I had a thread awhile back asking about maternal instincts in heifers and the ones that attack their calves. I was mostly looking at what's different between people without problems, and ones that have a lot of problems with their heifers. After evaluating the survey folks did, and talking with some producers, veterinarians, a behavioralist and reading some research articles.... here's what I got out of it.
>Most of the studies are 1970-1990; apparently cattle maternal behavior isn't very interesting.
>Very, *very* few articles refer to heifers attacking their *own* calf. Cows/heifers attacking the producer is common, and heifers that display disinterest or walk away from the calf, is also common.
>Per the survey, most everyone says 1-5% of their animals. No correlation between behavior and location of the U.S. or calving location (eg barn, grass, calving lot). There may have been some correlation between behavior and use of calving ease sires - but - it may also be that most people use CE bulls and I didn't have many responses without CE bulls. The two things that did stand out is that most people check their heifers less frequently (every couple hours) than the operation with a 30% incidence of heifer problems (every hour around the clock). Also, most people won't tolerate those heifers, and cull them. 50% would cull the calves too.
>In literature, heifers displaying some level of aggressive behavior approached 13-16%. One thing researchers noted was that heifers often seemed afraid of their calves (eg keeping the calf at their head) and aggression was more likely when the pair were confined in a space where the heifer couldn't escape from the calf. (I realize people in research sometimes study some inane things or at least have bizarre ways of explaining what they're studying- bear with me here.)
>One DVM clinician said he's encountered it more in Angus heifers than other breeds (said it's a known trait) - I didn't run across literature to support that, but I realize personal observations don't always make it into published literature either.
>A PhD behavioralist said that in general, mothering behavior is influenced by the environment/situation at parturition and by exposure to older females with offspring. (While interesting, I wouldn't advise running replacements with mature cows to teach them how to be good mothers! Sounds like a disease transmission nightmare.)
>A study of Canadian producers found that ranchers felt mothering behavior was situational and aggression toward the producer was genetic. (Oddly in light of their opinions, producers tended to keep the aggressive cows and cull the poor mothers.)
This particular operation brings the heifer herd in by the barn at night so they can be checked hourly. The herd has occasional contact with people up to that point, and bringing the heifers into a corral begins when calving season starts.
>Literature supports the theory that mothering behavior is related to the situation, eg being brought into the barn away from the herd at calving. (But, that doesn't explain heifers who calve alone/undisturbed on pasture and attack their calves.)
>Stress/new situations related to going into the barn to calve - or perhaps the entire herd being moved and locked up nightly - may play a part in undesirable mothering behavior.
>It is possible this place has a higher incidence of "over mothering" than other producers because they have some real nice facilities and are set up to effectively deal with those heifers - and they don't get culled.
>It is possible that the place has indirectly selected for heifers with undesirable behavior. Most operations (per CT, Ranchers, and a few people interviewed in person) don't keep heifers that attack their calves- but the place with a 30% incidence does. If records of the herd support this at all, the easiest way to solve the problem would be to tag every heifer with a disposition score over X value, *and* tag her heifer calf, and cull both of them in the fall. If this can't be supported, then environmental causes should be considered.
>It is also possible that locking the herd up at night -and checking hourly in a herd that's infrequently seen people before calving- causes enough stress to heifers that they display undesirable mothering behavior when they calve. If there is a decrease in heifers that attack their calves at the end of calving season as compared to the beginning, that could support the theory, as heifers calving at the end of the season have had a month to become acclimated to the daily routine. If this is the case, the heifers might benefit from more exposure to people/horses prior to calving to decrease stress. (And there- an individual operation would have to decide if the time spent desensitizing the heifers prior to calving is less than the work it would take to deal with the heifers that attack their calves.)
Lastly, the behavioralist said oxytocin helps in the bonding process of cow/calf, and there's some indication that an intranasal whiff of oxytocin can cross the blood-brain-barrier and stimulate appropriate maternal behavior in cattle. IM injection of oxytocin does not cross the BBB (it's a large molecule). So there's a possibility for dealing with a crazy heifer after calving.
Thought y'all would like an update. I don't have information on herd records to indicate if the place with a 30% incidence is looking at a situational problem or a genetic problem- might acquire that data someday but I don't have it now. However, I found the topic interesting and had fun thinking through it. No real conclusions on the matter but just some thoughts on why it might occur. Feel free to comment if any of the rest of you have ideas.
>Most of the studies are 1970-1990; apparently cattle maternal behavior isn't very interesting.
>Very, *very* few articles refer to heifers attacking their *own* calf. Cows/heifers attacking the producer is common, and heifers that display disinterest or walk away from the calf, is also common.
>Per the survey, most everyone says 1-5% of their animals. No correlation between behavior and location of the U.S. or calving location (eg barn, grass, calving lot). There may have been some correlation between behavior and use of calving ease sires - but - it may also be that most people use CE bulls and I didn't have many responses without CE bulls. The two things that did stand out is that most people check their heifers less frequently (every couple hours) than the operation with a 30% incidence of heifer problems (every hour around the clock). Also, most people won't tolerate those heifers, and cull them. 50% would cull the calves too.
>In literature, heifers displaying some level of aggressive behavior approached 13-16%. One thing researchers noted was that heifers often seemed afraid of their calves (eg keeping the calf at their head) and aggression was more likely when the pair were confined in a space where the heifer couldn't escape from the calf. (I realize people in research sometimes study some inane things or at least have bizarre ways of explaining what they're studying- bear with me here.)
>One DVM clinician said he's encountered it more in Angus heifers than other breeds (said it's a known trait) - I didn't run across literature to support that, but I realize personal observations don't always make it into published literature either.
>A PhD behavioralist said that in general, mothering behavior is influenced by the environment/situation at parturition and by exposure to older females with offspring. (While interesting, I wouldn't advise running replacements with mature cows to teach them how to be good mothers! Sounds like a disease transmission nightmare.)
>A study of Canadian producers found that ranchers felt mothering behavior was situational and aggression toward the producer was genetic. (Oddly in light of their opinions, producers tended to keep the aggressive cows and cull the poor mothers.)
This particular operation brings the heifer herd in by the barn at night so they can be checked hourly. The herd has occasional contact with people up to that point, and bringing the heifers into a corral begins when calving season starts.
>Literature supports the theory that mothering behavior is related to the situation, eg being brought into the barn away from the herd at calving. (But, that doesn't explain heifers who calve alone/undisturbed on pasture and attack their calves.)
>Stress/new situations related to going into the barn to calve - or perhaps the entire herd being moved and locked up nightly - may play a part in undesirable mothering behavior.
>It is possible this place has a higher incidence of "over mothering" than other producers because they have some real nice facilities and are set up to effectively deal with those heifers - and they don't get culled.
>It is possible that the place has indirectly selected for heifers with undesirable behavior. Most operations (per CT, Ranchers, and a few people interviewed in person) don't keep heifers that attack their calves- but the place with a 30% incidence does. If records of the herd support this at all, the easiest way to solve the problem would be to tag every heifer with a disposition score over X value, *and* tag her heifer calf, and cull both of them in the fall. If this can't be supported, then environmental causes should be considered.
>It is also possible that locking the herd up at night -and checking hourly in a herd that's infrequently seen people before calving- causes enough stress to heifers that they display undesirable mothering behavior when they calve. If there is a decrease in heifers that attack their calves at the end of calving season as compared to the beginning, that could support the theory, as heifers calving at the end of the season have had a month to become acclimated to the daily routine. If this is the case, the heifers might benefit from more exposure to people/horses prior to calving to decrease stress. (And there- an individual operation would have to decide if the time spent desensitizing the heifers prior to calving is less than the work it would take to deal with the heifers that attack their calves.)
Lastly, the behavioralist said oxytocin helps in the bonding process of cow/calf, and there's some indication that an intranasal whiff of oxytocin can cross the blood-brain-barrier and stimulate appropriate maternal behavior in cattle. IM injection of oxytocin does not cross the BBB (it's a large molecule). So there's a possibility for dealing with a crazy heifer after calving.
Thought y'all would like an update. I don't have information on herd records to indicate if the place with a 30% incidence is looking at a situational problem or a genetic problem- might acquire that data someday but I don't have it now. However, I found the topic interesting and had fun thinking through it. No real conclusions on the matter but just some thoughts on why it might occur. Feel free to comment if any of the rest of you have ideas.
