Feeding for Breeding

[Scotts1au]

Hi all

I'm interested in feeding strategies used by people in the lead up to breeding. This includes what and why and whether there are any key indicators that you use to know that you are on track in your preparations.

I'm also interested in feeding strategies used while the females are gravid.

To kick off.

To cut a long story short, from many years of breeding lowland blotched to more recently breeding Alpines the simple strategy of feeding the heck out of them at the end of summer seems to pay off. Not only that moving from a more mixed diet to one almost completely of dog food. Prior to brumation each of my females was approx. 800g and ave. of about 55cm (22inches), this is an ave. of 14.5g/cm of length. At least for this line of Alpines this figure might be a good indicator.

My belief is that at least for blotched blueys - their wild diet is predominantly animal product - grubs, bugs, worms, fungi - which means saturated fat and high protein. Indeed both are essential components of sex hormone production, particularly if the predominant source of energy is the breakdown of long chain saturated fats in Spring.

It is common knowledge in blotchies that the condition of females prior to adequate brumation is a major factor in reproductive success, along with synchronising males and females by exposing them to the same conditions.

I was interested in discussion on another related forum about the use of dog food on Shinglebacks for breeding, I believe the issues and requirements are similar for them and blotchies despite their natural higher reliance on vegetable matter for food in the wild.

I'd be interested in reading anyone elses thoughts on this.

[Jeff]

In general, I have not changed the diet of my skinks prior to breeding. I do feed them large quantities to insure that they get as much as they want leading up to brumation. I make sure to give them more than they can eat in 24 hours.

The higher protein theory is interesting. This year I did switch the protein part of my rugosa diet from mostly cooked chicken to mostly beef dog food. I don't know for sure if that has had anything to do with it, but last year I didn't get any breeding activity from them, and this year, lets just say it's been like a toga party in there.

[critterguy]

shinglebacks do come from an extreme environment so perhaps more protein could be a sign of a good time to breed. In years when they depend mainly on vegetation perhaps breeding is supressed.

It'd be interesting to know the fat percentage of wild bluetongue skink diets. Dog food which has been fed has pretty high fat content(usually around 10-15%) compared to foods made specially for reptiles(usually 5% or less from what I've seen). However, skinks seem to do just fine on dog food. Perhaps a diet high in beetle grubs could provide a lot of fat?

[Scotts1au]

I generally don't feed dog food over 6% fat - mine also get a lot of cut up fruits like apple (waste not want not eh). The higher quality ones tend to be leaner, also low fat df varieties are useful.

The fems actually look quite tubby during their pregnancy - but deflate like baloons. My feeling is that being a little overweight during this period is critical to their ability to recover quickly during a stressful period. They can do their initial recovery without chewing into their fat reserves prior to brumation.

Of course the precursors for oestrogen and progesterone production are you guessed good old cholesterol - yep from saturated fats.

[Scotts1au]

See quote below from http://eprints.utas.edu.au/667/2/whole_thesis.pdf

I think anyone serious about reproducing T.nigrolutea let alone other species should read it.

Evidence that reproduction in female in T. nigrolutea might be limited by resource availability comes from the observation that females of this species are believed to also display a multiennial pattern of reproduction throughout the rest of their southeastern Australian mainland distribution (Shea, 1992). Consideration of the possibility of a plastic reproductive cycle that varies in response to environmental conditions was beyond the scope of this project, but warrants further investigation. Additionally, although not quantified here, there may exist a threshold body condition in this species, below which reproduction does not occur. A large reproductive investment in one year may breach this threshold in T. nigrolutea. Such a body condition index (BCI) has been described in the viviparous snakes Vipera aspis (Bonnet and Naulleau, 1994; Bonnet et al., 1994) and Thamnophis sirtalis parietalis (Whittier and Crews, 1990).[i]Evidence that reproduction in female in T. nigrolutea might be limited by resource availability comes from the observation that females of this species are believed to also display a multiennial pattern of reproduction throughout the rest of their southeastern Australian mainland distribution (Shea, 1992). Consideration of the possibility of a plastic reproductive cycle that varies in response to environmental conditions was beyond the scope of this project, but warrants further investigation. Additionally, although not quantified here, there may exist a threshold body condition in this species, below which reproduction does not occur. A large reproductive investment in one year may breach this threshold in T. nigrolutea. Such a body condition index (BCI) has been described in the viviparous snakes Vipera aspis (Bonnet and Naulleau, 1994; Bonnet et al., 1994) and Thamnophis sirtalis parietalis (Whittier and Crews, 1990)

[critterguy]

Interesting stuff-and indeed what I would have figured. Its remarkable blotchies can survive a relatively inhospitable environment for a large ectotherm. Assuming you guys also have Australian water dragons in your region too?(or at least same latitude along the coast). Any monitors?

Good that you mentioned the fat content of the dog food that you feed. That is pretty hard to find-only foods I've found with that kind of nutritional profile are dogfoods made specifically for weight loss. I would suspect other breeders aren't so picky-but I'd love to see more input. Indeed-feeding lots of fruit/veggies decreases the overall fat content of the diet. But as you mentioned fat is important for the production of certain hormones key to reproduction.

[Jeff]

The dog food I feed the majority of the time is 7.0% fat. Some of the things that Scott has pointed out in the past have convinced me to switch dog food occasionally, but I still use one type most of the time. The main reason I use this kind is because it has been used by some breeders with great success for many years. They don't claim that they know exactly WHY it works the best for them, they just know that they have tried many different things, and this particular brand has resulted in robust and healthy skinks. It happens to be a fairly inexpensive brand, but that is 100% irrelevant to me. I use to use a brand that cost 4 times as much, and I would be happy to continue spending that much if I thought that it was best for my skinks.

I have always tended to trust people with years of experience over theories about what SHOULD work best. It seems to me that the more that is learned about BTS, the more the theories and science seem to fall in line with what the long-term keepers have already figured out. I think that both avenues usually lead to the same conclusions if given enough time.

[Alioop]

Critterguy- I just went and checked all my canned dog foods because I was pretty sure I had been tending towards the leaner ones last time I bought them. I don't have any above 5% fat (although I believe the wording is min 5% fat)- Blue Buffalo, Nature's Recipe, Avoderm & Authority. However, all of the Proplan (I have different "flavors") are at 2.5%min fat. And its one of the cheaper foods.

[critterguy]

Made the mistake of not realizing that dry vs wet food the nutritional analysis is quite different. It is better to look at the ratio of protein to fat. It seems to be about 2:1 for most foods(+ or - a bit...significantly less for some foods designed for weight loss).

If i.e if a wet food has about 9% protein-it will probably contain about 5% fat. A dry dog food containing 30% protein will contain about 15% fat. To contrast this Zoomed canned monitor and tegu food(which proudly advertises containing real chicken... and soybeans) which is formulated with 9% protein and .5% fat. Flukers Bearded Dragon food(dry food) has some 35% protein but only 9% min fat. So foods designed for reptiles tend to have much lower fat content than dog food.

Jeff: Mind sharing what brand you've been using?

[Scotts1au]

Dry dog food has fat added back in to make it more palatable to dogs. Don't confuse this with a nutritional need though, this is simply to get them to eat it.

[Jeff]

This is slightly off-topic, but several people have asked me what brand dog food I was referring to above, so I will explain here.



It is Pedigree loaf style with chopped beef. I have heard complaints before from people complaining that this is not "high quality" dog food. My response to that is generally, "How exactly do you define high quality"? If high quality = the most expensive, then you're right, this isn't the highest quality food you can buy. If however, high quality dog food means what produces the healthiest BTS, then I am not aware of ANYTHING out there that has been shown to out perform this stuff. There may be other brands that work just as well, and if you want to experiment for 10-15 years with other brands, then by all means do so, but I have chosen to listen to the people who have already tested many foods for over 20 years.

I think some of the confusion comes from the fact that most less expensive dog food contains more fillers and by-products than many of the expensive brands do. The assumption is made that these things must be bad. My belief is that these things may actually be the reason why cheaper dog foods may, in some cases be better for BTS than the expensive ones. Meat by-products are actually the things that are missing from most of the protein sources that we feed our skinks. The bones, organs and other "gross" things are carefully removed from some dog food. Those are things that I would like included in my skink's diet.

This stuff is just my opinion, and I can not prove any of it scientifically. It has been proven in practice for decades by long-term keepers though.

[critterguy]

Scott: A search through the nutritional analysis of various dry and canned foods does not seem to support the statement that dry has any more fat then canned.

Jeff,

I did a search for that particular food and failed to find it. Perhaps it is discontinued? I'm going to assume Pedigree dog foods are all pretty similar. Are you familiar with which other brands were tried and produced so/so results?

Here is a nutrition analysis for something similar
http://www.dogfoodanalysis.com/dog_food ... 75&cat=all

And a written review of a dry food of the same brand
http://www.dogfoodanalysis.com/dog_food ... =3&cat=all

Not sure what other brands have been tried-but I can't see anything that sticks out about this brand compared to others. Generally speaking high quality dog food contains more meat and less corn/grain/wheat/fillers. Higher quality dog foods typically use potatoes or other nongrain sources of carbohydrates. Pedigree dog food contains lots of corn and wheat, and overall less meat(which is supplied in the form of byproduct meal). However, most low quality dog food will use various meat byproducts in them so this isn't too special. Again, the protein-fat ratio is about 2:1.

I think this seems to mean that BTS are not particularly picky. It also implies it is probably not worth spending lots of money on dog foods since lower quality brands work just as well.

[Scotts1au]

There was a rather long discussion about the relative merits of various types of foods produced for dogs. Interestingly dried food is often a combination of various meal products (bone, fish waste and proteins etc) moooshed up filled and dried with carbohydrate sources and having fats added back at the end of the process - the fats are not those contained naturally in the animal products but rather those added back to the mix to attract the dogs to eat it. For what it is worth there should be nothing wrong with using it in combination with other food sources.

Anyway there is information around ie. other bluey related website that contains articles, one in particular is interesting looking at gut content studies that found something like 80% of the diet of blotchies was invertebrates - typically grubs and other litter critters.

It is interesting to read articles like this one, http://www.animalpetsandfriends.com/Art ... eins/41546 . If one extrapolates then 80% inverts would equate to about 15-20% at least protein content and even higher saturated fat content. I have no reason to think that requirements for other scincoides would be much different. Although because they do eat during the brumation period their weight management requirements would be different.

[critterguy]

Scott: It seems to me that the fat is added back in as a nutritional necessity as well as to increase palatability. Wet foods still come out with about the same protein:fat ratio.

Unless we know what family groups and life stages of insects wild blueys are eating it is hard to have an idea of the fat content of their diet.(the other 20% of the blotchies diet I'd assume is plant matter-I don't think they eat many vertebrates in the wild).

These charts look quite shady, but until I can find better ones here are some nutritional profiles for common insects to compare.
http://chamownersweb.net/insects/nutritional_values.htm

If bluetongues come across mainly larvae(say-beetle grubs and caterpillars) then these will have a quite high fat content. If bluetongues are eating mainly adult insects then fat content is probably less. I doubt bluetongues are very selective other than the fact that they can't catch fast moving insects. I'd imagine their diet varies widely over the course of the year.

[Scotts1au]

They are predominantly larval stages.

To get this convo back on track, I've clearly experienced that the following strategy appears to work well.

Post partum, females should be fed basically as much (dog food or other food source with a balance of protein and saturated fats) whatever your preference as they will eat until you are satisfied with their weight and fat storage which can be seen as general puffing of jowels, upper tail storage. If anything to get them a little overweight, relative to where you would probably like them to be most of the time. The idea being that they don't start the next season in a stressed condition.

In post partum feeding I also sneak some Ca supplement to my outdoor blueys and often replenish their food twice per day.

[Jeff]

Scott, have you found that the blotched breeders you know are able to produce bubs from a female in consecutive years by offering her optimal conditions to put on weight between giving birth and brumation? Also, I am still not clear if it is known for sure that wild blotched normally produce bi-annually. It makes sense that few would be able to put on the necessary condition during the very short time between birth and brumation.

[Scotts1au]

Jeff definately a topic of conversation on Aus websites and appears to be a pretty consistent phenomenon at least in Tasmania and Southern Victoria. There is a good paper here - utas again http://eprints.utas.edu.au/624/1/multie ... _paper.pdf

My previous experience was in Melb that only about 30% of the females would be gravid in any year. I gradually improved this to about 60% by improving feeding care, particularly post partum.

One of Alpines "Pat" had babies again this year. My failure last year had more to do with my males than the females. Norman had been brumated in Southern Victoria and was out of sinc with the females. He eventually mated with a female who had only been placed outdoors to brumate in September (only 1 or so month brumation) who subsequently had 3 babies.

By the time the male was ready, the other females were already past their mating window.

[critterguy]

Wild scincoides seem to give birth pretty much every year(based on a paper I read that found the majority of females observed were gravid). I suppose being from warmer climes they are able to put enough weight back on most years-abundant insect larvae likely are important in this regard.


Scott: Is their any evidence of breeding year in year out wearing down breeders? I recall Ray had one female who produced babies for 17 years in a row!(so I suppose no)

[Richard.C]

dry dog food is generally higher based in fat than wet food,i mostly feed mine on good quality wet food,pal or chum,mostly the pedigree pal,scott you have hit the nail oon the head,the key to getting females to cycle is making sure they have adequate fat reserves before brumation,breeding females are on a 12 month cycle,the more weight they carry the better,especially for consecutive litters,if they lose alot of condition after giving birth,it is to hard for them to regain enough condition for the following season

i have 2 lowlands that had late litters a couple of seasons ago,so late in fact that the other animals had finished eating for the season as temps had dropped,i had to bring them indoors,and they had poor condition the following season,1 is still only just getting back to normal now,the other is actually due for bubs anytime now

theres a lot more to blueys than just cooling them right ,its a 12 month cycle,starting with fattening them up prior to brumation/cooling,feeding when they come out,introductions with males ect,feeding to help females nourish developing young,and more importantly nourish them selves,as developing bubs can sap a female of alot of nutrients,plus you dont want the female to be to skinny after having bubs,so she can regain enough condition before going into brumation again

males also need to be looked after in a similar manner,not so much with weight gain,but they go through periods of not as much interest in food,plus they need the strenght to subdue females

[Richard.C]

ive found alpines easier to breed annually outdoors here in southern vic,same with easterns,easterns generally have babies here quite early,jan/feb,so have alot of time to regain condition prior to brumation,my alpines generally drop in march,the big female usually carries enough condition to have babies the following year,mind you not this season,but more my fault as i didnt feed them super heavily late last season

i think ive ony bred lowlands 2 years running once outdoors here,that was a large female that always carried alot of weight,most dont have the time to regain condition outdoors here as they usually dont drop till late march up until mid april

this season will be interesting,as i took photos of the breedings and they were actually very late this season,latest was alpines on the 2nd of december and thats one of my gravid ones

i also have a heavily gravid eastern female thats yet to drop,march is very late for them here,shes indoors now to protect the babies
spring was quite delayed here this season,hence very late matings,will be interesting to note gestation periods,as apposed to a more normal season