Possible answers to Graph 1

1. 2017

2. A winter barley crop, as it is less susceptible to leaf spot compared to spring barley.

3. Favourable weather conditions, warm days followed by wet days. Lack of resistant seeds. Lack of crop rotation. Volunteer diseased seeds from last year’s crop by not cleaning combines and balers between fields.

4. Leaf spot is a fungal disease, it can be prevented by crop rotation, high scores of disease resistance on recommended lists, a good fungicide spraying programme, using a mix of three barley varieties in the one field (feed barley only).

Possible answers to Graph 2

1. The independent variables could be time of the year, type of grazing mixture (PRG only) and ( PRG and clover).

The dependent variables could be daily milk yield (kg/cow) and sward white clover content (%).

2. There is a positive correlation for the first 15 weeks of the year and a negative correlation from week 18 to 50.

3. The perennial ryegrass and clover leads to a higher milk yield for the majority of the year compared to perennial ryegrass only, therefore it would be a more sustainable product.

4. It is more environmentally friendly as it fixes nitrogen from the air due to the Rhizobium bacteria in the root nodules. At a 30% inclusion rate in a sward it can fix up to 50kg of nitrogen per hectare per year. It is highly palatable and contains a higher protein content than grass. Higher milk yields and liveweight gains. Less nitrogen fertiliser required on the farm, therefore, less water pollution and fewer carbon miles .

5. Clover requires higher temperatures for growth above 8 -10°C compared to grass. It will reach its peak yield in the sward during late summer/autumn.

Possible answers to Graph 3

1. The calving interval is the period between the birth of a calf and the birth of the next calf, and if this time is extended it may cause a decrease in the amount of milk and number of calves produced from a cow in her lifetime. This period should be less than 365 days.

2. The dependent variable is the calving interval (days) and the independent variable is the period of time (years).

3. The calving interval has decreased from 396 days down to 387days showing an improvement in national herd fertility.

4. The selection of AI bulls and stock bulls with four- to five-star rating for fertility and ease of calving. Good heat detection methods. Selection of high genetic merit replacement heifers. High body condition score. Good herd health. Feeding programme (trace elements for fertility).

5. A decrease in calving interval days could lead to extra calves, extra replacement heifers, extra milk yield and improved farm output.

Possible answers to Table 1

1. Accidents from machinery/vehicles.

2. More use of technology, safety training, the use of certified equipment, good handling facilities, health and safety certification.

3. Hydrogen sulphide (H2S), carbon dioxide (CO2), ammonia (NH3) and methane (CH4).

4. Good handling equipment, help from another person, have a mobile phone in case of any accidents, do not take risks at calving time or when handling bulls.

5. Slurry gas sensors, organisation of collected farm data using mobile phone apps, human and animal positioning sensors, automatic shut-off sensors, the use of hydraulic pumps instead of PTO-driven machinery.