The aim of the present study was to identify specific behavioral patterns that contribute to diminished estrus expression in lame cows. Behavioral scan and focal sampling were used to examine the effect of lameness on daily activity budgets, sexual behavior, feeding activities, and body condition score. A total of 59 milking cows (51.8 +/- 1.4 d postpartum) were monitored on a commercial dairy farm for 5 d following estrus synchronization. Overall, lame cows (n = 39) spent proportionately less time elevated on their feet and more time lying down compared with nonlame cows (n = 20). This included lame cows spending less time walking or standing. Overall, the total proportion of scans in which an estrous behavior was observed was very small but tended to be smaller for lame compared with nonlame cows. Throughout a day, lame cows displayed a lower proportion of estrous behaviors in the early morning. Lameness did not affect durations of drinking, grazing, or ruminating, or how these behavioral states fluctuated throughout the day. Similarly, rumination chewing rates were the same for lame and nonlame cows, and there was no association between lameness and dominance/displacement while feeding at a feed-fence. Lame cows did, however, have a slower bite rate at pasture and had a lower body condition score. Lame cows were also nearer the rear of the herd, both as they left the field and when entering the milking parlor. In conclusion, lame cows have longer lying times and spend less time standing, walking, and expressing an estrous behavior. Lame cows also have a lower bite rate at pasture and are more likely to be of lower body condition score.
Successfully using artificial insemination (AI) is defined as getting cows pregnant when the farmer wants them in-calf and making the best use of appropriate genetic potential. Over the past 30 to 50 years, the percentage of animals in oestrus that stand-to-be-mounted (STBM) has declined from 80% to 50%, and the duration of STBM from 15 h to 5 h; both in parallel with a reduction in first-service-pregnancy-rate from 70% to 40%. Meanwhile, the incidence of lameness and mastitis has not decreased; and it takes more than an extra 40 and 18 days, respectively, to get a lame or mastitic cow in-calf compared to healthy herd-mates. The intensity of oestrus is 50% lower in severely lame cows, and fewer lame cows ovulate. Luteal phase milk progesterone concentrations are also 50% lower in lame cows, and follicular phase oestradiol is also lower in non-ovulating lame cows compared to ovulating animals. Furthermore, lame cows that do not ovulate do not have an LH surge, and the LH pulse frequency in their late follicular phase is lower (0.53 v. 0.76 pulses/h). Thus, we suggest that the stress of lameness reduces LH pulsatility required to drive oestradiol production by the dominant follicle. The consequent low oestradiol results in less-intense oestrus behaviour and failure to initiate an LH surge; hence there is no ovulation. A series of experimental studies substantiate our hypothesis that events activating the hypothalamus-pituitary-adrenal axis interfere at both the hypothalamus and the pituitary level to disrupt LH and oestradiol secretion, and thus the expression of oestrus behaviour. Our inability to keep stress at a minimum by appropriately feeding and housing high-production cows is leading to a failure to meet genetic potential for yield and fertility. We must provide realistic solutions soon, if we want to successfully use AI to maintain a sustainable dairy industry for the future.
Sixty-seven Holstein-Friesian cows, from 20 days postpartum, were recruited into the study and fitted with both a pedometer (SAE Afikim) and a Heatime neck collar (SCR Engineers) and allocated a heat mount detector (either scratchcard [Dairymac] or KaMaR [KaMaR]) or left with none, relying only on farm staff observation. Common production stressors and other factors were assessed to determine their impact on the ability of each method to accurately detect oestrus and to investigate effects on the frequency of false-positive detections. Only 74 per cent of all potential oestrus periods (episodes of low progesterone) were identified by combining information from all methods. There was no difference between the methods in terms of sensitivity for detecting 'true oestrus events' (approximately 60 per cent), with the exception of scratchcards, which were less efficient (36 per cent). Pedometers and KaMaRs had higher numbers of false-positive identifications. No production stressors had any consequence on false-positives. The positive predictive values for neck collars or observation by farm staff were higher than those of other methods, and combining these two methods yielded the best results. Neck collars did not detect any of the nine oestrus events occurring in three cows with a body condition score (BCS) of less than 2, and the efficiency of correctly identifying oestrus was also reduced by high milk yield (odds ratio [OR]=0.34). Pedometer efficiency was reduced by lameness, low BCS or high milk yield (OR=0.42, 0.15 or 0.30, respectively).
Postal surveys or personal interviews of 76 recent veterinary graduates and their 49 employers were undertaken to establish their perceptions of good practice when integrating a new graduate into a business and their preferred methods of assessment and development. Practice type and location were the main influences on graduates looking for their first job. Interviews were mostly informal. Employers expected basic veterinary competence and candidates expected good quality support. Most graduates (93 per cent) had their own consultations on the first day. During early consultations 2 per cent of senior vets accompanied the new graduate, 95 per cent of practices provided senior back-up either in person or by telephone but in 3 per cent no back-up was available. Most new graduates (90 per cent) were satisfied with their workload. Three-fifths were on-call within the first week, and 95 per cent within a month. Graduates received calls directly in 45 per cent of practices, in 9 per cent seniors screened the calls, and the remainder used a third party. Assistance from experienced lay staff varied greatly. Discussion of problems was mainly informal. There was little spontaneous feedback and problems resulted from inadequate communication. One in three new graduates left their first job within two years, and one in six identified lack of support, heavy workload, stress or clashes with staff as a primary reason. This high turnover was a problem for employers. From the new graduates' perspectives, initial problems included: being on call (59 per cent), financial aspects (47 per cent) and surgery (43 per cent). Communicating with clients and learning to prioritise jobs were also difficult. New graduates took longer over procedures (79 per cent of employers commented) and required extra back-up (91 per cent) both of which reduced income (59 per cent). Nearly all the seniors felt that their current new graduates had coped 'quite well', although it was claimed that new graduates lacked the ability to talk to clients at the appropriate level, wanted to bring all their scientific knowledge to bear on every case, and often failed to consider the obvious or to appreciate clients' needs. Only 18 per cent of practices had formal and regular review procedures but all monitored the response of clients and watched the new graduate perform. Feedback to their new colleague was considered 'adequate' by 85 per cent of seniors, although 45 per cent of graduates felt they had not received enough. Eighty-three per cent of new graduates felt 'moderately prepared' by their undergraduate course, and 76 per cent of senior vets were 'generally satisfied' Both wanted improvements in extramural studies and increased exposure to routine cases. Senior partners sought greater commitment in the undergraduate curriculum to financial/legal issues and communication skills. Over a third of employers (38 per cent) had a 'great influence' on the choice of continuing professional development courses for their recent graduates. New graduates chose courses to de...
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