Tue, Jan 17 2012 02:25
Farm First Newsletter January 2012
ARE COWS THIN BECAUSE THEY ARE LAME, OR LAME BECAUSE THEY ARE THIN?
So which do you think is correct?! A recently reported study by Bicalho and colleagues from Cornell used ultrasound to measure the thickness of the digital cushion, which is the pad of fat between the pedal bone above and the horn of the sole below.
They scanned 500 cows and found at high correlation between
1. the fat pad thickness and the presence of sole ulcers and white line abscesses (thin fat pad gave more disease)
2. fat pad thickness and body condition score – thin cows had thinner fat pads
3. fat pad thickness and stage of lactation. By 120 days the fat pad was at its thinnest (as were most cows) and hoof lameness at its highest.
This does not mean that changes around calving are no longer thought to be important. The poorer suspension (and subsequent increased movement) of the pedal bone inside the hoof just before and just after calving increases the risk of coriosis and this leads to the subsequent production of defective horn. A thinner fat pad exacerbates these effects.
Conclusions – take extra care over the comfort of your cows around calving (and yes, thin cows get more lameness!). We at last seem to be getting away from the obsession by some that lameness is primarily a dietary problem (although it is accepted that acidosis can lead to low biotin and subsequently increased lameness). In fact the authors concluded that diet can at most be only a contributory factor in most herds, although they did acknowledge that high yielding cows would lose more weight, lose more thickness of the fat pad and then develop more lamenesss.
Use of Elastrator Rings in Calves
Recent submissions to AHVLA regional laboratories indicate that the illegal practice of applying rubber elastrator rings to the scrotum, particularly of purchased, entire calves aged over seven days, is occurring. Legislation prohibits the application of a rubber ring or other device to constrict the flow of blood to the scrotum of cattle older than seven days of age. The Veterinary Surgeons Act (1966) allows persons over the age of 18 (17 for supervised animal husbandry students) to carry out castrations on calves less than two months of age using for example a burdizzo. Only a veterinary surgeon can carry out castrations in calves over two months of age and an anaesthetic must be used. In all cases the procedure used must minimise the pain and suffering to the animal, be performed in good hygiene conditions, and in accordance with best practice.
In addition to the practice being illegal, it is likely that the calves which had the elastrator rings applied at greater than seven days of age would have been subjected to prolonged discomfort which would have reduced growth rates, and increased their susceptibility to disease.
New bovine and ovine illness in Germany and Holland
What appears to be a new virus has been discovered in the North Rhein Westphalia district of the west of Germany, and in Holland. It has been named Schmallenberg virus after the small town where it was first discovered.The virus was originally seen in cattle, from August to October, when it caused a moderate fever, with temperatures up to 40 degrees centigrade, inappetance, loss of condition, diarrhoea in some cases, and a drop in milk yield of up to 50%. All the cattle recovered, BUT there is a considerable sting in the tale in that in the last few weeks, many of the affected cattle have either aborted, or had stillborn calves. Typically these calves have limb deformities, stiff limbs, crooked necks, sometimes a twisted spine, or hydrocephalus. Numerous calves born alive to affected cows have failed to live longer than a day or two. They have severe brain damage and appear to be “Dummies”, which are unable to suck.
At the same time, there have been numerous reports of similarly deformed lambs being born, mainly in Holland, again put down to Schmallenberg disease. Research is at a very early stage and the virus has yet to be isolated, but DNA sequencing shows it to be an orthobunyavirus. In Australia, the best known of these viruses is spread by midges, but it is yet to be shown whether this will happen in this case.
If you have any lambs or calves born with these typical deformities, AHVLA are interested in sampling affected animals. Equally, if you're experiencing unusually high levels of abortion in either cattle or sheep please contact us to discuss how we should investigate, for either this or more common causes of the problem.Meetings
Farming Connect are sponsoring a meeting to be held on 19 January at 7:30 pm. Subject of the evening's discussions is “Lameness in sheep, the causes, treatment and prevention”. Please contact us nearer the time for details of the venue.
Anyway hope you all had a good Xmas and wishing you all a prosperous 2012!
ARE COWS THIN BECAUSE THEY ARE LAME, OR LAME BECAUSE THEY ARE THIN?
So which do you think is correct?! A recently reported study by Bicalho and colleagues from Cornell used ultrasound to measure the thickness of the digital cushion, which is the pad of fat between the pedal bone above and the horn of the sole below.
They scanned 500 cows and found at high correlation between
1. the fat pad thickness and the presence of sole ulcers and white line abscesses (thin fat pad gave more disease)
2. fat pad thickness and body condition score – thin cows had thinner fat pads
3. fat pad thickness and stage of lactation. By 120 days the fat pad was at its thinnest (as were most cows) and hoof lameness at its highest.
This does not mean that changes around calving are no longer thought to be important. The poorer suspension (and subsequent increased movement) of the pedal bone inside the hoof just before and just after calving increases the risk of coriosis and this leads to the subsequent production of defective horn. A thinner fat pad exacerbates these effects.
Conclusions – take extra care over the comfort of your cows around calving (and yes, thin cows get more lameness!). We at last seem to be getting away from the obsession by some that lameness is primarily a dietary problem (although it is accepted that acidosis can lead to low biotin and subsequently increased lameness). In fact the authors concluded that diet can at most be only a contributory factor in most herds, although they did acknowledge that high yielding cows would lose more weight, lose more thickness of the fat pad and then develop more lamenesss.
Use of Elastrator Rings in Calves
Recent submissions to AHVLA regional laboratories indicate that the illegal practice of applying rubber elastrator rings to the scrotum, particularly of purchased, entire calves aged over seven days, is occurring. Legislation prohibits the application of a rubber ring or other device to constrict the flow of blood to the scrotum of cattle older than seven days of age. The Veterinary Surgeons Act (1966) allows persons over the age of 18 (17 for supervised animal husbandry students) to carry out castrations on calves less than two months of age using for example a burdizzo. Only a veterinary surgeon can carry out castrations in calves over two months of age and an anaesthetic must be used. In all cases the procedure used must minimise the pain and suffering to the animal, be performed in good hygiene conditions, and in accordance with best practice.
In addition to the practice being illegal, it is likely that the calves which had the elastrator rings applied at greater than seven days of age would have been subjected to prolonged discomfort which would have reduced growth rates, and increased their susceptibility to disease.
New bovine and ovine illness in Germany and Holland
What appears to be a new virus has been discovered in the North Rhein Westphalia district of the west of Germany, and in Holland. It has been named Schmallenberg virus after the small town where it was first discovered.The virus was originally seen in cattle, from August to October, when it caused a moderate fever, with temperatures up to 40 degrees centigrade, inappetance, loss of condition, diarrhoea in some cases, and a drop in milk yield of up to 50%. All the cattle recovered, BUT there is a considerable sting in the tale in that in the last few weeks, many of the affected cattle have either aborted, or had stillborn calves. Typically these calves have limb deformities, stiff limbs, crooked necks, sometimes a twisted spine, or hydrocephalus. Numerous calves born alive to affected cows have failed to live longer than a day or two. They have severe brain damage and appear to be “Dummies”, which are unable to suck.
At the same time, there have been numerous reports of similarly deformed lambs being born, mainly in Holland, again put down to Schmallenberg disease. Research is at a very early stage and the virus has yet to be isolated, but DNA sequencing shows it to be an orthobunyavirus. In Australia, the best known of these viruses is spread by midges, but it is yet to be shown whether this will happen in this case.
If you have any lambs or calves born with these typical deformities, AHVLA are interested in sampling affected animals. Equally, if you're experiencing unusually high levels of abortion in either cattle or sheep please contact us to discuss how we should investigate, for either this or more common causes of the problem.Meetings
Farming Connect are sponsoring a meeting to be held on 19 January at 7:30 pm. Subject of the evening's discussions is “Lameness in sheep, the causes, treatment and prevention”. Please contact us nearer the time for details of the venue.
Anyway hope you all had a good Xmas and wishing you all a prosperous 2012!
Mon, Dec 5 2011 06:46
Farm First Newsletter December 2011
Conception Rates in the Dairy Herd
Conception rates (CR) in dairy cows have fallen from 50% to 25% over the past 25 years. Factors which affect CR include bull fertility, accuracy of heat detection (a cow served at the wrong time will not conceive), and semen handling. Research has shown that 90% of cows served correctly when on heat will be carrying a live embryo 7 days later, but approx. 55% of these will subsequently die. If this occurs at day 6-16 it is seen as a return to heat, after this it will be seen as an irregular heat or an abortion. So, as early embryonic death is a major cause of the low conception rates we currently see, what can we do about it? We know that low progesterone levels are associated with embryo loss by several mechanisms, so we need to manage cows in ways to keep their progesterone levels high. Liver blood flow in lactating cows is 40% higher than in dry cows, and it rises by a further 20-30% after feeding. As more blood filters through the liver, blood progesterone levels fall by 30%. If the feeding interval is extended or extra large meals are fed there will be an even greater rise in liver blood flow, and fall in blood progesterone, reducing the likelihood of producing and maintaining viable embryos.
To avoid a negative effect on progesterone concentration cows should eat a meal every 2 to 2½ hours or 10 meals a day, each comprising of 2 to 2.5kg of DM. This requires good levels of cow comfort to allow the cow to express normal patterns of behaviour. This means adequate nutrition, feed access, ventilation, light, water, feed push-ups, good mobility, correct stocking density and only short periods away for milking (1hour).Patterns of cow behaviour are established early in lactation, so good transition cow management is vital.
Mobility Scoring
Many of our dairy clients have contracts with their milk buyers which require them to have Locomotion Scoring done by an independent person. We can now offer you this service at a cost of £35 per hour (+visit), and it will be carried out by Simeon or Ferenc, our TB testing vets. A summary report will be provided following the visit. The scoring can be carried out at an afternoon milking, when the vet will want to see all the cows on their way into, or out of the collecting yard or milking parlour. If you are interested in this service please ring us to discuss a suitable time and date.
Agger’s Proliver – Treatment for Fatty Liver Disease
We have a new product on the shelf designed for the prevention and treatment of Fatty Liver Disease. This is commonly seen in dairy cows, usually within a week of calving, when too much fat has accumulated in the liver. This impairs liver function and these cows lose condition rapidly and may be unresponsive to treatment of other diseases. It is often seen in “runs”. Agger’s Pro-liver contains mono-propylene glycol as an energy source, vitamins, enzymes and minerals which support liver function, promote fluid intake and provide energy. The product comes as a drench and costs £7.14 +vat per bottle. The suggested protocol is 1 bottle every 12 hours for 4 days, for 2 days before calving, to 2 days after calving. If handling is an issue, 1 bottle administered every 12 hrs for 2 days will significantly benefit the cow. For cows with Fatty Liver disease one bottle should be given every 12 hours along with half a bottle of Agger’s Glycerol.
Kling on Blue – Long Acting Footbath for Sheep
This is now available in an easy-to-mix form which is ready in minutes. The product contains copper sulphate, zinc sulphate and organic acid in thick solution which sticks to the foot, and gives increased zinc penetration to the hoof. It is effective in the control of scald, footrot and CODD. As the solution sticks to the foot, sheep only need to be bathed once for scald, 1-3 times for footrot, and once weekly for CODD, for a minimum of 3 times. Good footbathing facilities are required for any treatment to work well. Ideally sheep should walk through a bath of clean water first. One 7kg bucket costs £60 + vat will mix into 120 litres of footbath, and is sufficient to treat 250 sheep once. The costs drops to £55+ vat if 2 or more buckets are purchased at once.
Closamectin Pour-On
Although we do not often promote the use of combination products (a targeted approach to parasite control is better), this is the time of year when there is a place for this combined flukicide and wormer. The closantel in it will kill adult fluke and immature fluke from 7 weeks of age, and the ivermectin is effective against most worms, lice and mange. Beef cattle can be treated at housing, but may need a second dose if housed early, or if pasture contamination is high. If outwintered, a treatment should be given in late autumn and possibly repeated in early January. The withdrawal time is 28 days for meat, and it can be used in dairy cattle which are more than 60 days away from calving.
Farming Connect Meetings
We have been approached by Farming Connect to give a series of talks at meetings in this area. The first of these is on the topical subject of “Pneumonia in Cattle –Causes, Control and Prevention”, and will be held at Alice Springs Golf Club on 8th December at 7.30 pm. The subject of the following one will be “Lameness in Sheep”, to be held on 18th January.
Merry Christmas
Finally, we would like to wish you a Merry Christmas and a Happy New Year. The opening times over the holiday season are as follows:”
Friday 23rd December- office closes 1pm.
Monday 26th December – office closed.
Tuesday 27th December – office closed.
Wednesday 28th and Thursday 29th - normal office hours
Friday 29th December – office closes 1 pm.
Monday 2nd January – office closed.
Tuesday 3rd January – normal opening hours resume.
During the holiday period we will of course provide our normal 24 hour emergency cover. If you require drugs urgently (that is veterinary drugs!) during the holiday period please ring the emergency number and the duty vet will arrange for them to be dispensed.
Conception Rates in the Dairy Herd
Conception rates (CR) in dairy cows have fallen from 50% to 25% over the past 25 years. Factors which affect CR include bull fertility, accuracy of heat detection (a cow served at the wrong time will not conceive), and semen handling. Research has shown that 90% of cows served correctly when on heat will be carrying a live embryo 7 days later, but approx. 55% of these will subsequently die. If this occurs at day 6-16 it is seen as a return to heat, after this it will be seen as an irregular heat or an abortion. So, as early embryonic death is a major cause of the low conception rates we currently see, what can we do about it? We know that low progesterone levels are associated with embryo loss by several mechanisms, so we need to manage cows in ways to keep their progesterone levels high. Liver blood flow in lactating cows is 40% higher than in dry cows, and it rises by a further 20-30% after feeding. As more blood filters through the liver, blood progesterone levels fall by 30%. If the feeding interval is extended or extra large meals are fed there will be an even greater rise in liver blood flow, and fall in blood progesterone, reducing the likelihood of producing and maintaining viable embryos.
To avoid a negative effect on progesterone concentration cows should eat a meal every 2 to 2½ hours or 10 meals a day, each comprising of 2 to 2.5kg of DM. This requires good levels of cow comfort to allow the cow to express normal patterns of behaviour. This means adequate nutrition, feed access, ventilation, light, water, feed push-ups, good mobility, correct stocking density and only short periods away for milking (1hour).Patterns of cow behaviour are established early in lactation, so good transition cow management is vital.
Mobility Scoring
Many of our dairy clients have contracts with their milk buyers which require them to have Locomotion Scoring done by an independent person. We can now offer you this service at a cost of £35 per hour (+visit), and it will be carried out by Simeon or Ferenc, our TB testing vets. A summary report will be provided following the visit. The scoring can be carried out at an afternoon milking, when the vet will want to see all the cows on their way into, or out of the collecting yard or milking parlour. If you are interested in this service please ring us to discuss a suitable time and date.
Agger’s Proliver – Treatment for Fatty Liver Disease
We have a new product on the shelf designed for the prevention and treatment of Fatty Liver Disease. This is commonly seen in dairy cows, usually within a week of calving, when too much fat has accumulated in the liver. This impairs liver function and these cows lose condition rapidly and may be unresponsive to treatment of other diseases. It is often seen in “runs”. Agger’s Pro-liver contains mono-propylene glycol as an energy source, vitamins, enzymes and minerals which support liver function, promote fluid intake and provide energy. The product comes as a drench and costs £7.14 +vat per bottle. The suggested protocol is 1 bottle every 12 hours for 4 days, for 2 days before calving, to 2 days after calving. If handling is an issue, 1 bottle administered every 12 hrs for 2 days will significantly benefit the cow. For cows with Fatty Liver disease one bottle should be given every 12 hours along with half a bottle of Agger’s Glycerol.
Kling on Blue – Long Acting Footbath for Sheep
This is now available in an easy-to-mix form which is ready in minutes. The product contains copper sulphate, zinc sulphate and organic acid in thick solution which sticks to the foot, and gives increased zinc penetration to the hoof. It is effective in the control of scald, footrot and CODD. As the solution sticks to the foot, sheep only need to be bathed once for scald, 1-3 times for footrot, and once weekly for CODD, for a minimum of 3 times. Good footbathing facilities are required for any treatment to work well. Ideally sheep should walk through a bath of clean water first. One 7kg bucket costs £60 + vat will mix into 120 litres of footbath, and is sufficient to treat 250 sheep once. The costs drops to £55+ vat if 2 or more buckets are purchased at once.
Closamectin Pour-On
Although we do not often promote the use of combination products (a targeted approach to parasite control is better), this is the time of year when there is a place for this combined flukicide and wormer. The closantel in it will kill adult fluke and immature fluke from 7 weeks of age, and the ivermectin is effective against most worms, lice and mange. Beef cattle can be treated at housing, but may need a second dose if housed early, or if pasture contamination is high. If outwintered, a treatment should be given in late autumn and possibly repeated in early January. The withdrawal time is 28 days for meat, and it can be used in dairy cattle which are more than 60 days away from calving.
Farming Connect Meetings
We have been approached by Farming Connect to give a series of talks at meetings in this area. The first of these is on the topical subject of “Pneumonia in Cattle –Causes, Control and Prevention”, and will be held at Alice Springs Golf Club on 8th December at 7.30 pm. The subject of the following one will be “Lameness in Sheep”, to be held on 18th January.
Merry Christmas
Finally, we would like to wish you a Merry Christmas and a Happy New Year. The opening times over the holiday season are as follows:”
Friday 23rd December- office closes 1pm.
Monday 26th December – office closed.
Tuesday 27th December – office closed.
Wednesday 28th and Thursday 29th - normal office hours
Friday 29th December – office closes 1 pm.
Monday 2nd January – office closed.
Tuesday 3rd January – normal opening hours resume.
During the holiday period we will of course provide our normal 24 hour emergency cover. If you require drugs urgently (that is veterinary drugs!) during the holiday period please ring the emergency number and the duty vet will arrange for them to be dispensed.