No description available.

A RCBD study with 19 first lactation Holsteins was conducted to investigate the effects of replacing 10% of concentrate with alfalfa baleage on lactation performance. Intake of DM was greater (P=0.02) for low forage (21.92 kg/d) than high forage diet (21.18 kg/d). Digestibility of DM was similar (P=0.4) between high (39.65%) and low forage diet (41.64%). Yield of 4% FCM was similar by diet but greater (P=0.01) for less than or equal to 251 d (29.36 kg/d) than greater than 251 d DIM cows (28.47 kg/d). Feed efficiency tended to be greater (1.42 versus 1.35; P=0.056) for high forage diet but was greater (1.44 versus 1.35; P=0.003) for cows less than or equal to 251 d DIM. Fat and lactose contents were similar by diet while protein tended to be greater (P=0.07) for low forage diet and SNF (8.93% versus 9.06%; P=0.04) was greater for low forage diet.

Transition dairy cows are vulnerable to negative consequences of depressed feed intake due to a transient state of negative energy balance that predisposes them to disease after calving. Competition has been identified as one factor that can decrease feeding activity in mid-lactation cows, but the effects of competition on the transition cow are less well understood. The objective of this study was to test the effect of a competition on the behaviour and feed intake of transition cows. Standing behaviour, feeding behaviour and dry matter intake (DMI) was monitored from 1 wk before to 2 wk after calving for 110 Holstein dairy cows. Social behaviour was recorded in the week before calving. Cows were assigned to a competitive (2:1 cows:bin) or non-competitive (1:1 cow:bin) treatment at the start of the study. Treatment groups were balanced for parity and baseline feeding data, resulting in 8 primiparous and 10 multiparous cows per treatment. Competition dramatically increased the number of agonistic behaviours between cows at the feeder. Primiparous cows showed no change in either feeding or standing behaviour when fed in a competitive environment; however, they increased their total meal duration and within-meal intervals in the wk -1 before and wk +1 after calving. In wk -1 before calving, competitively fed multiparous cows increased the frequency of visits to the feeder but consumed less feed at each visit, resulting in decreased daily DMI. Throughout the experiment, multiparous cows fed competitively spent less time eating at each visit and ate at a faster rate, particularly during the 2 wk after calving. Multiparous cows on the competitive treatment also increased the time they spent standing (without eating) compared to cows on the non-competitive treatment. Feeding rate was negatively correlated with social status in multiparous cows. In summary, the results of this study indicate that restricting access to the feeder increases agonistic behaviours regardless of parity, and cows of different parity and social status respond differently in terms of feeding and standing behaviour.

No description available.

Transition dairy cows are vulnerable to negative consequences of depressed feed intake due to a transient state of negative energy balance that predisposes them to disease after calving. Competition has been identified as one factor that can decrease feeding activity in mid-lactation cows, but the effects of competition on the transition cow are less well understood. The objective of this study was to test the effect of a competition on the behaviour and feed intake of transition cows. Standing behaviour, feeding behaviour and dry matter intake (DMI) was monitored from 1 wk before to 2 wk after calving for 110 Holstein dairy cows. Social behaviour was recorded in the week before calving. Cows were assigned to a competitive (2:1 cows:bin) or non-competitive (1:1 cow:bin) treatment at the start of the study. Treatment groups were balanced for parity and baseline feeding data, resulting in 8 primiparous and 10 multiparous cows per treatment. Competition dramatically increased the number of agonistic behaviours between cows at the feeder. Primiparous cows showed no change in either feeding or standing behaviour when fed in a competitive environment; however, they increased their total meal duration and within-meal intervals in the wk -1 before and wk +1 after calving. In wk -1 before calving, competitively fed multiparous cows increased the frequency of visits to the feeder but consumed less feed at each visit, resulting in decreased daily DMI. Throughout the experiment, multiparous cows fed competitively spent less time eating at each visit and ate at a faster rate, particularly during the 2 wk after calving. Multiparous cows on the competitive treatment also increased the time they spent standing (without eating) compared to cows on the non-competitive treatment. Feeding rate was negatively correlated with social status in multiparous cows. In summary, the results of this study indicate that restricting access to the feeder increases agonistic behaviours regardless of parity, and cows of different parity and social status respond differently in terms of feeding and standing behaviour.

No description available.

Transition dairy cows are vulnerable to negative consequences of depressed feed intake due to a transient state of negative energy balance that predisposes them to disease after calving. Competition has been identified as one factor that can decrease feeding activity in mid-lactation cows, but the effects of competition on the transition cow are less well understood. The objective of this study was to test the effect of a competition on the behaviour and feed intake of transition cows. Standing behaviour, feeding behaviour and dry matter intake (DMI) was monitored from 1 wk before to 2 wk after calving for 110 Holstein dairy cows. Social behaviour was recorded in the week before calving. Cows were assigned to a competitive (2:1 cows:bin) or non-competitive (1:1 cow:bin) treatment at the start of the study. Treatment groups were balanced for parity and baseline feeding data, resulting in 8 primiparous and 10 multiparous cows per treatment. Competition dramatically increased the number of agonistic behaviours between cows at the feeder. Primiparous cows showed no change in either feeding or standing behaviour when fed in a competitive environment; however, they increased their total meal duration and within-meal intervals in the wk -1 before and wk +1 after calving. In wk -1 before calving, competitively fed multiparous cows increased the frequency of visits to the feeder but consumed less feed at each visit, resulting in decreased daily DMI. Throughout the experiment, multiparous cows fed competitively spent less time eating at each visit and ate at a faster rate, particularly during the 2 wk after calving. Multiparous cows on the competitive treatment also increased the time they spent standing (without eating) compared to cows on the non-competitive treatment. Feeding rate was negatively correlated with social status in multiparous cows. In summary, the results of this study indicate that restricting access to the feeder increases agonistic behaviours regardless of parity, and cows of different parity and social status respond differently in terms of feeding and standing behaviour. / Land and Food Systems, Faculty of / Graduate

No description available.

Calving is an essential event in dairy production, as lactation only begins after calving and cows must give birth at regular intervals in order to maintain milk production. Careful management is important during the weeks around calving as this is when dairy cows most frequently experience health problems. Experienced stockmen use judgements based on physical and behavioural changes in order to recognise when cows may be about to calve, and subsequently be available to offer assistance when required. With increasing herd sizes and large numbers of cows per stockman, individual attention is often difficult. An automated system that monitors behavioural or physiological changes before calving could potentially be used to predict the time of calving, and help improve supervision by farm staff. Data comprising two years of records from Langhill Farm were used to identify any variables which could be used for calving prediction or as risk factors for various calving problems. Records kept by stockmen detailing the signs of calving and time of observation were compared with quantitative behavioural data. Observations from video recordings were used to identify any consistent behavioural changes occurring the day before calving that could be used to predict the onset of calving. The frequencies of lying and tail raises proved to be the most useful indicators, as they showed consistent changes in the final six hours before calving. Differences between heifers and cows, and between those experiencing calving difficulties and those which did not, were also investigated. Differences between heifers and cows were shown which should be taken into account when predicting calving times. However, no early-warning signs of difficulties were identified for cows and heifers assisted with a calving jack. Cows were also fitted with collars containing accelerometers to investigate if features in tri-axial accelerometer data could be shown to correspond to specific behaviours. Some success was achieved in identifying eating behaviour and postural changes, demonstrating that there is potential for monitoring behaviour using this method. Weekly heart rate recordings were also taken to establish if there was a change in the heart rate or heart rate variability during the final six weeks of gestation. Changes were found but, although they were statistically significant, they were considered too subtle for any practical application. Consistent changes in behaviour were observed in the six hours before calving, some of which could be measured using accelerometers. These changes have the potential to be used as the basis of an automated monitoring system to predict calving.

Dairy cattle make a significant contribution to global methane emissions. Milking cows in the UK make up about a fifth of the total cattle population, with Holstein-Friesian cows being the most common breed. Investigating ways to minimise methane, a potent greenhouse gas (GHG) produced by dairy cows from enteric fermentation and manure, has gained importance in recent years due its role in climate change. Currently, GHG emissions from UK dairy farming are predicted using the Intergovernmental Panel on Climate Change (IPCC) Tier II methodology. The IPCC Tier II methodology and statistical prediction equations from the literature were evaluated for their ability to reliably model methane output using data from the Langhill Holstein-Friesian experimental herd. The Langhill dairy herd is on a long-term breeding and feeding systems experiment, and cows are on average 88% North American Holstein genes. The production systems within the herd represent a range of dairy systems that may be found commercially. Therefore, production values were assumed to be representative of those that could be found in the commercial Holstein-Friesian population, so factors affecting system methane emissions and appropriate mitigation options could be investigated. Prediction equations using dry matter (DM) intake and gross energy intake as input values were the most appropriate equations for reliably estimating daily enteric methane output. However, if DM intake values are not available, the IPCC Tier II method was found to provide a suitable prediction of methane emissions over a cow‘s lactation and lifetime. This study found that GHG emissions from enteric fermentation and manure, expressed as carbon dioxide equivalents (CO2-eq.), account for about 66% of dairy system CO2-eq. emissions, with enteric methane output being the main contributor (34% of system CO2-eq. emissions). Breeding for increased kilograms of milk fat plus protein production was shown to help reduce dairy system methane emissions. Cows of predominantly North American Holstein genes in this study produced more milk when fed a diet with a low proportion of forage and had lower GHG emissions and land requirement per kilogram energy corrected milk than similar cows fed a diet with a higher proportion of forage. Strategies to mitigate GHG emissions (including methane) and the environmental impact of dairy systems should seek to select animals that better utilise their feed intake to meet their genetic potential for milk production.