Heifer replacements

AFBI – CAFRE heifer rearing survey

The aim of the survey was to assess heifer rearing management practices and to establish priorities for technology transfer. The survey was jointly conducted with AFBI, Hillsborough designing the survey questionnaire and the farmer interviews conducted by CAFRE Dairying Development Advisers. Areas of management being assessed included: calf rearing, breeding management, health and welfare and attitudes to research and technology transfer. A summary of the results is available through the link below.

• Heifer survey results

Attitudes to technology transfer on Northern Ireland dairy farms

The transfer of technology from research to farm practice is critical for progress within the agriculture industry. Without an understanding of how information is obtained and the processes involved when adopting new technology, efficient technology transfer is difficult. Therefore, the objective of this study was to examine the current attitudes to technology transfer amongst Northern Ireland dairy farmers and ascertain what factors influence these attitudes.

Materials and methods

A stratified random sample of 300 dairy farms was selected from the Northern Ireland population of 3252 farms having 30 or more dairy cows in June 2005, (Northern Ireland Agricultural Census). The sample was stratified by county and dairy herdsize (30-50, 51-80 and 80 plus dairy cows) andselected to ensure equal representation within each group. Only farms with dairy heifer rearing enterprises were included in the study. In total 247 farmers participated in an interview-based questionnaire. SPSS software was used for statistical analysis of data. Statistical associationtests were performed, including non-parametric statistical tests andcontingency table tests using Chi Square tests. The questionnaire consisted of six sections divided into 107 main questions. Within the section aimed to gather background information of farms, respondents were asked to indicate the level of education/training they received from a pre-set list, which included vocational and non vocational training programmes.

Results and discussion

Data demonstrated that evening meetings were the more commonly attended technology transfer event (Table 1). Despite their popularity, evening meetings only ranked sixth regarding their effectiveness as a method of technology transfer, with popular press articles being the most highly rated (Table 1). Although time was a major constraint, farmers were keen to learn (58%) with <3% not interested in learning new practices. For every 1 unit increase in the size of milking herd, the odds of the farmers attitude to learning being ‘examine if have to’ decreased by a factor of 0.008 (95% CI= 0.985-0.999; P<0.05). Farmer age was significantly associated with style of learning demonstrated with farmers older than 40 being twice as likely (95% CI= 1.05-3.55) to be non-specific in their learning technique. Increasing herd size was associated with differing priority given to areas for future research and differing importance towards considerations when adopting new technology. For example, as herd size increased, non-financial rewards (r=0.09; P<0.10) and who/where research was performed (r=0.11; P<0.05) became more important considerations when adopting new technology.

More than 50% of farmers had no formal training. Interestingly, training had a significant impact on the attitude of farmers to learning and the questions asked when adopting new research findings. For example, farmers who had completed a National Diploma or Certificate in Agriculture were 2.9 (95% CI 1.6-5.4; P<0.001) times more likely to rate themselves as keen to learn compared to farmers who had received no formal training. Non specific learning techniques were more likely to be employed as formal education level increased (P=0.06). For example farmers who completed a National Diploma or Certificate in Agriculture were 51% (95% CI 27-96; P<0.05) more likely to be non-specific rather than specific in their attitude to learning compared to farmers with no formal training. A number of considerations when adopting research findings (Table 2) were associated with level of formal training. For example, farmers who indicated some degree of formal education were twice as likely to place importance on being innovative (95% CI= 1.2-3.7; P<0.01) compared with farmers who received no formal education.

NA – not asked during survey

Conclusions

Results demonstrate how producers currently learn of new research findings and the variation with regard to the importance farmers place on factors when considering the adoption of new research ideas. This information will enable more targeted technology transfer in the future.

Acknowledgements

• AgriSearch and DARDNI funding gratefully acknowledged.
• S.J. Morrison, A.F. Carson and D. Matthews (AFBI), M. Mulholland (CAFRE).

An investigation of calf rearing practices on dairy farms in Northern Ireland

Without a detailed understanding of how calf rearing is performed in practice, it is difficult to establish 1) the effectiveness of technology transfer initiatives and 2) how best to focus future research efforts. In view of this, the objective of the current study was to investigate calf rearing practices on Northern Ireland dairy farms.

Materials and methods

A stratified random sample of 300 dairy farms was selected from the Northern Ireland population of 3252 farms with 30 or more dairy cows in June 2005, (Northern Ireland Agricultural Census). The sample was stratified by county and dairy herdsize (30-50, 51-80 and 80 plus dairy cows) andselected with equal proportion of farms from each group, to ensure good representation within the sample. Only farms with dairy heifer rearing enterprises were included in the study. In total 247 farmers participated in an interview-based questionnaire. SPSS software was used to carry outstatistical analysis. Statistical associationtests were carried out which includednon-parametric statistical tests andcontingency table tests using Chi Square tests.

Results

Calves were reared by the farm owner on 62% of farms, with a family member having primary responsibility on 36% of farms. Bull calves were reared for beef enterprises on 35% of farms, whilst 58% of farms sold bull calves at one to two weeks of age, with 4% of farms selling bulls at weaning. On most farms (73%) colostrum was mainly supplied by suckling from the dam. As herd size increased, the calf was more likely to remain with the dam for a shorter period of time (P<0.01). Indeed, for every unit increase in herd size, the likelihood of the calf remaining with mother for >24 hours reduced by a factor of 0.011 (OR= 0.989; CI= 0.989-0.997; P<0.01). Colostrum was administered to every calf via oesophageal feeder on 24% of farms and this practice was more likely to occur as farm size increased (OR= 1.013; 95% CI= 1.007-1.019; P<0.001). During the pre-weaning phase, calves were most commonly housed in individual pens (48%) with larger farms more likely to use group pens (P<0.05) and group feeding systems (P<0.001). However, twice daily bucket feeding was the dominant technique (79% of farms). Within calf accommodation, ventilation was based on natural airflow on 93% of farms.

However, there was a significant herd size effect, with smaller farms less likely to use forced ventilation (OR= 0.992; 95% CI= 0.984-0.999; P<0.05). Milk replacer was used predominantly on 23% of farms, with 77% of producers offering whole milk, of which 58% of producers used milk destined for the bulk milk tank. Calf starter concentrate was made available to calves pre-weaning on 98% of farms, with 88% offering greater than 1kg/day during the week immediately prior to weaning. The delayed introduction of calf starter post-birth was associated with an increased age at first calving (P<0.001). Straw and hay were the most popular forages offered at birth (60 and 30% of farms respectively), during the milk feeding stage (59 and 33% of farms respectively) and at weaning (46 and 28% of farms respectively), with grass silage gaining popularity only at weaning (25% of farms). Although the mean weaning age was eight weeks, 28% of producers weaned at greater than eight weeks. The findings from this study suggest that calf size was the primary criterion used to determine when to wean dairy calves (Table 1).

Conclusion

These results demonstrate that a wide range of practices have been adopted for rearing dairy calves in Northern Ireland. This information will enable focused research to address potential inefficiencies and enable more targeted technology transfer.

Acknowledgements

AgriSearch and DARDNI funding gratefully acknowledged. Appreciation is extended to CAFRE Dairy Development Advisers who collected the information and to participating dairy farmers for their time.

Heifer Liveweight Measuring Tape

The feeding and management of Holstein-Friesian heifers should be geared around achieving a live weight at first calving of 540-580 kg at 23-25 months of age. Monitoring heifer growth by measuring heifers is key to making informed management decisions. AFBI, Hillsborough over the last 10 years have collected a comprehensive dataset on body size measurements during each stage of the rearing period. This has enabled the development of simple and easy assessment of live weight through measurement of heart girth diameter. Measuring tapes scaled with the live weight of Holstein Friesian heifers have been produced for farmers to monitor heifer growth against targets at key management periods, facilitating a cost effective rearing regime. The optimum body size targets developed from the Hillsborough research programme are presented in Table 6.

In terms of deciding when to commence breeding, body size and live weight as well as age are considered important or very important criteria by the majority of producers (90%+). On many dairy farms, visual assessments only made of heifer growth with little weighing or measuring being undertaken (less than 5% of producers according the the AFBI-CAFRE survey). Whilst producers are confident of their ability to identify the optimum size for breeding, the research shows (1) their can be a large difference between actual live weight and that predicted by producers using visual assessment (2) body sizes targeted by producers to commence breeding tend to be larger than optimum.

To use the weighband:

1. restrain the heifer securely in a cattle crush with a locking head-yoke
2. place the weighband over the heifers back just behind the front legs
3. pull the weighband under the heifers belly using a reaching hook
4. read off the heifer weight by lining up the reading line with the weight band scale
5. do not overtighten the weighband - just flatten the hair

More useful links

• Rearing your 2010 herd