Quiz 3 Flashcards

1
Q

What is aquaculture?

A

The farming of aquatic organisms, including fish, molluscs, crustaceans, and aquatic plants

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2
Q

In 2010, what percentage of the world’s fish food production for human consumption did aquaculture make up?

A

47%

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3
Q

Who are the world’s leaders in aquaculture?

A

Asia (China)

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4
Q

What are the top 3 world aquaculture fresh water fishes in 2010?

A

Silver & bighead carps, Indian major carps, and grass carps (other than carp (cyprinids) lower on the list catfishes, bass and perch, snakeheads, characins)

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5
Q

What are the top 3 world aquaculture diodromous fishes in 2010?

A

Atlantic salmon, milkfish, rainbow trout

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6
Q

What are the top 3 world aquaculture marine fishes in 2010?

A

Jacks, pompanos & mackerels/ Drums and croakers/ Gilthead seabeam

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7
Q

Describe extensive aquatic systems

A

Low cost, natural containment, simple structures, low control, seed stock from nature, no monitoring of water quality

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8
Q

Describe intensive aquatic systems

A

High cost, fabricated, concrete, cages, etc, domesticated seed stock, regular monitoring of water quality, feed source is commercial pelletised

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9
Q

Major aquaculture in Australia

A

Pearl oysters & Barramundi & Prawns, silver perch, murray cod, mussels, Abalone, SB tuna, yellowtail kingfish, scallops, rock lobster

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10
Q

In the salmon production cycle, where do salmon lay their eggs?

A

Freshwater

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11
Q

What are static pond systems in aquaculture?

A

Earthen impoundments, enclosed waterway in a valley or stream bed, natural light, soil important, lined with impermeable sheeting

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12
Q

What species are grown in static ponds in Australia?

A

Barramundi, murray cod, silver perch, golden perch, prawns

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13
Q

What are tank systems in aquaculture?

A

Second to ponds as the most commonly used for aquaculture, generally above ground on solid base indoors and outdoors, allow the use of land normally unsuitable for aquaculture, no contact to the surrounding soils, range of sizes

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14
Q

What species are grown in Australia in tanks?

A

Barramundi, Southern bluefin tuna, yellowtail kingfish, murray cod silver perch, golden perch, rainbow trout, atlantic salmon, abalone, prawns, oysters

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15
Q

What is a recirculation aquaculture systems (RAS)?

A

Intensive, rely on very little water exchange daily, significant risks, highly controlled environment, “closed” systems, generally high capital investments, usually run high stocking densities (>50 kg/m^3), dissolved oxygen first limiting factor, ammonia usually 2nd limiting factor, must strictly maintain water quality including temperature, fish housed in tanks

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16
Q

What are some critical equipment for a RAS?

A

Back up generator, biological filters (with sufficient capacity), oxygen supply (often liquid oxygen), protein skimmers, pumps, alarms

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17
Q

Open sea cages

A

Generally good water flow but where cages sited (moored) very important, must find site with adequate exchange of high quality water but also protected, stocking densities up to 10-15 kg/m^3, species grown in sea cages in Aus: atlantic salmon, rainbow (“ocean”) trout, yellowtail kingfish, southern bluefin tuna, barramundi, abalone

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18
Q

What is the most commonly farmed deer in Aus?

A

Red deer (Reindeer second most commonly farmed) (mostly in NSW and VIC)

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19
Q

What country has the world’s largest number of farmed deer?

A

NZ (1.2 million approx 2009)

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20
Q

What do Fallow Deer look like?

A

Bambi

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21
Q

What do red deer look like?

A

Red with large antlers

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22
Q

What do Wapiti look like?

A

aka Elk (think of WA state)

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23
Q

What comes out of a deer production system?

A

Venison, velvet, skin tails, pizzles, sinews, prices

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24
Q

What are the temperate deer species?

A

Fallow, red, elk (wapiti)

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25
Q

What are the tropical deer species?

A

Rusa, chital/sambar/ hog/ white-tail/blackbuck

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26
Q

What are some facts about temperate deer species?

A

Tight photoperiod for antler growth and reproduction, calve nov/dec, wean before rut (autumn), winter weight loss, double coat/ open coat, strong dominance hierarchy, seasonal venison

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27
Q

What are some facts about tropical species?

A

Much less photoperiod compared with temperate spp, calve in late autumn/winter, weaning variable, no winter coat, venison not seasonal, less aggression between stock

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28
Q

Stocking rates of fallow doe, red hind, rusa hind (females)

A

2 DSE (fallow dow), 3.5 DSE (red hind), 3 DSE (rusa hind)

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29
Q

When does velveting occur in red/elk, fallow, and rusa?

A

Nov/dec (red/elk), fallow (dec/jan), and rusa (dec/ june)

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30
Q

When does calving occur in red, fallow, rusa?

A

Late nov/ dec (red), fallow (dec/jan), and rus (self/3 months)

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31
Q

Male reproduction with deer

A

Neck hypertrophy, roar, antler calcification, aggression/ territory marking, 30% body weight loss, march- july

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32
Q

Male reproduction deer species differences

A

Less photoperiod influence, reds move with and protect harem, fallow occupty stationary territory with harem

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33
Q

Female reproduction deer species

A

Seasonally polyoestrus with very distinct photoperiod effects in temperate species, puberty reached at 15 months (second autumn), fertility peak at 5 yrs, 2nd and subsequent offspring heavier, twins rare, calf “stashed” for first few days

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34
Q

Seasonal advancement in female deer

A

hormonal manipulation by P4 implants with PMSG, oral melatonin, daily yarding to dark pens

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35
Q

Pregancy diagnosis in deer

A

Trans-rectal ultra-sound, 30 days onwards +/- 10 days foetal age, double progesterone

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36
Q

Velvet harvesting

A

Amputation of live antler prior to calcification from male deer, must be carried out under vet supervision with appropriate analgesia or by a farmer accredited through the National Velvet Accreditation Scheme

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37
Q

Antlerogenesis

A

Annual casting of buttons (or antlers) and regrowth and calcification, increased daylight–> decreased testosterone–> cast and new growth, decreased daylight–> increased testosterone–> shedding of velvet and calcification

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38
Q

Velvet casting and regrowth when?

A

July/ August (regrowth sept/ january 3-4 months)

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39
Q

Primary harvesting of velvet?

A

October/ November

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40
Q

Velvet maturation?

A

January/ February (3-4 months)

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41
Q

Velvet names from bottom to top of antler (on its side)

A

Brow tynes, bez tynes, trez tynes (all on the main beam) then the royal tynes (if present- splits of the trez tynes as a continuation of main beam)

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42
Q

In what areas can a vet advise a farmer about drought?

A

Nutritional assessment and feeding of stock, feed budgeting, disease management, animal welfare and humane destruction, and farm economics

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43
Q

What is a “drought?”

A

A period of acute water shortage, due to serious or severe rainfall deficiency over several months. (“serious” and “severe”- rainfall over the last 3 months have been in the lowest 10% and 5% of longterm recorded rainfall figures)

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44
Q

Green drought

A

Pasture is growing because of recent rain (i.e. is green, not senescent and dry) but does not meet the needs of livestock at a time when it normally should

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45
Q

Australian Govt. Exceptional Circumstances (EC) classification to ID rare and severe events (defined?)

A

Rare is 1 in 20 year event and severe is more than 12 months or at least 3 consecutive dry seasons

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46
Q

In a drought animal consequences?

A

Reduced weight gain or faster weight loss–> effects on lactation, wool growth, muscle/ fat growth; prolonged absence of green feed can lead to vitamin deficiences; prolonged grain supplementation can lead to digestive (rumen) upsets or mineral imbalances

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47
Q

In drought environmental consequences?

A

Overgrazing of pastures: excessive grazing damages/ reduces plants–> reduced seed and vegetative mass available to regrow and recolonize bare areas after the drought breaks; loss of vegetative ground cover can lead to soil erosion (loss of fertility); water quality may be degraded (dams contaminated with eroded topsoil, waterway erosion/ degradation by stock, etc.)

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48
Q

In drought farm business consequences?

A

Increased cost: supplementary feed, replacement stock are expensive when the drought breaks (demand increase); decreased income: lower liveweight and price/kg for sale stock, reduced wool growth and milk production, fewer animals left to restore future production & earning potential following animal sales or decreased reproduction during drought

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49
Q

Drought management options (4)

A
  1. Total or partial destocking
  2. Feed all stock for survival
  3. Agistment (take cattle to graze elsewhere if less than supp feed cost)
  4. Production Feeding
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50
Q

What is typically the cheapest energy supply on a cent per megajoule basis in AUS?

A

Cereal grain

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51
Q

Survival feeding amount/ week (kg) of dry sheep 1 DSE (45 kg)

A

4 kg per week (5 MJ/ME/DSE/day) (20% roughage in diet to maintain rumen health- feed 2-3 times per day for shy feeders sake)

52
Q

Survival feeding amount/ week (kg) of dry cow

A

17 kg per week (33 MJ/day) (20% roughage in diet to maintain rumen health- feed 2-3 times per day for shy feeders sake)

53
Q

Why would you feedlot animals during drought?

A

To save pastures. Confinement of some/ all mobs of stock to small areas is based on reducing soil erosion and saving improved pastures, which would otherwise be severely affected by overgrazing.

54
Q

In a drought, when does the risk of soil erosion increase, at what percent of bare ground (esp. in hilly or sandy paddocks)?

A

> 30% (generally destock if > 20-30% bare area

55
Q

What stocking rate in feedlot for sheep / ha?

A

2000/ha (pens of 1000/ 0.5 ha) (not optimal for growth but feeding easier and more efficient and saves the rest of the farm).

56
Q

What trough space per sheep?

A

10 cm per sheep trough space

57
Q

What percent of water for sheep per day?

A

10% of animal bodyweight per head per day

Sheep- 5 L/ day
Cattle- 50 L/day

58
Q

Main diseases associated with drought

A

Ineffective supplementation, pulpy kidney (intestinal overgrowth of Clostridium perfringens E with ++ carb diet and toxin release), acidosis (overgrowth of acid- producing microflora ++ CHO diet), calcium deficiency/ imbalance (cereal grains high P/low Ca–> prolonged feeding depletes body Ca), vitamin E deficiency (absent in dry feeds, oxidants from grain feeding increase risk), water quality (increased salinity of groundwater, organic matter contamination, and algal overgrowth of dams), animals released too fast onto pastures after break (toxic weeds can dominate over-grazed pastures)

59
Q

Feed and management practices during drought

A

Monitor condition score, separate shy animals, booster vaccine pulpy kidney before they enter feedlot, gradual grain introduction over 2-3 weeks, 1.5% CaCO3 to all cereal grains, supplement every 6 weeks with vitamin E rich feeds (not dry), monitor water quality, release on full stomach, phase out supplement over 1 week after release

60
Q

Survival feeding amount/ week (kg) of dry cow 9 DSE

A

9* 5= 45 MJ/ME/cow/day

61
Q

Wildlife definition

A

Any animal of a vertebrate species, which is indigenous to Australia or its territorial waters.
Introduced species are not wildlife- rabbits and foxes should not be treated and released

62
Q

What are the three acts of parliament which cover the dos and don’t of wildlife?

A

The Prevention of Cruelty to Animals Act 1986
The Wildlife Act 1975
The Veterinary Practice Act of 1997

63
Q

What does The Wildlife Act 1975 in Victoria (Act of Parliament) state?

A

Vets can hold wildlife for purposes of diagnosis and treatment. It is an offence not to render assistance, wildlife shelters can hold wildlife for rehab and foster carers too, wildlife license holders can keep designated species for private purposes, wildlife can only be taken from the wild under the Minister’s okay (research and licensed wildlife dealers), endangered species and select species (seals, platypus, penguins, koalas, birds of prey) are subject to legal restrictions and advice should be sought from DEPI, cannot pass wildlife on to unauthorized people

64
Q

DSE?

A

Dept. of Sustainability and the Environment (can also be informed of the case but not required)

65
Q

Rehabilitation of Wildlife

A

Restore to a former way of life. Reintroduce- establish in former habitat. (depending on species reintroduce, introduce, or translocate)- translocation is not a humane method of dealing with problem possums

66
Q

What are the two main threats to wildlife worldwide?

A

Loss of habitat and introduction of exotic species (prey on or compete for resources with native species)

67
Q

Who monitors wildlife, especially for the potential introduction of exotic diseases?

A

Animal Health Australia (semi-govt. institution)

68
Q

Why does the Australian Bee Industry exist?

A

Honey is a food product, honey bees contribute to the productivity of many horticultural crops by providing essential pollination services that improve crop yield and quality

69
Q

What is the value of the honey bee industry?

A

$100 million. BUT likely to be several billion since approx 65% of horticultural and agricultural crops produced in AUS require pollination services from honeybees

70
Q

Stats on the honey bee industry

A

10,000 registered beekeepers, 1700 commercial apiarists with more than 50 hives, 600,000 hives in AUS, 30,000 tonnes of honey each year

71
Q

What percentage of honey is exported?

A

25-30% (30-35%)

72
Q

When and where did the commercial honey bee come from?

A

Introduced in 1922 from Europe

73
Q

What is the best known bee in AUS?

A

Non-native yellow-brown commercial honey bee (European Honey Bee- Apis mellifera)

74
Q

How many species of native bees in AUS?

A

over 1500

75
Q

What are the three main threats facing the honey bee industry?

A

The introduction of exotic pests and diseases, particularly the parasitic mite Varroa destructor; access to natural resources; contamination and mislabelling of Australian honey bee products

76
Q

What are other pests and diseases aside from Varroa that could impact the honeybee industry?

A
  • Tropilaelaps mite, tracheal mite, Braula fly, American foulbrood (Bacillus larvae)- spore forming bacteria, European foulbrood- a bacteria, Leafcutter bee chalkbrood, Small hive beetle, stonebrood
77
Q

National Sentinel Hive Program (NSHP)- what is it?

A

Est. in 2000 to enhance post-border monitoring and early detection for exotic pests of honey bees in AUS and is administered by Animal Health Australia. Located at strategic sea and airports where exotic pests of bees may be encountered.

78
Q

What govt department in VIC overseas animal health?

A

Dept of Env. and Primary Industries

79
Q

Who works to prevent wildlife extinction in AUS and NZ and the South Pacific? Also, represents zoos and aquariums

A

The Zoo and Aquarium Association (ARAZPA)

80
Q

What is CITES?

A

Convention on International Trade in Endangered Species of Wild Fauna and Flora- international agreement between govts- aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival

81
Q

What roles do zoos, wildlife parks and aquariums provide to our society?

A

Education of the public, contribution of species conservation, research of health, biodiversity conservation

82
Q

Major concerns owning illegal exotic pets

A

Environmental pests if they escape and introduction of exotic diseases

83
Q

Why is Vitamin D critical?

A

Maintenance of calcium and bone metabolism throughout an animal’s life. Sunlight is the major source of vitamin D.

84
Q

What occurs in growing birds with a deficiency in either calcium or phosphorous?`

A

Lack of normal skeletal calcification. Rickets is seen mainly in growing birds, while calcium deficiency in laying hens results in reduced shell quality and osteoporosis. This depletion of bone structure causes a disorder that is commonly referred to as “cage layer fatigue”

85
Q

What is rickets?

A

Most commonly in young meat birds; the main characteristic is inadequate bone mineralization. Calcium deficiency at the cellular level is the main cause, althought a diet deficient or imbalanced in calcium, phosphorous, or vitamin D3 can also induce this problem.

86
Q

What are the meat lines of chickens?

A

Plymouth Rock and Cornish or Indian Game (Black and white/ blue and brown)

87
Q

Australian’s eat how much chicken per year?

A

4.4 kg in 1950 to 38 kg in 2006

88
Q

How long is incubation of fertile eggs?

A

21 days incubation

89
Q

Free Range Broiler production- what percentage of Vic’s production?

A

10% (40 of 220 farms)

90
Q

How long are birds grown (growth cycle)?

A

5-8 weeks (approx 5.5 batches annually)

91
Q

How are broilers killed?

A

Electrical stunning or gaseous stunning using carbon dioxide

92
Q

The broiler growth curve at 56 days is about what weight in grams?

A

3500 grams

93
Q

What is a good performance mortality range for a broiler batch?

A

2-3 % (1.5-6% range- more mortality in week one)

94
Q

Causes of mortality in broilers

A

Yolk sac infection (1-5 days/ bacterial disease), acute death syndrome, ascites, lameness and skeletal disease, respiratory disease and bacterial septicaemia

95
Q

What are Rachitic Disorders (Rickets) in broilers and when does this often occur in broilers?

A

Rickets defective mineralization of bones in immature mammals due to deficiency or impaired metabolism of vitamin D (develop within 7-14 days of age). Calcium deficiency at the cellular level is the main cause and an imbalance in calcium, phosphorous or vitamin D adds to the problem.

96
Q

What heart conditions and when do they occur in broilers?

A

ventricular englargment 5-14 days of age, dilated right ventricle (same time span)

97
Q

When does ascites develop in broilers? How is it prevented?

A

14-35 days. Warm brooding (sit on eggs), low dietary sodium, correct coccidiostat (antiprotozoal agent)

98
Q

When are pullets (females less than one year old) reared (egg laying)?

A

day old to 16 weeks

99
Q

When is sexual maturity for egg laying hens?

A

17-18 weeks

100
Q

What is the mortality percent in the rearing phase in egg layers?

A

2-3%

101
Q

What is the hen production of eggs in 12 months?

A

250-330 eggs

102
Q

When are egg laying hens culled?

A

68-72 weeks of age (1.5 years old)

103
Q

What is the mortality percent in the laying phase?

A

2-15% (3% good performance)

104
Q

What is an aviary?

A

Limited use commercially in Aus, European housing system, high rise barn system combined with free range, 120,000 birds plus free range

105
Q

What are advantages of barn laid commercial farms?

A

Elimination of wild birds, protection from predators, moderate economies of scale, birds can nest, dust bathe, perch and move around freely

106
Q

What are disadvantages of barn laid commercial farms?

A

social competition increased, reduced production in comparison to cages, floor eggs, increased mortality compared to cages

107
Q

What occurs with under weight flocks of egg layers?

A

Lower egg production, high incidence of blood stained eggs (cloacal haemorrhage) (predisposes cannibalism in many spp), higher mortality

108
Q

What is trauma/ cannibalism correlated with?

A

oviduct impaction, egg peritonitis/ salpingitis (not observed in single bird cages)

109
Q

Cannibalism in the fowl caused by?

A

Innate biology, learnt behaviour in young chicks, high temp, high humidity, high light intensity >30 lux, sudden increases in light intensity, pica or nutrient deficiencies, haemorrhage & tissue trauma

110
Q

Options for egg layers to reduce cannibalism

A

body weight management and control of light intensity; light management and no beak trimming; light management and day old trim using infra red; light management, day old trim, and second hot blade trim; no light management, day old trim, and second hot blade trim

111
Q

Increased daylight means what for antlers?

A

cast and new growth (decreased testosterone)

112
Q

Decreased daylight means what for antlers?

A

cast velvet and calcification (increased testosterone)

113
Q

Fish are most highly sensitive to what?

A

Temperature and dissolved oxygen of water

114
Q

Fish have a substantially higher requirement for what than most land mammals?

A

Protein. However, req. reduces as fish age.

115
Q

How do fish do in terms of FCR?

A

Feed to body mass conversion- highly efficient

116
Q

Why is Vitamin D necessary?

A

Maintenance of calcium and bone metabolism.

117
Q

What products are being produced by the smallholder sheep and goat farmers in the CDZ?

A

Meat from young animals, meat from culls, breeding females and males sold to other farmers, skin, manure for fertilizer

118
Q

What are the key factors influencing the level of this production in the myanmar sheep and goat farms?

A

Nutrition- young animals need good quality feed to achieve greater growth rates; ditto females and BW and growth of young preweaning

Genetics- may influence growth rate, final body size, FCR efficiency, current system may be prone to inbreeding and hence poor productivity

Management- time of lambing and hence female and offspring nutrition, potential environmental stressors at some times of year, weaning age and overall nutrition of progeny, essentially no preventive health currently practiced

119
Q

What other products could be generated?

A

Milk, fibre

120
Q

What are some unique considerations with small ruminants in the tropics?

A

Summer heat rams are less active and heat related fertility problems

Heat stress during pregnancy lower lamb birth weights and therefore less survivability (autumn joining is better for this problem)

Lambing before onset of summer heat

In QLD- autumn is good quality feed (so spring/ summer joining)

121
Q

How useful are carbohydrates to fish?

A

Non essential nutrient for salmonids, has useful protein sparing effect, in general warm water species utilize carbs better compared with cold water species- related to complexity of carbohydrate

122
Q

What happens to fish if we have too much energy in their diets?

A

Too much energy- fish eat less, lay down fat

123
Q

What happens to fish if we have too much protein?

A

Expensive protein ends up being used for energy

124
Q

Proteins derived from fish are what percentage digestible for fish?

A

85% +

125
Q

What is a FCR?

A

Feed Conversion Ratio. Amount of feed a farmer feeds their fish (in kg) divided by the amount the fish grow (in kg)

126
Q

What factors effect FCR?

A

Feed quality, feed management, feed storage, stocking densities, egg quality (broodstock), strain/ species effects, temperature, health. 90% of variance in specific growth rate (SGR) and FCR is due to errors in judgement in daily ration.

127
Q

Problems with fish, what should you check?

A

Genetics, Feed management, water quality, composition of diet, disease issues, husbandry (i.e. stocking densities)
* If overfeeding was the issue, then the reason for the increased FCR may simply be because a lot of the feed is not being eaten by the fish and therefore going straight into the environment.