Keelin O’Driscoll

Does access to open water affect the health of Pekin ducks (Anas platyrhynchos)

Access to open water is considered good for the welfare of Pekin ducks. These studies investigated the effect that the type of water resource, provided over either straw bedding or a rubber mesh, had on measures of duck health. Pekin strain ducklings (n = 2,600) were managed in pens of 100 on straw over a solid concrete floor. In study 1, one of two water resources (nipple, n = 5 pens; wide-lip bell drinker, n = 5 pens), was located directly over the straw. In study 2, one of three water resources (narrow-lip bell drinker, n = 6 pens; trough, n = 5 pens; and bath, n = 5 pens) was located over a rubber mesh. On d 16, 24, 29, 35, and 43, (study 1) or d 21, 29, 35, and 43 posthatch (study 2), 10 birds were selected from each pen and weighed, and then feather hygiene, footpad dermatitis, eye health, gait score, and nostril condition scores were taken. Treatment had no effect on BW in either study, but in study 2, ducks in the open water treatments had higher scores (P < 0.001) than those in the narrow-lip bell drinker treatment by d 43. In study 1, treatment had no effect on hygiene scores, but scores increased over time (P < 0.001). In study 2, ducks in the narrow-lip bell drinker treatment were dirtier than those in the bath treatment (P = 0.01), with those in the trough treatment being intermediate. In both studies, ducks with bell drinkers had worse gait scores than those in the other treatments (study 1, P < 0.01; study 2, P < 0.05). Treatment had no effect on eye health scores. However, ducks were less likely to have dirty nostrils when provided with more open water resources in both studies (P < 0.01), or were less likely to have blocked nostrils in the trough and bath treatments than in the narrow-lip bell drinker treatment in study 2 (P = 0.01). Provision of open water, particularly over a properly constructed drainage area, improved some aspects of duck health (improved feather hygiene and BW, and fewer dirty and blocked nostrils). However, further work is needed to investigate these treatments on a commercial scale.

The Effect of Out-Wintering Pad Design on the Synchrony of Dairy Cow Behavior

The study investigated differences in behavior synchrony of dairy cows during the winter confinement period when managed in 1 of 3 out-wintering pad (OWP) systems, or indoors in free-stall housing. There were 2 replicates of each treatment, and observations were carried out on 3 recording occasions in January and February 2006. On each recording occasion, behavior was recorded every 30 min between 0600 and 0130 h the following day (n = 40). The outcomes for measurement were eligible cows lying (ECL), cow comfort index (CCI), and proportion of animals feeding (AF). Autocorrelation as an indicator of synchrony was calculated using the Durban-Watson statistic and compared across treatments. A centered moving average was calculated, used to obtain the residual, and compared between treatments. Low autocorrelations were recorded in free stalls (39.6 +/- 0.1%), indicating lower temporal behavioral synchrony than in the 3 OWP designs. Overall, the greatest proportion of ECL, CCI, and AF occurred in free stalls (60%). However, high proportions (>90%) of ECL were recorded on OWP in the early morning, whereas the range of ECL in free stalls (22 to 87%) was lower. The low overall proportions for ECL (44, 52, and 54%) and CCI (48, 55, and 58%) in the OWP were caused by the cows standing without feeding during daylight hours. Nevertheless, these cows performed more synchronized lying at night, and their behavior was more highly autocorrelated (65.9 +/- 0.1, 73.3 +/- 0.1, and 52.3 +/- 0.1%) than cows in free stalls. Synchrony of behavior is part of the normal behavior repertoire of herd-living animals such as dairy cattle, and OWP may promote a more natural circadian behavior pattern than do free-stall systems. It is important that indices such as CCI and ECL are utilized at appropriate times of the day, when cows are expected to lie; that is, during the evening time. Estimated acceptable levels of these indices may be dependent on the confinement system employed.

A reduction in milking frequency and feed allowance improves dairy cow immune status

Twice-daily milking is the most common milking regimen used globally. A reduction in milking frequency to once daily, combined with a reduced feed allowance (FA), could reduce the physiological stress associated with the transition to peak milk production, and hence improve immune function. This study investigated how milking frequency and FA affect dairy cow immune status. Cows (n = 48) were milked once a day (OAD) or twice a day (TAD) on 1 of 2 FA: high (HFA) or low (LFA), in a 2 × 2 factorial arrangement of treatments. After the mean calving date of March 11, HFA cows were offered ad libitum grass silage and 7 kg of concentrates/cow per day until March 22, then 4 kg of concentrates/cow per day until April 17, and thereafter allocated 31.3 kg of dry matter (DM) grass/cow per day. The LFA cows were offered 4 kg of concentrates/cow per day, 1 kg of concentrates/cow per day, and allocated 19 kg of DM grass/cow per day for the same respective periods. Milk yield was recorded daily and body condition score weekly, and somatic cell count was performed at approximately 2-wk intervals. Blood samples were collected prepartum (d -7 to -1) and at d 1 to 7, d 14 to 21, and d 42 to 49 postpartum. Total and differential leukocyte percentage, IFN-γ production in response to concanavalin A and phytohemagglutinin, and cortisol, haptoglobin (Hp), and serum amyloid A (SAA) concentrations were evaluated. Cows milked OAD had reduced milk yield and body reserve mobilization, but higher somatic cell counts. Milking frequency and diet had no effect on total leukocyte counts. Cows milked OAD had a higher lymphocyte percentage and lower monocyte percentage, and tended to have a lower neutrophil percentage than cows milked TAD. In addition, the LFA cows had a higher eosinophil percentage than cows fed the HFA. Milking frequency and diet had no effect on IFN-γ, Hp, SAA, or cortisol production. Utilization of strategies to reduce milk yield at the beginning of the lactation could not only reduce body reserve mobilization, but also help to maintain a functioning immune system, and thus improve cow welfare.

The effect of out-wintering pad design on dirtiness score, somatic cell score and mastitis incidence in dairy cows.

This study aimed to compare three woodchip out-wintering pad (OWP) designs, and indoor cubicle housing with regard to cow dirtiness scores during the winter housing period, and udder health during both the winter period and the following lactation, for spring-calving dairy cows. The treatments were: an uncovered (UP) and covered (CP) OWP with a concrete feed apron; an uncovered OWP with self-feed silage pit provided directly on the woodchips (SP); and indoor cubicle housing (IC). Data were compared during 2 years: year 1 was a case study while year 2 was an experimental study. In year 1, treatments were UP (space allowance = 12 m2/cow), CP (6 m2/cow) and IC. In year 2, all three OWP designs (12 m2/cow) were compared with IC. Animals were assigned to treatments at the end of lactation in the autumn, and remained there while dry until calving the following spring. Subsequently, all cows were at pasture during lactation. Outcome measures for analysis were cow dirtiness score, somatic cell score (SCS) and incidence of clinical mastitis during the dry period and during lactation. Quarter milk samples were also taken at drying off, calving and 3 weeks post partum both years, and at approximately 113 days in milk in year 2. Samples were analysed for presence of mastitis-causing agents and SCS was determined. Sub-clinical mastitis was diagnosed when cows had an SCS greater than 200 000, or California mastitis test greater than 1 in at least one quarter. In year 1, cows in CP were dirtier than cows in the other two treatments. These animals also had the highest SCS during lactation and tended to have more mastitis-causing agents isolated from quarter milk samples. In year 2, when all cows were stocked at the same density, cows in the sheltered OWP (i.e. CP) had similar dirtiness scores to cows in cubicles and significantly lower dirtiness scores than cows in the unsheltered OWP designs, i.e. UP and SP. However, there were no effects on SCS or quarter sample results. Cleaning of OWPs stocked at 12 m2/cow reduced cow dirtiness scores. However, cleaning of CP in year 1 when cows were stocked at 6 m2/cow had no effect on dirtiness scores. We conclude that dry cows stocked at 12 m2/cow on OWPs are unlikely to have udder health problems in the subsequent lactation. Furthermore, provision of shelter and cleaning of the woodchips are management factors that help to keep cows clean on OWPs.

Differences in leukocyte profile, gene expression, and metabolite status of dairy cows with or without sole ulcers

Sole ulcers are one of the most severe pathologies causing lameness in dairy cows and are associated with abnormal behavior and impaired production performance. However, little is known about how or whether lameness caused by sole ulcers affects the cow systemically. This study compared hematology profile, leukocyte gene expression, and physiological responses [metabolite, cortisol, the endogenous steroid hormone dehydroepiandrosterone (DHEA), and haptoglobin concentrations] of cows with sole ulcers and healthy cows. Twelve clinically lame cows (lame) were identified as having at least one sole ulcer and no other disorder, and matched with a cow that had good locomotion and no disorders (sound), using days in milk, liveweight, body condition score, and diet. Blood samples were taken from all 24 cows within 24h of sole ulcer diagnosis. Leukocyte counts were obtained using an automated cell counter, cortisol and DHEA concentration by ELISA, and plasma haptoglobin, urea, total protein, creatine kinase, and glucose were analyzed on an Olympus analyzer. Expression of 16 genes associated with lameness or stress were estimated using reverse transcription-PCR. Data were analyzed using the MIXED procedure in SAS software (version 9.3; SAS Institute Inc., Cary, NC). Lame cows had a higher neutrophil percentage, a numerically lower lymphocyte percentage, and tended to have a higher neutrophil:lymphocyte ratio than sound cows. Serum cortisol and DHEA concentrations were higher in lame than in sound cows. Lame cows also tended to have higher haptoglobin and glucose levels than sound, as well as higher protein yet lower urea levels. Sound cows tended to have higher relative expression of the gene coding for colony-stimulating factor 2 than lame, but in all other cases where differences were detected in cytokine gene expression (IL-1α, IL-1β, CXCL8, and IL-10), relative gene expression in sound cows tended to be, or was, lower than in lame. Relative expression of MMP-13, GR-α, Fas, haptoglobin, and CD62L were, or tended to be, higher in lame than sound cows. A high neutrophil:lymphocyte ratio in combination with higher cortisol levels in cows with ulcers is indicative of physiological stress. Moreover, increased DHEA and a higher cortisol:DHEA ratio, as well as a tendency for higher haptoglobin levels and increased haptoglobin mRNA expression, are indicative of systemic inflammation. Increased cytokine mRNA expression indicates activation of the immune system compared with healthy cows. Increased expression of MMP-13 mRNA has been found in cows with impaired locomotion and thus could be implicated in development of claw horn disorders.

The effect of dry cow winter management system on feed intake, performance and estimated energy demand.

This research compared three wood-chip out-wintering pad (OWP; an unsheltered OWP; a sheltered OWP (both with a concrete feed apron); and an unsheltered OWP with silage provided directly on top of the wood-chip bedding (self-feed OWP)) designs and cubicle housing with regard to dairy cow performance during the pre-partum period, and for 8 weeks post partum. Data were compared during 2 years. In Year 1, the unsheltered (space allowance = 12 m2 per cow) and sheltered (6 m2 per cow) OWPs were compared with cubicle housing (n = 49 cows per treatment). In Year 2, all three OWP designs (12 m2 per cow) were compared with cubicle housing (n = 24 cows per treatment, split into two replicates). Animals were dried off and assigned to treatment in the autumn, and remained there until calving in spring. Subsequently, they were managed at pasture during lactation. Outcome measures for analysis during the pre-partum period were feed intake, live weight, body condition score (BCS), heat production and heat loss, and post-partum were live weight, BCS, milk yield and milk composition. In Year 1, all cows had a similar live weight, but both pre-partum and at calving cows on the unsheltered OWP had a lower BCS than cows in cubicles (P < 0.05). However, in Year 2, there were no differences in either live weight or BCS. In Year 1, cows in the unsheltered OWP produced less heat than in cubicles (P < 0.05), but in Year 2, there was no treatment effect. In both years, cows in unsheltered OWPs lost more heat than cows in the sheltered OWP (P < 0.001). Treatment had no effect on milk composition either year. However, in Year 2, cows in the self-feed OWP had higher milk yields than the other treatments (P < 0.05). The lower BCS and heat production values in unsheltered treatments during Year 1 were probably because of higher rainfall and wind-speed values of that year. However, in both years, live weight in all treatments increased pre partum, and BCS did not decrease, indicating that unsheltered cows did not need to mobilise body reserves. Thus, OWPs could be a suitable pre-partum alternative to cubicle housing for dry dairy cows with regard to some aspects of dairy cow productive performance. However, further research should be carried out to investigate longer-term effects.

The economic, environmental and welfare implications of alternative systems of accommodating dairy cows during the winter months

Pasture grazed in situ is one of the most competitive and sustainable feeding systems for dairy cows globally because of a low environmental footprint, the potential for excellent animal welfare and the relatively low cost in the production and utilisation of the feed. However, because of seasonal variation in grass production and inclement weather conditions, dairy cattle may have to be accommodated and/or fed off pasture. There are numerous infrastructural options for achieving this and the focus of the present paper was to review the research and discuss the merits of these alternate animal accommodation systems, focussing on the impact that they have on the environment, animal welfare and farm profitability relative to pasture-only systems. Research data showed that dairy cow welfare can be protected in a range of well managed alternative winter accommodation. In a temperate climate, such as that which pertains in Ireland, adequately fed adult cattle will not use extra feed energy to maintain body temperature when accommodated outdoors and exposed to the effects of wind, rain and low temperatures, as the heat produced from the digestion of feed is in excess of the requirement to maintain body temperature. The main welfare challenge of a wintering system in such conditions is to provide suitable lying facilities for cows to express normal lying behaviour and provide adequate feed. The primary economic focus of pasture-based systems should be to maximise the length of the grass-grazing season and, consequently, to minimise the period off paddock. Provided that body condition targets can be met, there will be minimal effect of wintering system on dairy cow productivity and the only economic differences will be in costs. The cost analysis should combine the capital costs of construction financed over its useful life and the annual operating costs, including labour.