Plant pigments     

Stafford HA 《Science (New York, N.Y.)》1976,191(4232):1167

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Mapping Infestations of Potato Cyst Nematodes and the Potential for Spatially Varying Application of Nematicides     

Evans  K.  Webster  R.  Barker  A.  Halford  P.  Russell  M.  Stafford  J.  Griffin  S. 《Precision Agriculture》2003,4(2):149-162

The most important constraint to potato production in the UK is the damage caused by the potato cyst nematodes (PCN) Globodera pallida and Globodera rostochiensis. These are serious pests, capable of causing substantial yield loss. Modern management systems depend heavily on nematicides which, at c. £360 ha^–1 for granular and c. £550 ha^–1 for fumigant nematicides, are costly to use. Mapping field infestations of PCN gives growers the option of applying nematicide variably across their fields. We intensively sampled a field, infested with G. pallida, before and after potatoes were grown and used the results to consider decisions the grower might have taken and to examine the consequences of various actions. Sampling intensity is important in generating accurate maps. In our results, spatial independence in PCN counts occurred at about 60 m, although there was also evidence of spatial independence at a range of 10–20 m in intensively sampled areas of the field. A strategic requirement to keep PCN population densities small, rather than the more tactical objective of avoiding yield loss, would mean blanket treatment of infested fields with granular nematicide. Maps could then be used to target hot spots of PCN infestation for additional treatment with fumigant. This procedure would avoid blanket treatment with both types of nematicide, thereby diminishing the cost of chemicals applied and reducing possible environmental damage. However, the inverse relationship between pre-planting population density and multiplication rate of PCN makes it difficult to devise safe spatial application procedures, especially when the pre-planting population density is just less than the detection threshold.  相似文献   

The effect of different combinations of lignocaine,ketoprofen, xylazine and tolazoline on the acute cortisol response to dehorning in calves     

KJ Stafford  DJ Mellor  SE Todd  RN Ward  CM McMeekan 《New Zealand veterinary journal》2013,61(5):219-226

AIMS: The aims of this study were (a) to evaluate the effect of xylazine and tolazoline, with and without lignocaine, on the cortisol response of calves following amputation dehorning and (b) to assess the effect of a non-steroidal anti-inflammatory drug (ketoprofen) and local anaesthesia on the cortisol response of calves to amputation dehorning.

METHODS: Plasma cortisol concentrations were measured in 100 dehorned or non-dehorned 3-month-old calves over an 8-h period following five different sedative/analgesic or control treatments. Sedative/analgesic treatments were: control (no anaesthesia); local anaesthesia and ketoprofen; local anaesthesia and xylazine; local anaesthesia, xylazine and tolazoline; and xylazine only. Within each sedative/analgesic treatment group, half the calves (n=10 per group) were amputation dehorned and half were not dehorned.

RESULTS: The change in plasma cortisol concentrations in calves dehorned after being given ketoprofen and local anaesthesia did not differ significantly from that of non-dehorned control calves for at least 8 h. In contrast, the cortisol response of dehorned calves not given analgesic drugs peaked 30 min after dehorning and lasted >4 h. Xylazine injected before dehorning significantly reduced but did not eliminate the peak of the cortisol response. When both xylazine and local anaesthesia were administered before dehorning the peak in the cortisol response was virtually eliminated. In the dehorned calves that received xylazine with or without local anaesthesia, cortisol concentration increased significantly 3 h after dehorning and did not return to baseline until at least 5 h later. When tolazoline was administered shortly after xylazine, it caused a marked cortisol response, higher than the response to any other treatment.

CONCLUSIONS: Combining ketoprofen and local anaesthesia minimised the cortisol response, and by inference the pain- induced distress, following amputation dehorning in calves. Xylazine reduced the initial cortisol response to dehorning but not as much as when local anaesthesia was also given. The increase in cortisol concentration from 3–8 h after dehorning in calves given xylazine alone or in combination with local anaesthesia suggests that calves experienced pain-induced distress during this time and that xylazine had no long-term analgesic effect. Tolazoline, used to reverse the sedative effects of xylazine, caused a marked cortisol response in calves via a mechanism which remains unclear.  相似文献   

The physiological and physical status of single calves at birth in a dairy herd in New Zealand     

TJ Diesch  KJ Stafford  RN Ward 《New Zealand veterinary journal》2013,61(5):250-255

AIM: To determine the physiological status of calves at birth and the perinatal factors that might predispose newborn calves to debility and death, using criteria previously established for newborn lambs.

METHODS: Friesian mixed-aged cows and heifers on a dairy farm in New Zealand that were close to calving were separated from the main herd and observed 24 h a day until they calved. Cows in which labour did not progress for over 1 h or which were in distress were assisted. About 12–13 min after birth, rectal temperature was measured and a blood sample was taken from each calf. The packed cell volume (PCV) and plasma lactate, glucose and fructose concentrations were determined. The time to stand for each calf and the air temperature and weather conditions at birth were recorded.

RESULTS: The parameters measured were within normal ranges for newborns for the majority of calves. Calves sired by an Angus bull and born to heifers (AngusX) had significantly higher plasma lactate and fructose concentrations than Friesian calves born to cows, but there were no significant differences between the two breeds in any of the other parameters measured. Calves of both breeds born with assistance had significantly higher plasma lactate concentrations than those born without. Friesian calves that were assisted at birth had significantly lower PCvs and took significantly longer to stand than calves born without assistance. Assisted AngusX calves were significantly heavier than their unassisted counterparts. Calves born during windy and wet weather and when air temperatures were below 10°C had lower rectal temperatures, took longer to stand and had higher plasma glucose concentrations than those born in dry weather and when air temperatures were above 10°C.

CONCLUSIONS: Calves with physiological parameters outside the normal range had experienced difficult labour and/or intrapartum hypoxaemia. Placental insufficiency and maternal undernutrition during late pregnancy did not apparently contribute to neonatal problems in the present study.  相似文献   

Sucking behaviour of hand-reared newborn dairy calves     

KJ Stafford  DJ Mellor  R Corner 《New Zealand veterinary journal》2013,61(4):246-248

AIM: To determine the feeding ability of calves during the first 4 days after birth.

METHODS: The sucking behaviour of 171 dairy calves, fed from individual bottles during the first 4 days after birth, was evaluated by quantifying the volume of colostrum consumed, the duration of feeding, and speed of drinking. Calves had been separated from their mothers and brought into a rearing shed in the morning, when <24 h of age, and were offered 2 L colostrum from a bottle in the afternoon of the same day, and twice daily thereafter.

RESULTS: Newborn calves became efficient suckers from bottles within 24 h of removal from their dams (collection). On the day after birth, 95% of calves drank the 2 L of colostrum offered during the afternoon feed, and by Day 4 virtually all calves (99%) drank this amount. Calves that had inadequate colostrum from their dam were more likely to drink all 2 L offered after collection, but a small number of calves that had not had colostrum from their dams and drank <500 ml at the afternoon feed following collection were likely not to drink 2 L on the following days. However, calves that did not drink all 2 L on Day 1 were not disadvantaged in comparison to those that did, in that they were equally likely to drink 2 L on Day 4.

CONCLUSIONS: The majority of calves became efficient drinkers within 48 hours of birth, but a small number of slow feeders may need individual feeding at least up to 4 days after birth.  相似文献   

The experience of dog bites: A survey of veterinary science and veterinary nursing students     

AAF Wake  KJ Stafford  EO Minot 《New Zealand veterinary journal》2013,61(3):141-146

AIM: To investigate the circumstances of dogs biting people in New Zealand.

METHODS: Veterinary science and veterinary nursing students enrolled at Massey University in 2003 completed a questionnaire detailing their lifetime experience of dog bites and their opinions of dog control legislation.

RESULTS: The response rate was 100%. There were 228 completed responses to the survey, and 87 (38%) respondents had been bitten by a dog. Most bites caused minor injury, but 17 (20%) required medical attention. Male respondents were more likely to have been bitten. The highest proportion of respondents (27; 31%) had been bitten while between 6 and 10 years of age, and the hand was the part of the body most often injured. Eighteen (21%) bites involved a stranger's dog, but most bites were by a dog known to the victim. Respondents from rural areas were three times more likely to have been bitten than city dwellers. The victim's home was the place where most (31; 36%) bites occurred. Male dogs were responsible for a larger proportion of bites (38; 44%) than females (24; 28%); respondents were unsure about the sex of the remainder of the dogs (25; 29%) that bit them. Protecting the home, play, accidents, rough handling and pain were identified as the common reasons for dogs to bite. Most (46; 52%) respondents did not believe legislation could have prevented their bite. Only four (5%) bites were reported to authorities.

CONCLUSION: Rural dwellers, people with more experience of dogs, children <11 years of age, and male respondents were bitten by dogs most often. Only legislation relating to the fencing of dog owners′ properties may have prevented a reasonable proportion (25; 29%) of the bites reported here.  相似文献   

Prevalence of nematode infection and faecal egg counts in free-range laying hens: relations to housing and husbandry     

C.M. Sherwin  M.A.F. Nasr  E. Gale  M. Petek  K. Stafford  M. Turp 《British poultry science》2013,54(1):12-23

1. Faecal samples from 19 commercial, 65 week old free-range egg laying flocks were examined to assess the prevalence and number of parasitic nematode eggs. Data were collected to characterise the housing, husbandry, behaviour and welfare of the flocks to examine possible relationships with the egg counts.

2. Eggs of at least one genus of nematode were present in the faeces of all 19 flocks. Heterakis eggs were detected in 17 (89%) flocks, Ascaridia in 16 (84%), Trichostrongylus in 9 (47%), and Syngamus in 6 (32%). Faecal egg counts (FEC) were greatest for Ascaridia and Heterakis.

3. For each nematode genus, there was no significant difference in FEC between organic (N?=?9) and non-organic (N?=?10) flocks, or between static (N?=?8) and mobile (N?=?11) flocks.

4. FEC were correlated with a range of housing, husbandry and management practices which varied between the nematode genus and included depth of the litter, percentage of hens using the range, and number of dead hens. Statistical analysis indicated relationships with FEC that included light intensity above the feeder, indoor and outdoor stocking density, fearfulness in the shed and on the range, distance to the nearest shelter, and swollen toes.

5. None of the FEC for any of the genera was correlated with weekly egg production or cumulative mortality.

6. Although nematode FEC were highly prevalent among the flocks, the overall lack of relation to other welfare and production measures suggests that these infections were not severe.  相似文献   

Management and Welfare of Farm Animals. The UFAW Farm Handbook (5th Edtn)     

Professor Reviewed by Kevin Stafford 《New Zealand veterinary journal》2013,61(6)

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Special issue on 6th European Conference on Precision Agriculture and 2nd Precision Crop Protection Conference     

John V. Stafford 《Precision Agriculture》2009,10(5):371-371

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Demographics,farm and reproductive management strategies used in Australian automatic milking systems compared with regionally proximal conventional milking systems          下载免费PDF全文

DM Keeper  KL Kerrisk  JK House  SC Garcia  P Thomson 《Australian veterinary journal》2017,95(9):325-332

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