the coast. Time series measurements of river and groundwater freshwater head and specific conductance (SC), as well as horizontal river-aquifer hydraulic gradient were collected at transects of piezometers perpendicular to an estuarine river in Ōtautahi Christchurch, Aotearoa New Zealand. The uncertainties of freshwater head and hydraulic gradient were estimated using error propagation methods. Discrete Fourier Transforms were applied to river and groundwater freshwater head and SC time series data, which confirmed the tidal influence in both systems. Cross–correlation analyses of river and groundwater freshwater heads showed very strong relationships with varying time lags. Hydraulic gradients and river SC fluctuated with tides, resulting in the alternation of SI (increase in groundwater SC) and saltwater retreat (decrease in groundwater SC) with various time delays that may be driven by cyclic flow processes. While riparian SI occurred in most piezometers, the hydraulic gradient on the outside of the river meander was steeper than on the inside of the river meander resulting in less SI. Although positive hydraulic gradient (aquifer to river flow direction) occurred most of the time at all sites, land subsidence and climate change conditions of sea–level rise, increased drought, and decreased river flows could increase the occurrence of negative hydraulic gradient, which may result in increased groundwater salinization
Geeky geckos: Using photography and a software package to identify individuals of Woodworthia brunnea
No full textUnderstanding basic life-history parameters of a population and obtaining accurate estimates of population size are essential to making evidenced-based decisions regarding conservation strategies. Estimating population size and characterizing life-history parameters can be effected using mark-recapture studies, which necessitate the ability to recognize individuals. To date, no methodology has been developed for using photography to identify individuals of Woodworthia brunnea. The aim of this project was (1) to develop an effective photographic method for identifying individuals of W. brunnea, and (2) to apply our new methodology to the second year of an ongoing lizard monitoring project on Banks Peninsula. Using Orana Wildlife Park’s captive population of Woodworthia geckos, we developed our photography techniques and tested the effectiveness of the computer programme I3S Pattern in identifying individual geckos. We then conducted three rounds of lizard monitoring at 17 sites across Banks Peninsula from December 2022 – May 2023, photographing each gecko found in our lizard lodges and identifying recaptured individuals in our second and third rounds of monitoring. We found that iris photographs provided more accurate individual identifications than did dorsal photographs using I3S Pattern, but that the accuracy of identifications varies with photograph quality. We also found that dorsal photographs are effective within a field season at confirming identifications made by I3S Pattern. We do not recommend using dorsal photographs alone between field seasons because data from Orana Wildlife Park’s geckos demonstrated that dorsal patterns can fade significantly over five years. Future work will determine how stable iris patterns are over time
Direct real estate, securitized real estate, and equity market dynamic connectedness
No full textThe paper’s objective is to scrutinize the dynamics of connectedness across returns of three markets, including direct real estate, securitized real estate, and stock markets. Through the connectedness index approach, the results indicate a significant degree of connectedness, which increases sharply during the recent global financial crisis. The net directional connectedness is volatile and time-dependent, yet the dominant shock transmitting role of the securitized real estate is pronounced during the GFC. While the direct real estate market plays as a dominant shock information receiver from the markets of securitized real estate and stocks in Australia, Canada, France, and the UK, it appears to shape other markets in the context of the US. Given the fact that the securitized real state is considered as the hybrid of the conventional real estate market and the stock market, we further note that the securitized real estate is more linked with its underlying market. Several implications for investors and policymakers are discussed
Global drivers of herbicide-resistant weed richness in major cereal crops worldwide
Get PDFBACKGROUND: The number of herbicide-resistant weeds differs across the globe but the reasons for this variation are poorly understood. Taking a macroecological approach, the role of six drivers of herbicide resistance in a country was examined for barley, maize, rice and wheat crops worldwide. Drivers captured agronomic measures (crop harvested area, herbicide and fertilizer input) as well as sources of sampling bias that result in under-reporting of herbicide resistance (human population density, research intensity and time since the first record of resistance).
RESULTS: Depending on the crop, best subset regression models explained between 60% and 80% of the variation in herbicide-resistant weeds recorded in countries worldwide. Global prevalence of herbicide-resistant weeds is likely underestimated, especially in countries with limited capability in herbicide research. Numbers of resistant weeds worldwide will continue to increase. Agricultural intensification, captured by fertilizer and herbicide input, as well as further expansion of crop harvested area are primary drivers of future herbicide-resistant weeds.
CONCLUSION: Because the evolution of herbicide resistance lags behind the selection pressures imposed by fertilizer and herbicide inputs, several countries (e.g. Brazil, South Africa, Uruguay) appear to exhibit a ‘herbicide resistance debt’ in which current agronomic conditions have set the scene for higher numbers of herbicide-resistant weeds than currently observed. Future agricultural expansion will lead to more herbicide-resistant weeds, especially in developing countries as their economies grow and where herbicide resistance is currently under-reported. A global strategy for increasing national capability in herbicide resistance research is needed.Open access publishing facilitated by Lincoln University, as part of the Wiley - Lincoln University agreement via the Council of Australian University Librarians
Antibiotic resistance and phylogenetic profiling of Escherichia coli from dairy farm soils; organic versus conventional systems
Get PDFThe prevalence and spread of antimicrobial resistance (AMR) as a result of the persistent use and/or abuse of antimicrobials is a key health problem for health authorities and governments worldwide. A study of contrasting farming systems such as organic versus conventional dairy farming may help to authenticate some factors that may contribute to the prevalence and spread of AMR in their soils. A case study was conducted in organic and conventional dairy farms in the South Canterbury region of New Zealand. A total of 814 dairy farm soil E. coli (DfSEC) isolates recovered over two years were studied. Isolates were recovered from each of two farms practicing organic, and another two practicing conventional husbandries. The E. coli isolates were examined for their antimicrobial resistance (AMR) against cefoxitin, cefpodoxime, chloramphenicol, ciprofloxacin, gentamicin, meropenem, nalidixic acid, and tetracycline. Phylogenetic relationships were assessed using an established multiplex PCR method. The AMR results indicated 3.7% of the DfSEC isolates were resistant to at least one of the eight selected antimicrobials. Of the resistant isolates, DfSEC from the organic dairy farms showed a lower prevalence of resistance to the antimicrobials tested, compared to their counterparts from the conventional farms. Phylogenetic analysis placed the majority (73.7%) of isolates recovered in group B1, itself dominated by isolates of bovine origin. The tendency for higher rates of resistance among strains from conventional farming may be important for future decision-making around farming practices Current husbandry practices may contribute to the prevalence and spread of AMR in the industry
Body odours as lures for stoats Mustela erminea: Captive and field trials
Get PDFEradication and control methods to limit damage caused to native biota in New Zealand by the stoat (Mustela erminea) rely on effective lures for trapping and detection devices, such as cameras. Long-life semiochemical lures have the potential for targeting stoats in situations where food-based lures are of limited success. The attractiveness of body odours of captive stoats was tested in a series of captive animal and extensive field trials to investigate their potential as trapping and monitoring lures. Stoats approached and spent significantly more time sniffing stoat urine and scats and bedding from oestrous female stoats than a non-treatment control. The bedding odours were attractive in both the breeding and the non-breeding season. Stoats also spent significantly more time sniffing oestrous stoat bedding than female ferret bedding, but the ferret odour also produced a significant response by stoats. In the field trials, there were no significant differences between the number of stoats caught with food lures (long-life rabbit or hen eggs) compared with oestrous female or male stoat bedding lures. These results indicate the potential of both stoat bedding odour and the scent of another mustelid species as stoat trapping lures that likely act as a general odour attractant rather than a specific chemical signal of oestrus