THE CULTIVATOR 
47 
Dr. PLAYFAIRSS SECOND LECTURE. 
GRAZING AND FATTENING CATTLE. 
[In our last number we gave the first Lecture of Dr. 
Playfair, before the Royal Ag. Society of England, on 
the application of the principles of Physiology to the 
Grazing and Fattening of Cattle. We now give his se¬ 
cond and last Lecture on the same subject, which was 
delivered on the 8th Dee. last. We are indebted to the 
London Gardener’s Chronicle, for the reports of these 
Lectures.] 
Dr. Playfair, in commencing his second lecture, sta¬ 
ted that in the last lecture he had examined the nature 
of the food of animals; in this evening’s lecture, the pro¬ 
cess of growth and fattening in animals, would be more 
particularly considered. The health of an animal de¬ 
pends on the supply of nutriment being equal to the waste 
that is going on in the body. Healthy adult animals 
weigh as much at the end as at the beginning of the year, 
and this depended on their having had enough food to 
supply the waste going on in the system. In young and 
growing animals it is somewhat different; they require 
more supply than there is waste, because their bodies are 
constantly increasing in size. When animals are first 
born, the functions of organic life are chiefly performed. 
Respiration is at this time more active than in the adult. 
Nutrition is also more active. The food that nature sup¬ 
plies animals with at this period of their life, is well a- 
dapted to assist those functions. In the milk of animals 
is found nitrogenised matter for developing the system, 
and carbonised matter for supplying animal heat. The 
following is an analysis of the milk of a woman, a cow, 
and an ass, made by Dr. Flay fair: 
Woman. Cow. Ass 
Casein,. 1-6 4-0 1-9 
Butter,. 4-4 4-6 1-3 
Sugar,. 5-7 3.S 6-3 
Ashes,. 0-6 0-6 - 
Water, ••••••. S8-0 89-0 90-5 
The casein is the nitrogenised principle which affords 
nutriment to the muscular and other tissues. This is in 
greatest quantity in the cow. The butter and sugar are 
the combustible materials which by their combustion sup¬ 
ply heat to the body. The ashes consist of phosphate of 
lime and common salt, both of which materials are ne¬ 
cessary for the healthy function of the body. Thus, in 
milk we have all that is necessary for the growth of the 
body, and it is the type and representative of all food; 
for unless food contain the principles of milk, it is not 
fitted for the purposes of the body. Casein is the princi¬ 
ple of cheese. In its ordinary state, as made for the food 
of man, cheese contains both casein and butter. The 
stomachs of young animals are not adapted for separat¬ 
ing the nitrogenous principles from food, and the casein 
of milk is supplied to them ready separated. In the 
young ruminant, as the calf, the three first stomachs into 
which the food of the adult animals enter before it is di¬ 
gested, are not used at all. The milk passes at once in¬ 
to the fourth stomach. Hence the necessity of weaning 
these animals gradually, in order that their stomachs 
may be fully able to prepare the raw food for digestion. 
All food for weaning children, also, should be prepared 
on the model of milk, changing the relations of the ni¬ 
trogenised to the carbonaceous materials only as circum¬ 
stances require. In the milk of the cow, the carbonised 
materials are as two to one, but in the food of adult ani¬ 
mals they are as six to one. The large quantity of casein 
in milk is required for the rapid development of the bo¬ 
dy; the butter, a highly carbonised material, is required 
for supporting a large amount of animal heat. It is, con¬ 
sequently, a bad thing to feed calves on skim milk, as the 
butter and casein havm been removed, in the shape of 
cream. Earl Spencer, who is very successful in weaning 
his calves, feeds them first with new milk, then with 
skim milk and meal, the meal supplying the necessary 
azotised and unazotised materials, (azote and azotiscd are 
synonymous terms with nitrogen and nitrogenised.) In 
feeding young animals, as well as young children, they 
should have good food, and there should be no stinting 
them as to quantity. That farmer will lose in the end, 
who thinks to save his milk by stinting his calves. Arti¬ 
ficial food is sometimes made, and used as a substitute 
for milk. The Duke of Northumberland employs a mix¬ 
ture of treacle and oil cake, bruised flax, and hay. The 
fruit of Leguminosse contains casein; hence we may in¬ 
fer that peas and beans would be good food for calves. 
The difference between casein and albumen is, that the 
former is much more soluble than the latter, and proba¬ 
bly on that account more adapted for young animals. 
Beans and peas are known to be good things for growing 
pigs, whilst barley meal is good for fattening them. In 
the growth of young animals, as well as the fattening of 
adult ones, all exposui-e to cold, should be as much as 
possible avoided. Cold diminishes the vitality of the 
bod}q and whatever diminishe.s vitality, gives a prepon¬ 
derance to chemical action in the body, and injury of 
some kind is the result. Exercise is also necessary for 
the rearing of young animals, although it should be avoid¬ 
ed in fattening. In order to develope the calf and the 
lamb, they should be allowed plenty of exercise; but in 
fattening another object is to be gained. All motion 
consumes something in the body, therefore motion is so 
much loss of material in the fattening an animal. In the 
same manner, exposure to cold, as was proved by the 
experiments repeated in the last lecture, was a positive 
loss in the fattening of animals. Stall feeding is benefi¬ 
cial, both on account of warmth and quietude. The pri¬ 
mary cause of all this waste is the supply of oxygen; 
whatever increases the supply of oxygen, increases the 
waste of the body, and the necessity for supply. Fatting 
animals are often kept in the dark. Darkness favors 
sleep, and sleep quietude. It was thus that darkness was 
favorable to fattening. A case was related of a pig that 
was placed in a box in the dark, and the sides stuck full 
of pins, to prevent the animal moving in any manner, 
and the animal quickly got fat. The fattening of orto¬ 
lans, in Italy, illustrated this point. The ortolan is a 
bird that takes its food at dawn of day, and the breeders 
of these birds take advantage of this, and shutting them up 
in a dark room, they contrive to let in the light four or 
five times a day, and to supply the birds with plenty of 
food. The birds, at every admission of light, thinking 
the time is come to eat, take their usual quantity of food, 
and on the light being withdrawn, they fall asleep, and 
in this manner they rapidly get very fat. Sleepy, good 
natured pigs fatten fast; but active pigs, as the Irish, ne¬ 
ver get fat all. A question may still arise as to whether 
it is better to feed animals in stables or small yards. The 
manure of the latter is stated to be better, and there is 
no doubt of this, but then the gain of the manure is lost 
in the fattening of the animal. Manures will also vary 
in value, according to the food animals take. The ma¬ 
nure furnished from cattle eating turneps, was nothing 
like the value of the manure furnished by cattle eating 
linseed cake. Feeding cows for the dairy, was a subject 
worthy great attention. In the first place, it seemed ne¬ 
cessary to supply cows with food containing potassa. 
Potassa converted albumen into casein — that is, it made 
it soluble—and soluble albumen is casein, and casein is 
the most important constituent of milk. It might be a 
question as to whether casein was introduced directly in¬ 
to the blood from the food, or whether it might not be 
the result of the destruction of the already formed tis¬ 
sues. Animals fed in the open air, gave milk with more 
casein than animals fed in close places. The lecturer 
found more casein in the milic given in the evening after 
the cows were out all day, than in milk given in the 
morning after the cows had been standing all night. The 
tissues are consumed by exercise, and thus yield the ca¬ 
sein. Parturition makes a great demand on the powers 
of the system, and Braconnot found that the milk of a 
cow directly after calving, contained 15 per cent of ca¬ 
sein, a much larger proportion than ordinary. The al¬ 
kalies, set free by motion, convert the albumen into ca¬ 
sein. The butter in milk is not introduced, as Dumas 
asserts, with the food. It is formed from the starch that 
exists in the food. The only change necessary to convert 
starch into fat, is the abstraction of oxygen. The sugar 
of milk is a peculiar compound; it consists of starch, 
with two proportions of water. The state of the mind 
affects the secretion of milk. In woman, anger, sorrow, 
and anxiety, affect their milk so much, that chikken suf¬ 
fer very much, or even die, from the effects of partaking 
of it. For the same reasons, cows should be kept free 
from all kinds of irritation. When at a distance, they 
should be allowed to walk to the milking place at their 
own pace, and never be driven. Exercise is bad for the 
butter. Where much exercise is allowed, the produce 
of butter is small; this arises from the oxygen consum¬ 
ing the carbonaceous material that would otherwise be 
secz’eted in the milk in the form of butter. In summer, 
flies torment cows in the day, and they do not yield so 
much butter. This may be remedied by sending the 
cows into the fleld at night, and keeping them at home 
in the daj^; but this must only be done in summer, as it 
would be a bad system during cold nights. Stall fed 
cows produce most butter; and where butter is the ob¬ 
ject, cows should be turned into the richest pastures. 
With regard to the pastures for producing casein, or 
cheese, there is a very general impression that poor land 
is best adapted for producing cheese. In general, in 
cheese districts the pastures are poor. H is, perhaps, the 
exercise which the animals take on poor land, in order 
to obtain food, that (for reasons before stated,) develops 
the casein in the milk. Stall fed cows yield much less 
casein than those fed in pastures. Cows that are requir¬ 
ed to yield cheese, should not be kept poor, but it is de¬ 
sirable that they should have to travel some way for their 
food. Some foods that animals eat, flavor their milk, as 
Swedish turneps; buttercups color it. Many plants may 
affect cows when taken with their fond. The lecturer, a 
short time since, was in company with Dr. Daubeney, 
and Dr. Buckland, in Somersetshire, where they met with 
a farmer, who stated, as a singular fact, that he had two 
pastures, the one of which, when he turned his cows in, 
they became purged; and the other, when he turned 
them in, produced constipation. The farmer could not 
account for this; but Dr. Daubeney, on examining the 
fields, found that the one which purged the cows, con¬ 
tained a large quantity of purging flax (Linum catharti- 
cum,)with the, grass, whilst the other contained an equal 
abundance of the common tormentil, or septfoil, (Poten- 
tilla tormentilla,) a very astringent plant, which at once 
accounted for their peculiar action. In Scotland, they 
procure good milk from stall fed cows, by feeding them 
upon malt refuse, and bean and pea meal, and giving 
them beer to drink. The malt refuse supplies the mate¬ 
rials for butter and sugar, the beans and peas the casein, 
whilst the beer keeps up the animal heat. Water would 
carry off the heat, besides acting injuriously by dissolv¬ 
ing the blood globules. 
_ The principles of chemistry will also enable us to as¬ 
sign the causes, and in some measure to prevent the oc¬ 
currence, of diseases among cattle. What is called con¬ 
sumption, rot, foot rot, &c., in cattle, arises from a slow 
combustion or destruction of their tissues, by the agency 
of oxygen. The same process goes on in vegetables; 
and it is well known that this process can be communi¬ 
cated from one vegetable to another, as from an apple to 
an orange, &c., and decaying vegetable matter will com¬ 
municate this process to an animal. These diseases al¬ 
ways occur amongst animals closely kept, where there 
is much decaying vegetable matter about. Animals ex¬ 
posed to drafts do not take these diseases; the draft car¬ 
ries off the decaying ferment. When this process is es¬ 
tablished in the intestines, it produces diarrhosa, and this 
probably arises from animals consuming bad food. Red 
water and black w'ater, arise from the same disease ex¬ 
tending to the kidneys. Rot in the feet, comes on from 
the same cause. It always occurs at that season of the 
year when vegetable decomposition is greatest, and oc¬ 
curs to the greatest extent where animals are obliged to 
tread on decaying vegetable matter. The treatment of 
these diseases should be by anti-putrescent materials, 
such as chlorine and the emjiyreumalic oils, &c. These 
will disinfect the stalls or sheds where animals are kept. 
Dr. Playfair then stated that he had a few observations 
to make on the character of the internal and external 
structure of the organs of animals, in order to arrive at a 
knowledge of them as indications of their capacity for 
fattening and reaching an early maturity. These obser¬ 
vations he wished to be put to the test of experiment, as 
he was aware that some of them were opposed to gene¬ 
rally received views. First, with regard to internal 
structure, which was the most important. It was gene¬ 
rally considered that animals with large chests fattened 
best, and it was supposed that all animals with broad 
round chests had large lungs. But this is not the case. 
Sheep have round chests and small lungs. Horses have 
narrow chests and large lungs. South Down sheep have 
narrower chests than Leicester sheep, yet they have the 
largest lungs. The Leicester sheep are known to fatten 
soonest. He spoke hereof the aboriginal breeds of these 
animals. He had asked butchers, and they were unani¬ 
mously of opinion that the fattest cattle had small lungs 
and small livers. Now this was a necessary consequence 
of the preceding principles. Where most oxygen was 
taken into the system, there would there be the greatest 
destruction of carbon, and consequently less carbonaceous 
material deposited in the form of fat. If two pigs had 
the same quantity of food, and one had lungs of double 
the capacity of the other, that pig would only appropri¬ 
ate half as much of its food in the form of fat. Milk 
with much butter in it, was known to be produced by 
cows with small lungs. The same held good with re¬ 
gard to the liver; where there was a large liver, there 
would be a large secretion of bile, and a large destruc¬ 
tion of carbonaceous matter. If two animals ate CO lbs. 
of food, and one secreted 37 lbs. of bile, and the other 
only 30 lbs., the food that was not formed into bile would 
be converted into fat; hence the gain on the animal with 
a small liver. With regard to external signs, small bones 
indicated a delicacy of constitution, smallness of lungs 
and liver, and a tendency to fatten rapidly; whilst large 
bones indicated just the contrary. The “mellow” feel 
of an animal depended on the resiliency of the cellular 
tissue of the animal, the tissue in which the fat is depo¬ 
sited. When there is much mellowness, it arises from 
the blood being easily pressed from one part of the cel¬ 
lular tissue to another, and indicates a susceptibility to 
fattening. The reason why animals get more rapidly 
fat at the end of their feeding season is, that the fat ac¬ 
cumulating in the abdomen, presses upon the diaphragm 
and abdominal muscles, and thus prevents the more com¬ 
plete action of the lungs, and consequently the destruc¬ 
tion of the carbonaceous material, by the inhalation of 
oxygen. The fat also prevents,the oxygen being ab¬ 
sorbed by the skin, and diminishes by its pressure the 
capacity also of the liver, and thus also adds to the fat¬ 
tening process. Large ears indicate a general coarse¬ 
ness of bone and muscle, and the same condition of lungs 
and liver, and are thus indicative of a small capacity for 
fattening. There were other indications which might 
be referred to, but the lecturer hoped these hints would 
be sufficient to set inquiry afloat on a very important sub¬ 
ject. He apologized for W'hat he considered the incom- 
jilete evidence he had brought forward to establish some 
of his views, but stated he had experiments in progress, 
which he hoped would throw more light on many of the 
more obscure points to which he had alluded. 
Lord Spencer proposed a vote of thanks to Dr. Play¬ 
fair, for his lectures, and stated how much gratified he 
had been in listening to them. He hoped agriculturists 
would see from these lectures, the great benefit likely to 
accrue to them from a knowledge of the principles of 
the science of physiology and chemistry. Mr. Pusey 
seconded the motion. Dr. Playfair, in returning thanks, 
stated that he had drawn up a series of statistical tables 
for circulation amongst butchers, for the purpose of gain¬ 
ing information on the internal structure of the animals 
which they slaughtered. 
Address of the Hon. Garnett Andrews _ We 
have received a copy of the Address delivered by Judge 
Andrew’s, before the Planter’s Club of Hancock co. Geo., 
Nov. 4th, 1842. The historical progress of Agriculture, 
the advances it is making in the southern states, the im¬ 
provements in the agricultural processes, stock, &c. of > 
the day, and the high standing of the farmer, andthepo- 
sition he should h(Md, are well and forcibly given, and 
we think cannfit fai] to exert a most favorable influence 
wherever the addre,ss is read. This address is only one 
of the many proofs we are almost daily receiving of the 
attention that an improved Husbandry is leceiving at the 
South. 
