Metabolic & Production Diseases In The Dairy Cow (Nutritional demand and production diseases in the dairy cow) AND Postpartum Esumption Of Cycles Flashcards
What occurs in cow during transition period from close-up to post-partum
Sudden increase in nutrients required for milk production
-Energy demands = MJ/ME (Mcal or UFL)
-Protein demands
-calcium demands
Decrease in dry matter intake in last week of pregnancy
Immuno-suppression-> less geared up to fight infection
A 700kg cow to be alive need how many MJ?
What about after calving?
70MG!!
370-380MJ!!
How many MJ should be added to a lactating cow?
28MJ
How many MJ should be fed to cow before pregnancy?
100-120 MJ
How many MJ in cow goes into her milk?
5MJ
Hypocalcaemia / Milk fever
-common when?
-what happens to animal
-due to what on farm?
-Usually in the first week after calving
• Animal recumbent and weak, cold
• Low Ca – give Ca IV
-Poor nutrition / management in the dry period
Retained Foetal Membranes (RFM)
-what time
-predisposes what
Retained if not passed within 6-12h
Predisposes to metritis and endometritis
Acute post-partum metritis
-happens when
-what is it
-consequence of what
-consequence
• 1 – 21 (30) days PP (1-7 d)
• Inflammation of whole uterus
• Often consequence
of RFM
-death
Chronic endometritis
-what is it
-any systemic signs?
Chronic Inflammation of ENDOMETRIUM
•NO systemic signs
Ketosis
• ‘Clinical manifestation’ of NEB
• High keton bodies (BHB)
• Common in high producing cows
• Over conditioned dry cows (fat cow sydrome)
• Inappetence, milk drop, rapid weight loss, depression, fatty liver or nothing…
• Diagnosis: test
Left displaced abomasum (LDA)
Mastitis
-happens when
-what is it
-different types
Happens around parturition
Inflammation of the mammary gland
Clinical vs subclinical mastitis
Acute vs chronic
Contagious vs environmental
Aim of farmer is to calve down how many times a year for maximum efficiency?
Once a year
Describe the process of annual production cycle and how long each step should be
-begins with calving
-6 weeks of utwrine involution
-6 weeks for breeding and conception
-9 months gestation
-at 12 month period calving again
altogether 1 year
During 6 week period of conception, what is resumed in the uterus of cow?
Dominant follicle growth
LH pulsalitility
Oestrous cycles
—> successful insemination
What occurs during uterine involution?
- Uterine horns return to normal size
- Endometrium restored to normal
- Resumption of ovulation activity and showing signs of oestrous cyclicity
When does first ovulation postpartum occur in each of these species;
-cow
-ewe
Mare
-some
-bitch
-woman
during lactation
after weaning
during lactation
after weaning
after weaning
during lactation
What is the postpartum period of these species
-cow
-ewe
-mare
-sow
-bitch
-woman
25-130 days
> 5 months
7-10 days
30-50 days
> 4 months
> 30 days
What is the common difference in 1st ovulation time between monovulatory species and litter-bearing species?
Mono- 1st ovulation occurs during lactation
Litter- 1st ovulation occurs after weaning
Sequence of hormonal and follicular events leading to ovulation:
- FSH rise for follicle wave emergence
- Dominant follicle selection as normal
- Increase in GnRH pulsatility to replenish LH stores and then induce frequent LH pulses
- Stimulation of follicular oestradiol production and rising oestradiol in circulation
- Switch to oestradiol positive feedback
- Induction of 1st gonadotrophin surge postpartum followed by ovulation and CL formation
Hormonal mechanisms which regulate the postpartum resumption of ovulation in cows:
The high steroid profiles before calving led to a downregulation of…
GnRH/LH pulses and also a chronic suppression of FSH levels
In postpartum, steroid removal will. Lead to…
Gonadotrophin recovery
Ovarian status of These hormones before parturition
-FSH
-LH
-astral & dominant follicles
➢Low FSH
➢Absent LH pulses
➢Small and medium
antral follicles only, no dominant follicles
Ovarian status of These hormones after parturition
-FSH
-LH
-astral & dominant follicles
➢FSH recovers very quickly
➢Rising FSH leads to follicle wave emergence
➢Dominant follicle selection within the first 2 weeks
Time to 1st ovulation depends on…
breed and (metabolic) health status determining pp LH pulsatility
Dominant follicle selected PP depends on support from?
LH pulses
In all cows during the postpartum (pp) period we see a quick/slow recovery of FSH and dominant follicle (DF) growth?
QUICK
During calving beef cows should have a good BCS. What happens if beef cows with low BCS goes through calving?
There are a lot more dominant follicle artesian going on (with the good BCS cow,the dominant follicle turnover came after third day, whereas with low BCS cow delay until first ovulation/dominant follicle turnover is very very long (around 140 days)
Before oestrus is expressed, what needs to be primed with progesterone?
Behavioural centres
First oestrus may be detected __ weeks postpartum in dairy cows. First oestrus may be detected __ weeks postpartum in crossbred suckler cows, but will be later in continental breeds
4
6
Dominant follicle growth is stimulated by… if these are too infrequent what occurs?
Frequent LH pulses
DF atresia occurs and a new wave emerges (DF turnover)
Which factors have the biggest affects on frequency of LH pulses postpartum (and therefore when follicle ovulation will occur) in;
1. Dairy cow
2. Beef suckler cow
Dairy cow->
-BCS at calving (not too important)
-negative energy balance (very important)- leads to BCS loss postpartum and loss of energy
Beef->
-BCS at calving- very important factor in influencing LH pulse
-maternal bond- calf presence- very strong negative regulator of LH pulses- those beef breeds with. Very strong maternal bonds will even more inhibited in. LH pulsitility
-suckling- small effect on LH pulses
-nutrition- minimal effect on LH pulses
If a cow has a very low NEB (negative energy Balance)
Will not resume ovulatory Activity for weeks after postpartum
What is negative energy balance in a cow?
When a cow is losing a lot of nutrients due to pregnancy/lactation but is not taken up enough food to counteract the loss of energy
(Diagram of graph on anki)
Postpartum anoestrus in suckled females depends mainly on (inhibitory of LH pulses)
presence of offspring, season and prepartum nutrition
Which factors have the biggest effect on LH pulsatility in the sow?
- Strong effect of the maternal bond in sows:
Presence of the offspring (and suckling) inhibit LH pulses - Protein nutrition during lactation: High maternal protein loss will delay time to 1st oestrus and ovulation after weaning
Delaying foal heat improves what in mares?
conception rates to breeding
What treatment is used to reduce LH pulsatility which therefore delays oestrus in the foal
Progesterone treatment- gives uterus a lot more time to involute and therefore fertility ^
Oestrus and ovulation in beef cows can be advanced by…
breaking the maternal bond, restricting suckling, or using hormone treatments
Which reproductive treatment hormones are used to induce 1st ovulation in beef cows
Progesterone treatment;
●GnRH (at start of a Progesterone treatment)
●eCG (at end of a Progesterone treatment)
How would you alter the animal husbandry of a beef. Cow to allow it to go into oestrus/first ovulation faster?
●En. rich diet after calving
●Short-term weaning (48h)
●Manipulation of suckling frequency
●Bull introduction
