· a production manager in one of the most important spanish swine production companies. for...

Medicina pediátrica en pequeños animales

PRESENTATION BROCHURE

Lactation

HUSBANDRY AND MANAGEMENT PRACTICES IN FARROWING UNITS II

Emilio Magallón Botaya (Coordinator)Alberto García Flores

Roberto Bautista MorenoBoris Alonso Sánchez

José Ignacio Cano LatorreSilvia Almenara Díaz

Patricia Prieto MartínezPablo Magallón Verde

After providing a comprehensive review of the fundamental aspects of farrowing (physiology, facilities, organisation, etc.) in the fi rst volume, in this second volume the authors focus on the next phase, lactation. From the technical and physiological aspects that affect both the mother and the piglet, to production targets, feeding, health programmes on the farm or personnel management. These are topics that will undoubtedly be helpful in the daily practice of professional veterinary surgeons.

As in the previous volume, the authors have achieved a very practical book with rigorous contents, based on their experience and technical literature, accompanied by a large amount of visual material to complement the information given.

HUSB

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Emili

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After providing a comprehensive review of the fundamental aspects

of farrowing (physiology, facilities, organisation, etc.) in the first

volume, in this second volume the authors focus on the next phase,

lactation. From the technical and physiological aspects that affect

both the mother and the piglet, to production targets, feeding,

health programmes on the farm or personnel management. These

are topics that will undoubtedly be helpful in the daily practice of

professional veterinary surgeons.

As in the previous volume, the authors have achieved a very

practical book with rigorous contents, based on their experience

and technical literature, accompanied by a large amount of visual

material to complement the information given.

Husbandry and management practices in farrowing units II. Lactation

Lactation








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Author: Emilio Magallón (coordinator), Alberto García, Roberto Bautista, Boris Alonso, José Ignacio Cano, Silvia Almenara, Patricia Prieto and Pablo Magallón.

FormAt: 17 x 24 cm.

Number oF pAges: 200.

Number oF imAges: 150.

biNdiNg: Hardcover.

retAiL priCe

55 €

Presentation of the book

In the past few years, the pig production industry in general and sow farms in particular have undergone great changes: increase in the average size of farms, introduction of new, more prolific genetic lines, improvements in health, better qualified professionals, chan-ges in feeding patterns, better facilities, etc.

As a consequence of these significant changes, productivity on sow farms has increased to such an extent that it is necessary to apply new management and husbandry practices in all the areas of production, but particularly during farrowing and lactation. Sows farrow many more piglets, but with a lower birth weight. Furthermore, the new genetic lines of sows are thinner, have greater mammary development, a greater milk production and require a good body condition to rear their piglets. This entails longer and more productive lactations with changes in the diets, facilities, sow and piglet management practices, per-sonnel management, etc.

With this book, the authors aim to provide an update on the new husbandry and manage-ment practices in farrowing units, with a focus on lactation.

The book starts with a reminder of the technical and physiological aspects of lactation and continues with the environmental control of farrowing units and feeding of the lacta-ting sow and suckling piglet. It then focuses on sow management during this phase, with an emphasis on fostering techniques and management practices after weaning. It also provides information on health programmes and personnel management, as well as on production targets during lactation.

In the authors’ opinion, there was a need for a book that would review the new ways of working and managing modern sow farms. A book with rigorous, scientific grounds that would also be pleasant to read. This is why numerous images, diagrams and summaries have been included.

This book has been written by professionals in the sector who are very involved in the daily work on sow farms. They have therefore chosen to avoid overly technical terms and have used an accessible and simple language.

This book is aimed at a very heterogeneous audience, from veterinary professionals to students, unit supervisors and farm workers specialised in farrowing unit management, and, of course, to all those veterinary or animal husbandry professionals who would like to know the latest innovations in farrowing unit management on modern sow farms in a quick and direct manner.

Finally, it should be remembered that this book is the second part of a work on husbandry and management practices in farrowing units. The first volume, “Husbandry and mana-gement practice in farrowing units I. Farrowing”, addressed all the questions related to farrowing and this second volume will deal with those related to the lactation period.


The authors

Emilio Magallón Botaya (coordinator)Emilio Magallón Botaya graduated in Veterinary Medicine in 1978 from the University of Zaragoza, Spain, with a specialisation in Animal Production and Agricultural Economics.

After starting his professional career as a large animal veterinary surgeon, he started wor-king in the swine sector in 1981; initially as a technician, later as a team leader and then as a production manager in one of the most important Spanish swine production companies.

For several years he was an associate professor of Swine Production at the Faculty of Veterinary Medicine of the University of Zaragoza. He also participated as a professor of Economic Analysis Applied to Swine Production for a Master’s degree programme in Ani-mal Production and Health organised in partnership by the universities of Zaragoza, Léri-da, Barcelona and Madrid.

He has participated in several research projects related to the swine sector and is currently co-leading a project for the genetic improvement of swine funded by the Spanish Centre for Industrial Technological Development (CDTI), in collaboration with the animal production area of the Spanish Institute of Food and Agriculture Research and Technology.

Emilio Magallón has published numerous articles on the Spanish swine sector and has participated in numerous seminars and panel discussions throughout Spain.

He is a member of Anaporc (Spanish Scientific Swine Production Association) and foun-ding member of the AVPA (Association of Swine Veterinary Practitioners of Aragon), and is currently part of its board of directors.

Alberto García FloresAlberto Garcia Flores graduated in Veterinary Medicine from the Faculty of Veterinary Medicine of Zaragoza, Spain, in 2000, with a specialisation in Animal Medicine and Health.

After finishing his studies, he went on to take a specialisation course in swine production. He started his professional career as a veterinary surgeon for the control of infectious diseases associated with production animals.

More than 10 years ago, he joined the swine production company of a multinational firm, where he works as a veterinary surgeon in the areas of production, nutrition, diagnosis and treatment of diseases and carries out tasks related to the technical and economic management of farms. He participates in the planning and carrying out of R&D studies on swine production.

He has published several articles and studies on swine. Furthermore, he has participated in several conferences and panel discussions.

He is a member of the Association of Swine Veterinary Practitioners of Aragon (AVPA).

Roberto Bautista MorenoRoberto Bautista Moreno graduated in Veterinary Medicine from the University of Zarago-za, Spain, in 1990, with a specialisation in Animal Medicine and Health.

He started his professional career in the sheep sector and worked in the areas of sheep health and production in different livestock companies. He later worked as a sales repre-sentative for a pharmaceutical company.

Since 1997 he has been working for livestock production companies, initially in the beef sector as a veterinary surgeon for a company based in the Spanish regions of Aragon and Navarre, and later in the swine sector as a veterinary surgeon for Inga Food, S.A., where he has been in charge of the technical, economic and clinical management of sow farms and fattening units for more than 15 years.

He is a member of the AVPA and is currently a member of its board of directors.

Boris Alonso Sánchez Boris Alonso Sánchez graduated in Veterinary Medicine from the University of Zaragoza, Spain, in 1998, with a specialisation in Animal Production and Agricultural Economics.

In 1999 he started his professional career as a technician and sales representative for several companies. From 2001 to 2007, he was responsible for the management of pig fattening and breeding farms and since 2007 he has been working for the Technical Vete-rinary Service of Inga Food, S.A., in the region of Aragon.

He has participated in numerous seminars and training sessions on swine production.

José Ignacio Cano LatorreJosé Ignacio Cano Latorre graduated in Veterinary Medicine from the University of Zara-goza, Spain, in 1990, with a specialisation in Animal Production and Agricultural Econo-mics. He holds the official certificate in cooperative company management approved by the Spanish Ministry of Labour (1989-1990). In 1991, he took an advanced course on domestic animal nutrition organised by the INRA in Paris, France.

Since 1992 he has been working as a veterinary surgeon for the swine technical service of a company leader in the animal feed industry, and has carried out and implemented arti-ficial insemination on the company’s farms. He specialises in the technical and financial management of breeding, fattening and post-weaning farms. Since 2008, he has served as the team leader of the same company and collaborated with its R&D centre.

José Ignacio has been involved in several national publications and has attended and par-ticipated in numerous seminars and national and international conferences in Spain and in different countries of great relevance in world swine production.


Silvia Almenara DíazSilvia Almenara Díaz graduated in Veterinary Medicine from the University of Zaragoza, Spain, in 2006, with a specialisation in Animal Production and Agricultural Economics.

Her final project towards her Master’s degree in Swine Production and Health, organi-sed in partnership by the faculties of veterinary medicine of the universities of Zaragoza, Barcelona, and by the School of Agriculture Science of Lérida, won a prize awarded by the Association of Swine Veterinary Practitioners of Aragon.

She has done internships in different companies in the sector and since 2008 she has been working for an important animal production company in the area of Zaragoza.

Silvia Almenara has participated in various conferences and training sessions on swine production and health.

Patricia Prieto MartínezPatricia Prieto Martínez graduated in Veterinary Medicine from the University of Zaragoza, Spain, in 2006, with a specialisation in Animal Production and Agricultural Economics.

She completed her training with practical work experience in different areas of production at the schools of veterinary medicine of the universities of Lisbon and Costa Rica. In 2007, she took a Master’s degree in Animal Production and Health organised by the universities of Zaragoza, Lérida and Barcelona.

Patricia Prieto began her career in 2008 at the Technical Veterinary Service of one of the most important companies in the swine sector, where she manages several pig breeding and fattening farms.

She has participated in numerous conferences and training sessions on swine production.

Pablo Magallón VerdePablo Magallón Verde graduated in Veterinary Medicine from the University of Zaragoza, Spain, in 2012.

He has done internships in the swine production company Inga Food, S.A., and has taken courses on Swine Production Medicine Clinical Rotation and Veterinary Diagnostic and Production Animal Medicine at the Iowa State University (USA).

He is currently studying a Master’s degree in Swine Health and Production organised in partnership by the universities of Zaragoza, Lérida, Barcelona and Madrid.

Since 2013 he has been working as a veterinary surgeon in one of the most important livestock companies in Spain.

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Lactation








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Table of contents

1. Introduction

2. Technical and physiological considerations regarding lactation

Natural behaviour of the sow and piglet during lactation

Nursing

Behaviour of the sow in the farrowing room

Weaning

Physiology of lactationMammary gland formation

Anatomical review of the mammary gland

Number and type of teats

Endocrinology of lactation

Lactogenesis

Maintenance of lactation (galactopoiesis)

Milk ejection

Lactation curve and milk production

Phases of nursing

Composition of colostrum

Composition of milk

Physiology of the suckling piglet Mortality at birth-weaning

Hierarchy

Play

Physiology of weaningHormonal changes in the sow

Age at weaning

Weight at weaning and growth curve

Weaning and stress in the piglet

3. Environmental control

Environmental requirements of the lactating sow and piglet

Environmental control systems

Animal welfare requirements

4. Feeding of the lactating sow and piglet

Key concepts of nutritionFeed requirements

Water requirements

Feeding of the lactating sow

Types of feed

Feeding curves

Feeding of the suckling pigletCreep feed

Milk replacers

Yoghurt

Gel

Other dietary supplements

Body condition monitoring systemsVisual monitoring

Body condition scoring

Individual weight control with scales

Control of back fat thickness

Weight control using a measuring tape

5. Lactating sow management

Management practices during lactation

Different management strategies: cross-fostering, nurse sows, artificial lactations, complete lactations

6. Suckling piglet management

Piglet management

Processing of piglets: teeth clipping, tail docking, identification…

Main piglet management proceduresCastration

Inguinal hernia surgery

7. Cross-fostering management

Introduction

Partial cross-fostering

Shunt fostering

8. Weaning management

Sow weaning management

Piglet weaning management

Age at weaning

Types of weaning. Partial weaning

9. Health programmes

Health strategy

Main diseases of the lactating sowMastitis

Digestive problems

Joint problems

Demineralisations

Main diseases of the pigletDiarrhoeic problems

Parasitic problems

Coccidia

Ascaris

Exudative epidermitis

Meningitis

Others

BiosafetyProphylactic programmes

Vaccines for the sow and piglet

Antiparasitic treatments

Systematic treatments

10. Personnel management

Necessary aspects for correct personnel management

Selection

Education

Motivation

Training

Planning

Responsibility

Communication

Staff turnover

Teamwork

Working with objectives

Work health and safety

11. Production targets during lactation

Concept of present sow

Concept of productive sow at first service

Concept of productive sow at first farrowing

Farrowing per sow and year

Weaned piglets per litter

Productivity per sow and yearPresent sow

Productive sow at first service

Productive sow at farrowing

12. Conclusions

13. Reference list

1

2Natural behaviour of the sow and piglet during lactation

NursingImmediately after the birth of her piglets, the sow already has colostrum availa-

ble in her udders, as high oxytocin levels (hormone involved in milk ejection) are

reached after farrowing. From the first day on and progressively, colostrum secre-

tion stops while milk secretion starts; this latter is no longer available continually,

which requires piglets to massage and stimulate the mammary glands to ensure

milk ejection. At the beginning, the frequency of nursing is every 40-60 minutes,

although it decreases as the lactation period progresses.

Short after their birth, piglets compete with each other in order to establish their

social hierarchy. As a result, the largest and more vigorous piglets suckle from the

thoracic teats, which are the most productive. Once the hierarchy is established,

piglets always suckle from same teat. Piglets choose a teat from their second day

of life; they seem to guide themselves through the smell of the saliva they leave

on the teat.

The largest and more vigorous piglets nurse the most productive teats, as a result of the hierarchical order established by competition between the members of the litter.

Technical and physiological considerations regarding lactation

HUSBANDRY AND MANAGEMENT PRACTICES IN FARROWING UNITS II. LACTATION.

2

Behaviour of the sow in the farrowing roomThe behaviour of sows with their piglets has an influence on neonatal mortality

rates, especially as regards the risk of crushing. The sows that remain in lateral

recumbent position allow their piglets better access to their teats. Thus, the sows

that move less and those that do not make sudden movements, prevent many

deaths by crushing from occurring (Fig. 1). Sows with inappropriate behaviour

increase mortality rates.

There is a clear relationship between sows with a good behaviour (good mothers) and productivity.

Figure 1 Sow lying down carefully in order not to crush her piglets.

Figure 2 Piglet crushed by its mother. Skin lesions and cyanosis of the mucosae may be observed.

How dangerous a sow’s movements are depends on how careful she is when lying

down, how fast she does so and where the piglets are. The danger a sow repre-

sents varies according to the environmental conditions and the time of the day.

As a general rule, piglets in danger make strident vocalisations when they are

trapped by the sow. This gives the trapped piglet more chances of survival, as if

the mother takes too long to realise what is occurring and stand up, the piglet will

die by asphyxiation (Fig. 2).


3

Sows need a very quiet environment to nurse their piglets properly and display

appropriate maternal behaviour; any cause of stress (noises, unknown personnel,

etc.) will make them fearful and anxious and may result in difficulties to nurse their

litter and a reduction of their milk production.

The sows that display inappropriate behaviour should be identified so as to con-

trol them and euthanise them if necessary, especially on selection farms. The

selection of sows for numerical productivity should be accompanied by new stu-

dies on behaviour to characterise maternal abilities and thus select those females

with good behaviour.

WeaningUnder natural conditions, weaning is a gradual process in all mammal species.

As the offspring grow, their nutritional needs change and increase. Their mother’s

milk production is therefore insufficient to satisfy them. The offspring progressively

get used to the solid foods required by each species.

In the case of sows, gradually and as lactation progresses, these may even reject

nursing attempts by their piglets. In wild pigs, piglets make a slow transition from

a diet exclusively based on milk to a diet without milk until they become nutri-

tionally independent from the sow at about 8 to 12 weeks of life. Other authors

mention a longer process of up to 17 weeks.

The gradual process through which piglets change from one diet to another inclu-

des four phases.

1. Hiding phase: first week of lactation. Piglets remain isolated in the nest built

by their mother and sporadically make excursions around it.

2. Familiarising phase: second and third week of lactation. Piglets leave the

nest and follow the sow. They remain with the rest of the litter, but do not

interact with the other piglets, or only very little. Piglets start rooting in this

phase.

3. Integration and learning phase: until the seventh week of lactation. Piglets

increase their grazing behaviour and interact with other piglets from their

social group. Sows leave them alone for increasingly longer periods of time,

the time interval between two nursing sessions increases and these latter

are increasingly shorter.

4. Independence phase: until the seventeenth week of lactation, maximum.

Nursing becomes less and less frequent until it stops at a determined

moment. Piglets “function” independently as part of the extended social


4

group. They feed on their own although they still sleep with the social group

together with their mother.

The interval between nursing cycles varies greatly. It lasts 40-60 minutes during

the first week of lactation and then increases to 90 minutes between the second

and fourth week. From the tenth week of lactation, the interval between two nur-

sing sessions lasts 300 minutes.

Physiology of lactation

Mammary gland formationThe formation of the mammary glands from skin cells starts very early during foe-

tal development. Before one month of gestation, it is already possible to observe

the differentiation of the mammary lines, where thickenings occur to eventual-

ly form the future teats, and whose number will be the same as the number of

mammary glands of the adult pig. On about day 70 of foetal life, the future mam-

mary gland can be observed as a bud with an outer part that will form the teat,

and an inner part that will give rise to the mammary ducts. These buds both

develop into the lactiferous ducts and grow in a conical shape, so that they are

raised from the skin surface and form the teat.

On the piglet’s first day of life, there is already a rudimentary duct system with no

gland tissue. Mammary glands remain inactive until puberty. At this moment and

at the start of sexual maturity, they develop under the effect of ovarian hormones,

and the non-glandular tissue starts to develop rapidly. The ducts form a very den-

se network, basically of stroma.

Most of this development takes place from the second half of gestation (70-90

days), when the fat and connective tissue (stroma) is replaced by parenchyma

(lobular-alveolar tissue). From day 90, the number of epithelial cells is highest and

the mammary gland’s secretory activity starts.

After farrowing, the increase in prolactin levels and decrease in oestrogen and

progesterone levels lead to an increase in milk secretion. Sucking by the piglets

and the action of oxytocin lead to the ejection of colostrum and milk.


5

Anatomical review of the mammary glandThe sow’s mammary glands extend from the sternum to the inguinal region. They

appear as raised areas with the shape of half spheres across the ventral region,

each with its respective teat.

As shown in Figure 3, each gland has two totally independent duct systems; each

system has a small cistern and a duct. The cistern or lactiferous sinus is an ellipti-

cal dilation of the duct, whose walls form numerous longitudinal folds, which close

the passage to the lactiferous ducts hermetically. The cistern is communicated

with the gland’s internal wall through the ducts. The function of the ducts is to dra-

in the milk located in the alveoli. Each mammary gland functions independently.

Lactiferous ducts(intra, interlobular and greater)

Teat

Connective tissueLobe

Acini or mammary alveoli

Lactiferous sinus

Figure 3 Structure of the mammary gland. Source: Suis magazine. Anadon et al., 1996.


6

Number and type of teatsThe sow’s number of mammary glands varies depending on the breed; the avera-

ge value is 10 teats for Iberian pig breeds, 10-12 for Duroc-Jersey breeds, 14-16

for Large White and Landrace breeds and 18 or more for Chinese breeds.

Genetic improvement has led to genetic lines of Large White and Landrace sows

with 18 or more teats. The most advanced genetic selection programmes are

currently working on selecting replacement gilts with a minimum of 14-16 functio-

nal teats.

Following the anatomical location of the mammary glands in sows, the first two

pairs are usually thoracic, the last two pairs are inguinal and the other intermediate

pairs are abdominal (Fig. 4). Mammary glands are located on the ventral line (on

the mammary line) and have a certain degree of bilateralism, although it is com-

mon to find a percentage of animals with an odd number of mammary glands.

Anatomical and physiological differences are responsible for variations in milk pro-

duction. The anterior or thoracic mammary glands have a greater blood supply

than the posterior ones (abdominal or inguinal) and therefore produce more milk.

Not all the mammary glands are functional; it is frequent to find inverted or inva-

ginated teats, which characteristically lack a glandular body and are shorter (17-

30 % of sows have one or more inverted teats). These abnormal teats do not

produce milk and their incidence varies according to authors.

Thoracic InguinalAbdominal

Figure 4 Number of mammary glands and anatomical distribution. Source: Barceló and De Paz. Fallo lactacional de la cerda, 2005.


7

Teats and mammary glands according to the sow’s number of gestations or moment of lactation

Figure 5 First-parity gilt.

Figure 7 Ideal teats for nurse sows (long and narrow).

Figure 9 First week of lactation.

Figure 6 Multiparous sow.

Figure 8 Before starting lactation.

Figure 10 Late lactation.


8

Milk production depends on udder massaging and teat sucking by the correspon-

ding piglet. If no piglet suckles from a teat, from the third day without any stimulus

on, the mammary gland will undergo involution, which may become irreversible.

Endocrinology of lactationThe mammary glands experience continuous structural and functional changes

related to the sow’s age (mainly puberty), the cycle phase (follicular or luteal) and

her physiological state: gestation, lactation or weaning.

Every year, the sow’s mammary glands undergo 2.3-2.5 cycles of development,

lactation and mammary involution. Mammary gland development in each lac-

tation has an influence on the glands’ production and functionality in the next

lactation.

The lactation period has two independent phases: lactogenesis or milk formation,

mainly regulated by prolactin; and milk ejection or let-down, regulated essentially

by oxytocin.

LactogenesisIn the gestating sow, progesterone levels start to decrease from the second or

third week before birth, although the reduction is more marked in the last two

days. This decrease in progesterone levels induces an increase in prolactin levels

and therefore, an increase in the size of the mammary glands, which grow mainly

in the last three weeks of gestation and reach their maximum development in the

three or four days previous to farrowing. A discharge of serous fluid through the

teats is observed 48 hours before farrowing and the sow starts to secrete colos-

trum 24 hours before giving birth to her piglets.

Lactogenesis is divided into a secretory phase, during which colostrum and milk

secretion starts, and a second phase of galactopoiesis, during which milk pro-

duction is maintained throughout the whole lactation period until weaning. A good

start of milk production is essential for a good lactation.

Mammary stimulation by a vigorous litter leads to an increase in prolactin levels and enhances milk production.


9

Maintenance of lactation (galactopoiesis)The activity of the pituitary gland is essential for the maintenance of lactation and

for milk secretion to begin. The continued production of prolactin is essential

during the whole lactation period. The sucking stimulus by the piglets keeps pro-

lactin levels high, which prolongs lactation and anoestrus in the sow.

If, for any reason, the sucking stimulus becomes weaker (partial weaning or nurse

sows with very small piglets or piglets that do not nurse enough), the sow may

come into heat even during lactation.

Milk ejectionThe oxytocin released through the hypothalamic-pituitary axis causes milk ejec-

tion or let-down while the piglet is nursing. The production of this hormone is

conditioned by a neurohormonal reflex caused by udder massaging and teat suc-

king by the piglets. The peripheral tactile information at the level of the mammary

glands is transmitted through the nerves to the hypothalamic-pituitary axis, which

induces the release of oxytocin to the bloodstream. The hormone reaches the

mammary glands, where it causes the contraction of the myoepithelial cells and

the emptying of the alveoli. The milk produced passes to the lactiferous ducts and

comes out from the teat to feed the piglets by means of sucking.

Lactation curve and milk productionA sow’s milk production mainly depends on her piglets’ vigour when sucking the

milk from the mammary glands, and varies in function of the litter size, number

of lactations, genetic line and feeding during the gestation phase and above all

during lactation.

The best way to calculate a sow’s milk production is to control the weight of her

piglets, although the data obtained this way may be partly erroneous. According

to the studies of Whittemore and Morgan (1990), it has been established that

every kilogram of weight gained by a piglet is equivalent to four litres of milk.

Therefore, a sow that weans 11 piglets with an average weight of 6.4 kg after

22 days and with a birth weight of 1.4 kg produces 220 litres of milk during her

lactation; that is to say, an average of ten litres a day. In another study (2009),

Collell mentions maximum productions of up to 12 litres a day (Fig. 11).


10

Phases of nursingBased on the piglet’s behaviour, there are three phases during a nursing bout

(Fig. 12).

• First phase: very vigorous previous mammary massage that stimulates

oxytocin production. The piglets compete with each other and scream. The

sow grunts and calls the piglets, which coincides with the elimination of

oxytocin. This phase lasts between 1 and 3 minutes.

• Second phase: known as the milk ingestion or nutritive phase. As they hear

the sow’s signal, the piglets remain quiet and suckle from the teat waiting for

the milk to let down. As soon as it comes out, the piglets drink it very quickly

(Fig. 13). This phase only lasts between 10 and 20 seconds. In this phase,

oxytocin causes the contraction of the myoepithelial cells of the mammary

alveoli and milk let-down occurs.

• Third phase: it includes the massage of the mammary glands after milk

ejection. After ingesting the milk, the piglets massage the mammary glands,

albeit in a less vigorous manner, and the sow becomes quiet and grunts softly.

Three stages may also be distinguished according to who causes the nursing

bout:

• During the first ten days of life of the piglets, in 60-80 % of cases, it is the sow

that stimulates nursing, as she produces more milk than that which piglets are

able to ingest.

Dai

ly p

rodu

ctio

n (k

g)

Weeks of lactation

Lactation curve of a hyperprolific sow

Lactation curve of a sow12

10

8

6

4

2

0

1 2 3 4 5 6 7 8

Figure 11 Lactation curve of a sow.

Editorial Servet, a division of Grupo Asís, has become one of the reference publishing com-panies in the veterinary sector worldwide. More than 15 years of experience in the publis-hing of contents about veterinary medicine guarantees the quality of its work. With a wide national and international distribution, the books in its catalogue are present in many diffe-rent countries and have been translated into nine languages to date: English, French, Por-tuguese, German, Italian, Turkish, Japanese, Russian and Chinese.

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· a production manager in one of the most important spanish swine production companies. for...

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