The Rumen Room Podcasts

40. The role for dietary iodine in dairy cows before and during mating

This episode takes a deep dive into the topic of dietary iodine requirements of cows - and the relationship (or not) of iodine intake with the reproductive performance of cows.
Iodine is well down the priority list when tackling challenges of poor reproductive performance. Body condition score at calving and the extent and duration of body condition loss (‘negative energy balance’) are by far the more important factors that drive successful reproductive outcomes in dairy cows.
That said, iodine features every season in conversations on farm about improving mating outcomes. “Iodine improves expression of heat by cows” has been around for a long time as a topic of conversation. Fact or fiction? Join us in this latest podcast to explore the potential relationship between dietary intake of iodine by cows (and some discussion of ewes too) and the wellbeing of ruminants.  
As always, the content of this podcast is of a general nature only and is never intended to replace the advice of your very own local veterinarian and qualified dairy nutritionist.
Where to find different parts of this podcast:
1.20 Overview of the topic of iodine and the reproductive performance of pasture-fed dairy cows
1.55 Iodine might play a possible role in cow fertility but more than 100 other factors determine if cows will mate successfully – particularly cow body condition score at calving and extent and duration of body condition loss between calving and mating
5.00 Iodine increases expression of signs of oestrus (heat) by cows – fact or fiction?
7.45 Why do cows require iodine in their diet? It’s all about thyroid hormones, needed particularly by the unborn calf.
9.30 What do thyroid hormones do inside the cow (and unborn calf) or indeed inside the ewe (and unborn lamb)
12.00 Goitre in newborn calves and lambs – very rarely seen in adult stock
14.10 Aside from clinical signs in newborn animals born to cows and ewes, there’s not much to see in iodine deficient cows and ewes
16.40 Iodine and the functionality of the reproductive system in cows
17.00 The “HPO” axis that drives reproductive function and the role for iodine
18.45 Possible changes to reproductive function when iodine status is low
22.30 The challenges of diagnosing iodine deficiency in cows (but discuss this topic further with your vet)
25.15 Pasture levels of iodine are very variable!
25.50 Salt spray off the sea – adds small amounts of iodine to pasture
26.30 Other factors that influence iodine intake by pasture-fed cows
27.05 Goitrogens in forage feeds – reduced conversion of iodine to thyroid hormones 
29.05 Types of goitrogens in NZ forages
31.50 Iodised teat sprays and iodine status of lactating dairy cows
33.25 Taking the simple approach, not testing for iodine, can we just add iodine to the diet?
33.55 Care with supplementing with iodine, some countries, upper limits to iodine supplementation!
34.20 Selenium deficiency contributes to thyroid hormone challenges as well

39. Summer forages for lactating dairy cows. The Mark and Courtney Harris story

With the ever-increasing inconsistencies of summer weather impacting on dryland dairying, forage crops deliver a valuable bulk of high-quality summer and early autumn feed. In our latest dairying-themed podcast, host Charlotte Westwood is joined by Waikato dairy farming couple, Mark and Courtney Harris - to learn of their investigations into the fit of different summer forage crops for their dairy business.
Farming across two properties in the northern and southern reaches of the Waikato, summer crops form an important feature of Mark and Courtneys dairy systems. Chicory and summer brassicas are cost effective feeds for their herds, helping to to offset the absence of sufficient quantities of high quality pasture that would otherwise compromise summer milksolids production.
Mark and Courtney discuss how four years of on-farm work that has compared cow responses to either chicory or summer brassicas has taught them much about the fit of summer crops within their dairy business.
Which is better as a summer forage crop for cows? Chicory or brassicas? Which crop type should we plant? Tune in, Mark and Courtneys findings might surprise you.

38. Feed for your stock - Spring planting decisions; “What’s In the Bag” – with agronomist Brian Young

With spring planting coming up fast for us here in New Zealand, our latest episode focuses on decisions around choosing the right pasture and forage crop seeds.
Host Charlotte Westwood chats with guest podcaster, Southland agronomist Brian Young about all things seeds. Brian’s background includes farming (sheep and beef, and dairy), shearing, working as a rural retail rep and, for the last 9 years, working with PGG Wrightson Seeds, advising farmers how to grow the very best pastures and forage crops.
What’s involved in choosing the right type of seed? Just what is in that bag of seed?? How do we know that the seed will be right for us, will grow lots of feed for our stock, and won’t bring in unwanted weeds? Brian steps us through the information we need to make informed choices when choosing the right seed for us.  
There’s a bit of info for everyone in our latest podcast.

37. Setting ewes up well through lambing – Pasture-based tips and tricks

This episode carries on from Episode 36, expanding the topic around feeding ewes well through lambing. First up, we cover off on the challenges of stress, and of pre-existing animal health conditions on the ability of a heavily inlamb ewe to look after herself and her unborn lambs well, from a nutritional point of view. The importance of getting stocking rate right at the point of set stocking is discussed, and we investigate ways to calculate what your stocking rate should look like. Lower than ideal pasture covers at the time of set stocking - such a challenge! Short and longer terms ideas of improving pasture-feeding levels at lambing are discussed.
Content of our latest podcast:
1.50: Feeding ewes well; more kg of lambs weaned per ewe mated
3.00: Non-nutritional factors that impact on the nutritional status of ewes in late pregnancy
4.20: The role of stress in late pregnancy; Weather, yarding, disrupting lambing ewes, pre-lambing shearing too close to lambing
7.30: Internal parasites and nutritional status of ewes
10.20: Illness and injury – risk of ewe undernutrition
12.15: Ewe body condition score (BCS) and ewe nutritional wellbeing through lambing
17.35: Working to improve ewe BCS at lambing – a longer term view
19.45: Pregnancy scanning – An incredibly valuable tool in managing ewe nutrition
22.00: Setting the stocking rate for twin/triplet-bearing ewes at set stocking, prelamb
25.50: Beef and Lamb FeedSmart – just one of many tools available to define ewe nutrition through lambing
33.10: Feeding ewes well vs. risk of bearings
36.00: Managing pasture deficits at set stocking; (a) Short term strategies
39.10:  Managing pasture deficits at set stocking; (b) Longer term strategies

36. Pregnancy Toxaemia (“Sleepy Sickness”) in pregnant ewes

Our latest sheep-themed podcast covers a topic that can challenge our pregnant ewes when they have a belly-full of lambs in late pregnancy. Pregnancy toxaemia is a metabolic disease of ewes caused by underfeeding and/or stress when ewes, often those carrying twins or triplets, reach the final stages of late pregnancy. The podcast covers off what pregnancy toxaemia is (and how and why it occurs), clinical signs you might see in affected ewes, then finishes up with an overview of approaches to treating ewes with pregnancy toxaemia.
*NOTE: This podcast contains information about pregnancy toxaemia in ewes, however podcast content is NOT intended to substitute advice and recommendations from your own veterinarian about the health and wellbeing of your ewes*
Content of our latest podcast:
1.30: An introduction to the current episode
3.50: What is pregnancy toxaemia in ewes?
7.50: Do we know the incidence of pregnancy toxaemia in New Zealand ewes?
9.50: The two ‘syndromes’ of pregnancy toxaemia in New Zealand ewes
12.10: Why is pregnancy toxaemia more likely to occur in twin and triplet bearing ewes?
14.10: What signs should we look out for if we suspect pregnancy toxaemia in ewes?
21.10: Impacts of pregnancy toxaemia on as yet unborn lambs, and ewe colostrum and milk production
22.00: How pregnancy toxaemia impacts a ewes immune response (ability to ‘fight off’ infections and internal parasites)
24.25: Basic approaches to treating ewes with pregnancy toxaemia (these suggestions are NOT intended to replace the advice and recommendations from your own veterinarian)
 

35. Rumen bloat (“frost bloat”) in cattle that eat frosted, frozen winter pastures and forage crops

During mid-winter, it’s not uncommon to start the morning with frosted forages (pastures, winter brassicas, fodder beet and green feed cereals).  For break / strip grazed animals that are hungrily waiting for their regular shift onto a new break, frosted forages can potentially increase risk of rumen bloat or "frost bloat". 
In this our latest “bite-sized” Rumen Room Podcast, we cover why grazing ruminants, cattle particularly, are at greater risk of rumen bloat when they eat frozen pastures and winter forage crops.
Preventative strategies that reduce risk of “frost bloat” in animals that graze frozen, frosted forages are discussed. 

34. Reducing risk of low blood calcium at calving - Dairy cow springer (pre-calving) diets

In this our latest podcast, we focus exclusively on the diet of “springer” dairy cows (otherwise known as “close up dry cows”).
Many factors are important when designing springer cows diets – relating not only to calcium metabolism but also to do with dietary energy, protein, fibre and, of course, the requirements for other minerals and vitamins.
Focusing specifically on how a springer cow diet influences calcium metabolism through calving and during early lactation, we’ll cover a range of different topics. First up, the basics of calcium metabolism are discussed then moving onto the reasons why recently calved cows end up vulnerable to low blood calcium (hypocalcaemia), particularly when freshly calved cows are milked for the first time.
Strategies to lessen the extent and duration of hypocalcaemia in freshly calved cows inevitably start with the design of a springer cow diet. A range of springer pre-calving diet-based strategies exist, including but not limited to focusing on appropriate dietary magnesium management, dietary DCAD (dietary cationic anionic difference), supplementation with very low or very high rates of calcium, use of calcium/phosphorus binders, avoiding high dietary phosphorus before calving, and vitamin D supplementation for springers.
We don’t cover anything about fresh cow (colostrum) and early lactation management in this podcast, all content focuses wholly on the springer cow. Watch this space for future podcasts covering further aspects of management of the periparturient cow.
**Disclaimer – this podcast is NOT intended to replace the advice from your own veterinarian and qualified dairy nutritionist specific to your farm, your feeds and your cows. Please consult directly with your vet and nutritionist about challenges of low blood calcium / milk fever / downer cows in your herd**

33. Intramuscular fat (IMF) deposition in finishing animals – animal-related factors, and dietary nutrition

Intramuscular fat (IMF) is fat that’s deposited between and within individual muscle fibres (cells) in the skeletal muscle of animals. Also referred to as ‘marbling’, consumers of red meat often prefer meat that contains a higher level of IMF due to an enhanced eating experience.
In this, our second in a two-part series focusing on IMF in ruminant animals, we carry on a discussion around IMF from part one (Episode 32) that covered the basics of IMF in red meat.
In Episode 33, our current episode, we further explore the subject of IMF, covering first up, some of the animal-based factors that influence extent of IMF deposition. In the second part of this podcast we discuss the importance of the dietary nutrition of finishing animals to achieve desired levels of IMF in red meat.
The following topics are covered within Episode 33, at times within the podcast,  listed below at 
2.41: An introduction to the current episode
3.45: The importance of animal genetics as a key driver of IMF deposition in finishing animals
6.33: Animal-specific factors, other than genetics, that influence IMF
11.08: The conflict of outcomes between (a) keeping fattening animals on farm for longer, to achieve higher IMF %, when (b) mature, fattening animals are extremely inefficient converters of feed to liveweight gain
12.22: The differences in feed conversion efficiency (kg of dry matter per kg of liveweight gain) for young growing animals, compared to that of older fattening animals
16.47: The effects of the sex of an animal on efficiencies of IMF deposition
20.44: Effects of dietary nutrition on IMF deposition
21.00: Maternal nutrition and subsequent potential IMF deposition by progeny
26.08: IMF deposition during the finishing phase – the influence of dietary nutrition
26.56: Blood glucose drives IMF deposition – the ‘101’ basics of biochemistry helps define why blood glucose is important - including the “cricket wicket” of fat structure
29.51: IMF fat cells – glucose is the IMF cells ‘fat manufacturing ingredient of choice’
34.40: Maintaining high blood glucose levels on temperate pasture & forage crop systems
37.00: Developing a farm plan for more IMF within temperate forage systems
40.10: High dry matter intakes and IMF deposition
41.55: Very high quality forages and the potential role for rumen pH and IMF
43.29: Lamb finishing on chicory and chicory/temperate clover blends – IMF and Omega 3 polyunsaturated fatty acids
44.33: Trying to understand the “black box” of how chicory/clovers support more IMF and/or more Omega 3 fatty acids
47.23: Length of time on finishing feeds for ideal IMF deposition
48.43: Micronutrients and IMF deposition
 

32. An introduction to intramuscular fat (IMF) deposition in finishing animals

Intramuscular fat (IMF) is fat that’s deposited between and within individual muscle fibres (cells) in the body of animals. Often also referred to as ‘marbling’, the consumers of red meat often have a preference for higher IMF meat due to an enhanced eating experience.
In this, our first in a two-part series that focuses on IMF, we lay the foundations for our discussion around IMF. We define what IMF is, and describe why the increasingly discerning consumers prefer meat that contains a higher percentage of IMF. We further scene set around fat metabolism with a discussion around the four key fat depots found in a finishing animal and what roles these fat depots play in the day to day existence of our sheep and cattle.
In Episode 33, we’ll build further on this IMF topic by looking at a deeper level of detail around animal and nutrition-based factors (at a farm level) that influence the extent of IMF deposition in finishing cattle and sheep.
Have a search within this current Episode 32 for topics of interest relating to an introduction to IMF.
0:55 Introduction to Episode 32
2:52 Outlining the content of the episode
4:12 Intramuscular fat (IMF) defined and is ‘marbling’ the same thing?
7:30 Why do consumers of red meat specifically request high IMF meat and why does IMF improve the eating experience for consumers?
14:10 Fat depots around the body, it’s not all about IMF!
14:40 Fat as an essential energy reserve for animals – both white a brown fat (Brown Adipose Tissue; BAT)
17:18 The role of fat to protect internal vital organs inside the animal
18:18 The role of fat to protect the musculoskeletal system
18:44 Intermuscular fat is not the same as intramuscular fat
19:15 Fat as an endocrine organ (that produces hormones, who would have thought!)
21:02 IMF is the last of the four fat depots to be laid down as an animal ages/matures
25:08 IMF is the first of the four fat depots to be mobilised when animals are underfed, eat poor quality feed and/or are stressed
 

31. The dry off process for lactating dairy cows. Part Two

This is our second of a two part series all about “drying off” lactating dairy cows. Part One of this two-part series (Episode 30) covered off the basics of why the cow and her udder need a dry period to rest and recuperate in preparation for a new lactation. What a “good” dry off process might look like was discussed, as well as the impact of once-a-day milking before dry off for cows that are still producing a lot of milk in late lactation.
In this, Part Two of the two-part series about drying off dairy cows, we explore the role for nutrition before, through and after the dry off process. We’ll cover different ways to reduce the intake of energy and other nutrients for cows during dry off, with the aim to make the process as successful as we can - for both the cow but also for you and your business.
Below hopefully will help you find the content if you’ve not got time to listen in to the whole podcast. Enjoy! 
3.00 Introduction and overview of this podcast
4.50 Combining nutritional  manipulation and milking frequency for high producing cows at dry off
5.35 Nutritional strategies to help dry cows off – things to consider
7.35 Making decisions around drying off – how much milk are your cows producing?
10.20 Nutritional concepts to help drop milk production before dry off
13.10 Concentrate (grains, meals) feeding before dry off
16.00 Total amount of feed on offer and/or reducing nutrient density of feeds through dry off
21.35 Unintended consequences during dry off; condition loss and immunosuppression
29.50 Importance of adequate trace mineral status through dry off
31.15 Reducing dietary protein intake as a potential option to help with dry off
42.40 Planning ahead for nutritional approaches to dry off – starting the year before
49.20 Conserved feeds for dry off
54.30 Specific points around use of high rates of maize silage for drying off
56.10 Provision of ample, top quality tasty drinking water for cows through dry off – an essential part of the dry off process