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40 BC HOLSTEIN NEWS a FALL 2020 Vet Focus
 Avoid Disrupting Transition Cows
 To Move? Or When to Move?
 By Dr. Christina Lyn, DVM, Greenbelt Veterinary Services
In today’s typical freestall housing system, cows are moved multiple times throughout their lactation to facilitate better management and care, based on production, lactation, and other special needs. For lactating cows, the potential benefits of improved management and milk production outweigh the relatively small cost of social stress, and the associated temporary drop in dry matter intake (DMI) and milk production (von Keyserlingk et al., 2008). For the vulnerable transition cow however, the moves may be less benign, and have more significant consequences. The question then is: when is the best time to move a cow to the calving pen?
This primes cows (especially dominant cows) for subacute ruminal acidosis. It increases the risk of lameness among subordinate cows due to the decreased lying times, and often increased time spent waiting in the alley for their turn at the feed bunk (Hosseinkhani et al., 2008; Proudfoot et al., 2009). Huzzey et al. found that cows with a lower DMI prepartum were more likely to be diagnosed with metritis postpartum. This was the first study to highlight a relationship between the social behaviour of cows and disease risk.
So how do the different dry cow management strategies compare?
Avoiding crowding is especially important for minimizing social stress on transition cows.
     STRATEGY
DESCRIPTION
WHY IT REDUCES SOCIAL STRESS
ADVANTAGES
         All-in All-out
Maintain a stable dry cow group through to calving
Forms a stable hierarchy with no introduction or removal of animals
• REMOVES ALL PEN CHANGES DURING THE TRANSITION PERIOD
• Increased rates of mis-mothering • Pens are generally not cleaned out
between calvings
• Challenging to achieve consistent groups
      Short stay maternity pens
Long stay maternity pens
Just in time calving
Dry cows are moved into maternity pen 2 days before calving
Dry cows are moved to a maternity pen 7-14 days before calving
Cows are moved when they enter stage 2 of labour
Cows that are within
2 days of calving are thought to avoid social contact
Gives cows enough time to establish a new hierarchy prior to when they naturally reduce their DMI prior to calving
Little disruption prior to calving
Disadvantages
• Requires skill and knowledge to be able to estimate when a cow is within 2 days of calving
• CAN MOVE A GROUP OF ANIMALS ONCE A WEEK
• Requires enough space to accommodate each group
• CALVES ARE USUALLY DEALT WITH PROMPTLY
thatarewithintwodaysof calvingtendtoavoidsocial contact. It requires your herdsperson to be very skilled and knowledgeable in estimating when a cow is within two days of calving. Long stay maternity pens can be used to move a group of dry cows once a week if they are within 7-14 days of calving. This approach requires enough maternity pens to accommodate each group until they calve. This gives the cows enough time to establish a hierarchy without impacting their intakes and lying behaviour close to calving.
not move cows 2-7 days before calving to prevent a further reduction of DMI before calving. Short stay maternity pens are thought to reduce stress because cows
calving behaviour (Proudfoot et al., 2013). This is detrimental to the cow and calf, as cows need to lie down to exert maximum abdominal pressure, and second stage labour lasting longer than 120 minutes significantly increases calf perinatal mortality (Gundelach et al., 2009). With thisinmind,“justintimecalving”describes moving cows at the start of stage 2 labour. This causes the least disruption to the cow prior to being moved to a calving pen. Consequently, they are more likely to maintain their DMI, and calving is not delayed (Atkinson, 2016). To be done correctly, there must be 24/7 monitoring of the maternity pens so that cows are moved at the appropriate time, which ensures that the negative consequences of moving a cow too early are avoided. This constant monitoring also has the added benefit that calves are often removed and fed colostrum quickly (Atkinson, 2016).
When considering the different management techniques, one is not inherently better than the other. The best management strategy will be the one that is most practical for your farm having regard to the labour, space, and the number of cows. The key takeaways are to not move cows 2-7 days before calving, or in stage 1 of labour. Other things you can do to ensure your cows are experiencing the least amount of social and metabolic stress include: maintaining a stocking density of 85% or less, evaluate their access to the feed bunk, if possible do not co-mingle heifers and multiparous cows, and moving cows at appropriate times, ideally in small groups and later in the day to avoid feeding times. We expect a lot from our cows; being cognizant of their social stress is an easy way for us to help them transition better into the herd.
References available upon request.
          Nordlund’s 2006 research established: 1) cows have a dominance hierarchy, strongly associated with age, body size, and seniority in a herd; 2) they are allelomimetic, meaning they like to perform the same activity or behaviour (like eating) as a group; 3) on average, it takes anywhere from 2-7 days for a group to stabilize following the introduction of a new animal. The hierarchy is established through non-physical and physical interactions such as displacements, threats, and butting (von Keyserlingk et al., 2008). These interactions are most notable at the feed bunk, and have been shown to cause multiparous dry cows to:
1 - Further reduce their DMI
2 - Increase their feeding rate
3 - Consume fewer but longer meals per day 4 - Have increased standing time and
(Proudfoot et al., 2009; Hosseinkhani et al. 2008).
1. All-in All-out
For very large herds it may be possible to keep stable dry cow groups through to calving; effectively getting rid of any movements close to calving. Potential problems with this management style include: mis-mothering, calves suffering trauma, and reduced hygiene because the pens are not cleaned out between calvings. Even for very large farms it can be challenging to achieve consistent groups that are large enough for this “All-in/All-out” method.
2. Short Stay and Long Stay
Maternity Pens
Short stay and long stay maternity pens have been adopted by many farms (Nordlund et al., 2006). The key here is to
3. Just in Time Calving
The last common approach is “just in time calving”. Labour has three defined stages:
Stage 1) the cow begins to raise her tail and change positions, the cervix begins to dilate, and the calf moves into position,
Stage 2) starts when the water breaks and ends when the calf is expelled,
Stage 3) describes the expulsion of the placenta and uterine involution (Proudfoot et al., 2013).
A study found that cows who were moved to an individual pen during late stage 1 (defined as the appearance of viscous bloody mucus and/or first contractions) attracted more attention from other cows, the cow spent less time lying down, and experienced a longer duration of stage 2 possibly due to the disruption of the normal
therefore decreased lying time
• Requires 24/7 monitoring
  BC Appoints New Chief Veterinarian
 BC’s Minister of Agriculture Lana Popham has appointed Dr. Rayna Gunvaldsen as the new chief veterinarian for British Columbia effective June 2020.
Dr. Gunvaldsen holds a Doctor of Veterinary Medicine degree from the University of Saskatchewan with an emphasis in herd health and regulatory medicine. She also holds a bachelor’s degree in agriculture and a Master of Science in veterinary medicine focusing on large animal clinical sciences and swine influenza. Dr. Gunvaldsen has worked on disease outbreaks throughout Western Canada, including Chronic Wasting Disease, Bovine Tuberculosis, and Salmonella, and is trained in emergency preparedness and management.
Originally from Saskatchewan, Dr. Gunvaldsen began
herveterinarycareerasaswineveterinarianproviding herd health services to pig producers. After completing her Masters, Dr. Gunvaldsen joined the Canadian Food Inspection Agency (CFIA) as the Foreign Animal Disease Veterinarian for Saskatchewan and continued to work in various positions with the CFIA and the Government of Alberta.
The chief veterinarian supports the sustainability of animal agriculture in BC through the development and implementation of sound livestock health and regulatory management policies. Based at the BC Animal Health Centre in Abbotsford, Dr. Gunvaldsen is assuming the role from Dr. Jane Pritchard, who recently retired after serving as BC’s chief veterinary officer since 2013.
Dr. Rayna Gunvaldsen is BC’s New Chief Veterinarian, as of June.
  


































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