07/16/17
Litter Size - Can we predict it?

Litter Size – What the research says

Litter Size - Can we predict it?

There is an ongoing paucity in the literature surrounding most dog matters, and that means dog knowledge is often based on anecdotes and experience instead of facts and figures. Dog breeding is no exception. Breeders will tell you that they get bigger litters if x, smaller litters if y, that they’ll never mate a bitch if z. While personal experiences can provide case studies, I am interested in much bigger data.

Enter a Norwegian study looking at 10,810 litters.

This study used data held by the Norwegian Kennel Club to look at every litter registered in 2006 and 2007, across 224 breeds. Statistical analysis was then done to determine all the wonderful figures summarised below.

The aim of this study was to determine what actually makes a difference in litter size. (Litter size being the number of puppies born, alive or dead.)

Firstly, an overall average had to be determined. For this data set, the average litter size, considering all breeds, was 5.4 puppies.

For those interested in average litter size by breed: The largest average litter size was in the Rhodesian Ridgeback with an average of 8.9 pups per litter. The Toy Poodle and Pomeranian had the smallest average litter size – 2.4 pups per litter. And the Border Terrier (because I’m biased) had an average litter size of 5.1 pups per litter.

This study found that litter size was influenced by the size of the breed, the method of mating, and the age of the bitch. Litter size was not affected by season of birth, or the number of litters a bitch had had.

Size of the breed

This study examined dogs based on average breed size. They were classed as miniature breeds (<5kgs), small breeds (5-10kgs), medium breeds (10-25kgs), large breeds (25-45kgs), and giant breeds (>45kgs). Bitches were recorded against the average size of a dog for their breed and not specifically on the size of that given bitch.

“When looking at all the … litters…, mean litter size increased with the size of the breed. The mean litter size was 3.5 in miniature breeds, 4.2 in small breeds, 5.7 in medium breeds, 6.9 in large breeds, and 7.1 in giant breeds.”

The feature of larger dog breeds having larger litters is not a new thing – this phenomena is consistent across other studies. But this study is different as it found that it wasn’t just size of the breed that mattered…

Age of the bitch

The first analysis of this data showed no significance with the age of the bitch, however, once breed size was taken into account, there were two trends apparent:

  • In small and miniature dogs, young and old bitches had smaller litters than the ages in between.
  • In larger breeds, increasing age corresponded with decreasing litter size. (Young bitches of larger breeds produced the largest litters – unlike small and miniature breeds.)

Predicted litter size by the age of the bitch for the five different breed size groups from Borge et al. study.These results are a little different to other studies, which have shown smaller litter sizes as bitches get older. (As in, the results this study got for larger breeds was seen in all breeds in previous studies.) It could be that smaller sample sizes in other studies may have missed this, or that other studies used larger breeds as their data set instead of small or miniature breeds. One suggestion is that small breeds may not mature as quickly as previously believed, and so they’re not able to reproduce until they reach that mark. (To me, this kind of makes sense – considering small breeds often live longer, then it’s likely that they mature more slowly, too.)

Method of mating

Like the age of the bitch, the first analysis on the data didn’t show a significance change in litter size based on mating method. However, when the data set was adjusted for breed, breed size, and age, naturally mated bitches had significantly larger litters than those who had been AIed (either fresh or frozen).

A decrease in mean litter size of 0.4 puppies would be expected for litters conceived with AI with fresh semen and 1.3 for AI with frozen semen, both compared to natural mating.

Things that didn’t matter

The number of litters a bitch had previously didn’t influence the size of her litter. (However, older bitches normally had had more litters – and their age did influence litter size.)

The season the litter was born in did not influence litter size.

Conclusion

Size of the breed, age of the bitch, and the method of mating are three factors work together in determining litter size. It’s not one thing – it’s all three.

“… the size of the breed, the age of the bitch and the method of mating were found to influence litter size in purebred dogs when controlling for breed, with the size of the breed as the strongest determinant.”

This study is better than past studies in this area for its huge sample size, its variety of breeds, and the fact that it considers all puppies in a litter (not just those registered, as some past studies have done). In this way this study is unique. It is probably a pretty reliable data pool for purebred dogs, too, as 90% of purebred dogs in Norway are registered with their kennel club.

Things to consider regarding the vigour of the results:

  • It’s a retrospective study.
  • It does not include data from litters where all pups were born dead.
  • Calculating mean litter size is hard, because of % made up of small or large breeds. Small breeds are currently popular, so could perhaps pull down the mean litter size seen in this study. Studies done in different countries, with different breeds being popular, is likely to result in different results.
  • There is a relatively small sample of bitches who were mated not-naturally in this study, so the results should be interpreted cautiously, however the results are consistent with previous findings.
  • This study only groups dogs by weight – not by body shape. This might yield differences. (A neapolitan mastiff is really different to a greyhound.) And they group them by weight average of breed, not the weight of the individual bitch
  • This study looked at only two years and the researchers wonder if there might have been more variation in season of birth if there was more time taken into consideration.

In conclusion: Based on this study, breed size is the strongest determinant for litter size in a dog. The age of the bitch and the method of mating were also significant predictors of litter size. These three things interact, making litter size predictions difficult!

Acknowledgements:

Borge, KS, Tonnessen, R, Nodtvedt, A, & Indrebo, A 2011, “Litter size at birth in purebred dogs – A retrospective study of 224 Breeds”, Theriogenology, 75, 911-919.

Thank-you to Waldwiese Kennels for the cover image – a litter of longhair weimaraner puppies.

03/3/16

Photographic Guide to Saving Swimmer Puppies

Saving a swimmer puppy

 

 

I’m proud that, for a number of years, the most popular post on this blog is ‘How to Save a Swimmer Puppy‘. However, I am frequently asked for photographs to illustrate the techniques I mentioned. I have recently had a litter of puppies, so I could stage images showing techniques on young puppies for saving a swimmer puppy.

 

Sling Method

This is by far the most simple method. I use a pillow case, suspended from the back of a chair, and then the puppy is placed inside the pillow case, meaning the puppy is basically in a hammock. When the puppy is placed in the hammock, is important that their legs are tucked underneath them, or the puppy is on their side.

It’s important that the puppy is not allowed to get cold while in this sling, too. You can warm the material of the hammock before placing the puppy inside, and then you can also put a heat pack underneath, on the ground, too (as hot air rises).

You can do this several times a day, ensuring that the puppy stays warm and gets plenty of time to feed in between its time in the sling. Puppies are surprisingly tolerant of this process and rarely object when their stomach is full and their a good temperature.

This is a (zebra-print) pillow case that is suspended on the back of a red chair. Inside, is a baby puppy.  This process will help to fix swimmer puppies.

This is a (zebra-print) pillow case that is suspended on the back of a red chair. Inside, is a baby puppy.
This process will help to fix swimmer puppies.

A puppy (little black blob at the bottom) in a suspended sling. This will help puppies recover from swimmer syndrome.

A puppy (little black blob at the bottom) in a suspended sling. This will help puppies recover from swimmer syndrome.

 

 

Handcuff Method

Using electrical tape, you can create handcuffs that pull the puppies legs inwards, preventing them flailing out to the side as a swimmer. It’s important when using this method that you don’t do it too tight. (To be honest, when I’ve used this method, I’ve had it fall off numerous times a day because of how loose I make it. Fine by me!) You also want to make sure you don’t put too much length between the cuffs – remember the cuffs are supposed to pull the pup’s legs inwards, so if you make the cuffs too long, then the puppy’s legs are still going to be able to swim.

Tools required for the handcuff method: Electrical tape and a pair of scissors!

Tools required for the handcuff method: Electrical tape and a pair of scissors!

Step one: Cut a length of tape. We only need one length of tape, and the exact length will depend on your puppy and how far east west its legs are.

Step one: Cut a length of tape. We only need one length of tape, and the exact length will depend on your puppy and how far east west its legs are.

Step three a: Make one loop of the handcuffs. (This image is for illustration purposes - in reality you'd need the puppy's leg in that loop!)

Step two a: Make one loop of the handcuffs. (This image is for illustration purposes – in reality you’d need the puppy’s leg in that loop!)

 

 

 

 

 

 

 

 

 

Step three b: Make a second loop of the handcuffs. (Photo for illustration purposes - in reality, there would be a puppy with a leg through each loop!)

Step two b: Make a second loop of the handcuffs. (Photo for illustration purposes – in reality, there would be a puppy with a leg through each loop!)

I’m sorry that I am not much of a photographer, but here are some pictures to try to illustrate how these handcuffs look actually on a puppy.

A puppy in swimmer handcuffs.

A puppy in swimmer handcuffs.

A puppy in swimmer handcuffs.

A puppy in swimmer handcuffs.

A puppy in swimmer handcuffs.

A puppy in swimmer handcuffs.

The benefits of the puppy handcuffs is that they can stay on for long periods of time, and the puppy can still feed and cuddle mum and litter mates while wearing them. Sometimes mothers will remove the handcuffs, and sometimes they fall off, so you are likely to have to put on new handcuffs several times a day. Initially, for a severely affected puppy, you may need to start with long handcuffs then reduce the distance between the handcuffs over time. Puppies are surprisingly tolerant of the handcuffs and rarely fuss once they’re on and they’re back at the milkbar!

 

For more tips please do see How To Save a Swimmer Puppy.

04/6/14

How to find a good dog breeder

Purchasing a Dog or Puppy: What to look for in a breeder

 

So you have made a decision to add a dog or puppy to your family. Congratulations!

But how do you make sure you’re getting a puppy from an ethical source?

It’s not a ‘black or white’ matter. There is no definitive issue that makes a breeder ‘good’ or ‘bad’.

Instead, here’s a guide which talks about necessities, niceties, and red flags.

 

Necessities

If your breeder doesn’t do this then walk away…

  • Breeder shows concern and regard to the health of dogs and puppies – either in health testing or in the studs used (e.g. choosing old studs that show they’re healthy, using DNA testing, using x-rays, and other relvant tests)
     
  • Breeder shows concern and regard to the psychological well being of their dogs and puppies – either in providing enrichment on site, by frequently taking their dogs ‘out and about’, by using Dunbar’s methods of raising puppies (with toilet area, kongs, socialisation), and preferably a combination of these methods.
     
  • The breeder has a clear purpose in their breeding program that goes beyond ‘breeding pet puppies’ – they may enter their dogs in dog shows, participate in agility or obedience with their dogs, or have dogs that compete in working dog trials
     
  • The breeder’s dogs approach you in a friendly and sociable way. You are able to interact with and handle all dogs on the property. The mother should be available and should show exceptionable sociable behaviour.
     
  • The breeder is willing to provide life-long support to you as a puppy buyer – including taking back the dog at any point things ‘don’t work out’
     
  • The breeder happily shows you all the dogs in their care
     

 

Niceties

It’s nice for the breeder to do any of these things, but don’t be concerned if it doesn’t happen.

  • The stud dog is on site
     
  • The breeder asks you lots of questions about your household and what you’re looking for
     
  • There is a sales contract that goes beyond simple money exchange
     
  • The breeder can show registration or affiliation to an organisation with a code of conduct/ethics
     
  • The breeder can recite pedigrees and seems to be oozing with knowledge about the breed
     

 

Red Flags

If any of these items take place, you may want to reconsider purchasing an animal from this breeder.

  • The puppies are not vaccinated
     
  • The breeder seems overly concerned about the purchase price
     
  • Not all adult dogs are sociable and friendly
     
  • Part of the breeder’s sales pitch is ‘lots of colours available’ or ‘will grow up big’ or ‘will stay tiny’ or ‘rare!’
     
  • The breeder asks for deposits before a bitch is mated
     
  • The breeder sells puppies together to the same pet family
     
  • The puppies are crossbreeds which seem to have no real purpose (ask, how do they fit into the clear purpose of their breeding program?)
     
  • The puppies are crossbreeds and are given a fancy name like ‘labradoodle’ or ‘spanador’.
     
  • The breeder does seem to be putting the hard sell on you – they’re saying “if you put a deposit down today, I’ll take $100 off the asking price” or “If you don’t buy him now, I have someone coming at 2 o’clock who will buy him”.
     
  • The breeder breeds more than 3 different breeds of dogs
     

stop sign

 

Do Not Buys!

If a breeder performs any of the following points, then do not purchase a puppy and look elsewhere.

  • You cannot meet the mother or father in any circumstances (e.g. ethical breeders, even if the stud dog owner is interstate that should be able to say ‘you can meet them if you really want to go interstate’)
     
  • Puppies are not microchipped – in most states of Australia, this is a legal requirement
     
  • The dogs or puppies seem unhealthy or in poor condition (dirty, matted, skinny, fat)
     
  • The adult dogs are not sociable and friendly, especially if many of the adult dogs are not friendly
     
  • The breeder is unwilling to show you all the dogs at their home
     

 

Is there anything you would add to this list?

 

Further reading:

Red Flags: Warning signs when dealing with a breeder

How to tell if your dog breeder is responsible

A puppy ‘with papers’ from a ‘registered breeder’

Select, select, select

Dog Breeders: Don’t produce lemon puppies

01/10/14

CECS in Border Terriers

ResearchBlogging.org Regulars of this blog will know that I breed border terriers, and I am excited to share with you some new and ground breaking research within the breed.

In December, the Journal of Small Animal Practice published an article on canine epileptoid cramping syndrome (or CECS) in border terriers. This is exciting because it is the first academic article to consider this condition in border terriers, and it therefore documents and legitimises the condition.

 

This is Chip (Au & NZ Ch Dalshoj Chippendale ME TD). He does not have CECS but he is a border terrier.

This is Chip (Au & NZ Ch Dalshoj Chippendale ME TD). He does not have CECS but he is a border terrier.

Research Design

  • A small study of 29 border terriers.
  • There were 33 respondents in all, but 4 dogs were excluded for not meeting the criteria.
  • Recruitment took place through veterinarians, using dogs that had diagnosed and treated for CECS.
  • In 14 of the cases, owners were questioned about their dog’s episodes. In 15 cases, videographic evidence was used.
  • In order to be included in the study, dogs had to:
    • Have a one year history of episodes (i.e. abnormal involuntary hyperkinetic movement)
    • These episodes did not include epilepsy-like symptoms (like loss of bladder or bowel control, hyper salivation, or loss of consciousness)
    • Have other medical ruled out (if possible)

 

What happens before a CECS episode?

  • 18 out of the 29 owners felt they could predict the onset of an episode.
  • 11 out of the 29 dogs became ‘quieter’ before an episode.
  • 6 out of the 29 dogs sought comfort in their owners before an episode.
  • 4 out of the 29 dogs would vomit bile or eat grass before an episode.
  • While most episodes were unpredictable, some owners felt that excitement, waking from sleep, and stress were all triggers.

 

So what does a CECS episode look like?

  • Generally, an episode lasts from 2-30 minutes.
  • All owners felt their dog was uncomfortable during the episode.
  • Most dogs had difficulty walking (27 of the 29 participants).
  • Most of the time all four limbs are affected (25 of the 29 participants).
  • Most dogs had at least some time that they were unable to stand (22 of the 29 participants).
  • Most had a mild tremor (21 of the 29 participants).
  • Most had the head or neck affected (21 of 29 participants).
  • Most had dystonia (muscle tremors) (22 of the 29 participants).
  • Many had the back and abdomon affected (16 of the 29 participants).
  • Some licked the air (14 of 29 participants).
  • Some excessively stretched (14 of 29 participants).
  • Some had all four limbs go rigid (14 of 29 pariticpants).
  • Some had the tail affected (11 of 29 participants).
  • Some dogs got a rumbly tummy (11 of the 29 participants).

 

What happens after an episode?

  • Most owners (18 of the 29) described their dogs as acting similar after an episode as before.
  • 11 of 29 respondents were quieter after an episode.
  • 4 of the 29 participants sought human company after an episode.
  • 2 of the 29 participants were hungry after an episode.

 

What helps reduce symptoms?

  • Most owners found the condition could be managed by diet. 19 of the respodents changed their dog’s diet as a result of their condition, and over 50% thought that this helped.
  • Drugs did not help the condition (including phenobarbital, potassium bromide, and buscopan).
  • Once an episode had started, none of the owners in this study thought they could change the course of the episode.

 

What is CECS correlated with?

  • In short: Not much!
  • Dogs appeared normal despite: blood tests, magnetic resonance imaging, cerbospinal fluid collection and analysis, and neurological examinations.
  • “No significant underlying metabolic, cardiovascular, respiratory, orthopaedic or other neurological conditions were identified in any respondent.”
  • 15 of the 29 borders also had skin disease.
  • There is “an apparent association” between CECS and digestive or food intolerance issues.
  • CECS is not epilepsy. Dogs who have CECS differs from epilepsy as affected dogs remain conscious during an episode, have longer episodes, and do not respond to medication.

 

Implications for Breeders

  • Most dogs had their first episode before 3 years. This may mean that only breeding borders 3 years and older, who are asymptomatic, is a way forward. (But some dogs started cramping at 0.2 years, and some at 7 years, so there’s no guarantees.)
  • 10 of the 29 owners (34%) felt that CECS had a negative impact on the dog’s quality of life. While this is a significant number, it is reassuring to think that most owners (66%) therefore did not think that CECS negatively impacted on their dogs life. This is not a way to justify breeding CECS affected dogs, but it is reassuring to know that the condition does not seem to be incredibly debilitating in many situations.
  • Skin disease is correlated with CECS. Any dogs affected by skin disease should not be considered for a breeding program.
  • For those trying to determine the inheritance of CECS, it is important to note that CECS is not epilepsy. A condition that can be controlled by medication is almost certainly not CECS, and it would be hazardous to lump the two conditions together.

 

Congratulations and thank-you to those border terrier people who have been campaigning and working behind the scenes for research like this for many years.

I hope this is the first of much research to come.

This is Clover (Ch Burrowa Blue Flame ME TD DWDF.S) and Chip (Au & NZ Ch Dalshoj Chippendale ME TD). Neither of them are CECS affected, but they're pretty cute.

This is Clover (Ch Burrowa Blue Flame ME TD DWDF.S) and Chip (Au & NZ Ch Dalshoj Chippendale ME TD). Neither of them are CECS affected, but they’re pretty cute.

 

Reference:

Black V, Garosi L, Lowrie M, Harvey RJ, & Gale J (2013). Phenotypic characterisation of canine epileptoid cramping syndrome in the Border terrier. The Journal of small animal practice PMID: 24372194

11/19/13

Dog Aggression in a Breeding Program

Should you breed from a dog that is dog-aggressive?

"Deez" was surrendered into rescue having almost-exclusively lived in a backyard for 2 years. Despite this, he was friendly with other dogs. While his breeder wasn't what would be regarded as highly ethical, they obviously were producing dogs with good temperaments.

“Deez” was surrendered into rescue having almost-exclusively lived in a backyard for 2 years, with minimal interaction with other dogs. Despite this lack of socialisation, he was friendly with other dogs. While his breeder wasn’t what would be regarded as highly ethical, they obviously were producing dogs with good temperaments. His sociability with other dogs was the reason we were able to so easily place him into a new home – he now has another dog for company.

There’s four questions concerning that particular dog’s aggression that I would consider when elevating a dog’s suitability for a breeding program.

Firstly, if the dog is biting/attacking other dogs, is it illustrating bite inhibition by not actually doing damage to other dogs? If a dog is ‘attacking’ at a lot of dogs, but never doing damage, then this is a good sign that the dog is not intending to physically harm other dogs.

Then, how common is this type of aggression in this breed? Very common, uncommon, rare? In some breeds, all you can do is pick ‘the best of a bad bunch’. Complimentary temperaments in proposed matings are important, too (you wouldn’t put a ‘bad dog’ to another ‘bad dog’, for conformation or temperament).

Is the dog so aggressive to other dogs that you can’t achieve a natural mating? If the dog is not psychologically sound enough to have sex then it shouldn’t be bred from. Consider that many solitary species, like tigers, bears, rhinos, are generally territorial and aggressive to one another – yet, they still able to reproduce naturally. That is, the instincts associated with reproduction are strong enough to override a natural dislike to their own kind. Dogs, who are naturally social animals, should at the very least have a temperament conductive to natural matings.

Finally, a question to ask yourself as a breeder: Would you be satisfied if your puppy buyers ended up with a dog of similar temperament?  That is, would you be proud to produce a dog with similar dog-aggression? Are you puppy buyers able to manage or train against dog-aggression? Dog owners want dogs to be ‘friendly’, and producing dogs with dog-aggression are likely to fall short of the owners’ expectations.

 

What do you think? Should a dog that has dog aggression be bred from? Under what circumstances?