|
|
|
Figure 1. Production performance with seasonal variation |
| Livestock Research for Rural Development 20 (1) 2008 | Guide for preparation of papers | LRRD News | Citation of this paper |
A survey was carried out in selected organized farms of Darjeeling district of Hilly region, West Bengal to assess the incidence and prevalence of bovine lameness having considerable economical and animal welfare implications between January 2006 to December 2006.
The annual incidence of lameness was 9.42 with the variations in summer and winter was 7.25 and 11.6 respectively. Occurrence of lameness of dairy cattle varied between 3-10 years of age weighing 200-350 kg body weight during 1st- 7th lactation. Production performance varied significantly for all dairy cows in summer months compared with winter months. Concrete rough floor without any bedding materials appeared to promote more cases of lameness with incremental variation of heart rate and respiratory rate irrespective of season.
It was evident that simple descriptive scale (SDS) and visual analogue scale scores (VAS ) methods were negatively correlated with percent lame animals at both seasons.
Key words: Behaviour, Bengal, dairy cattle, India, season, welfare
The importance of lameness in dairy cattle has been interestingly recognized in the last two decades (Kelton et al 1998; Rushen 2001) and is now considered one of the most urgent health and serious welfare problem of dairy cattle as well as one of the most significant economic loses for the dairy industry (Whitaker et al 2000 : Grohn et al 2003) due to reduced milk production (Warnick et al 2001; Green et al 2002), and involuntary culling of lactating dairy cattle (Whitaker et al 2000 and Grohn et al 2003). Pain associated with lameness clearly decreases the welfare of cows (Whay et al 1997, 1998 and O’ Callaghan 2002). Pain likely influences both individual and social behavior of affected animals. For example lame cows have reduced daily activity levels (O’ Callaghan et al 2003), spending more time lying and less time feeding (Galindo and Broom 2002). Moreover, lame cows are less likely to start social interactions with other cows, although they are as likely to be subjected to aggressive behavior by other animals, as sound cows (Galindo and Broom 2002).
The aim of the present study was to describe the incidence and prevalence of lameness in dairy cattle in the hilly area of Darjeeling district of West Bengal over a period of one year as well as to detect gait attributes of lameness in dairy cattle that are due to pain along with etiopathogenesis for development of lameness. It was planned to provide a record as complete as possible of the degree of lameness on the farms and formed part of a wider study of the threat factors implicated in lameness.
The study was carried out on different farms of Darjeeling district. The farms were selected purposively by one veterinary practitioner in each of the regions, who selected the farms without regard for the perceived amount of lameness. The criteria for selection were that the farmers were willing to cooperate for the period of study, to provide records and to allow access to the farms by members of the research team. The study began in December 2005 and data were collected from most of the farms between these one year study periods.
The study included several
parameters:
(1) Prevalence of
lameness in dairy cows in relation to age, calving and lactation, genetics and
conformation, animal behaviour and body weight
(2) Effect of pain on
production performance: average weight of healthy dairy cows for specific
duration was evaluated in comparison with the weight average of lame milking
cows of the same farm for the same duration
(3) Evaluation of pain
assessment using different scoring system as per the methods of Flower and Weary
(2005) (Simple descriptive scale (SDS) score based on response to approach of
the observer, visual analogue scale (VAS) score based on response to a back
stroke, SDS score based on response to a back stroke, heart rate, respiratory
rate and SDS score based on response to handling and palpation of the fore
limbs)
(4) Managerial cause of lameness: housing (type of housing, condition of floor, footbaths and bedding materials), nutritional changes and managemental (maintenance of field and farm track, stockmanship, claw trimming and movement in grazing field and (5) evaluation of biomechanics of joints. Biomechanics of the affected limb in lame cows were measured and compared with the normal population. The flexion and extension of the different joints of affected limbs were measured by goniometers compare with a healthy population. Slide attributes such as stride length, height, duration were also studied following the methods of Flower et al (2005)
Categorical variables were made quantitative by scoring. Mean with standard error for all variables under study and mean comparison results were made by student’s ‘t’ test.
Over the one year of study, the incidence and prevalence of lameness in organized dairy farms of hilly regions of Darjeeling district are given in Table 1.
|
Table 1. Prevalence of lameness in organized dairy farms of hilly region of Darjeeling district |
|||||||||
|
Name of dairy farm |
No. of total animals |
No. of lame animals |
Age of lame animals, years |
weight of lame animals, kg |
Stage of lactation of lame animals |
Genetics and conformation |
Animal behaviour |
||
|
Summer Month |
Winter Month |
Mean standing hours |
Mean lying hours |
||||||
|
Farm A |
20 |
4 |
6 |
6-10 |
250-350 |
4th-7th |
Jersey |
7.5 |
16.5 |
|
Farm B |
200 |
9 |
12 |
6-9 |
200-350 |
4th-5th |
Jersey and Holstein Friesian |
10 |
14 |
|
Farm C |
30 |
3 |
8 |
4-6 |
200-270 |
2nd-4th |
Holstein Friesian cross |
8.8 |
15.2 |
|
Farm D |
12 |
2 |
6 |
5-8 |
220-290 |
3rd-5th |
Jersey cross |
9 |
15
|
|
Farm E |
8 |
1 |
3 |
6 |
250 |
4th |
Jersey cross |
8 |
16 |
|
Farm F |
6 |
1 |
2 |
6 |
240 |
4th) |
Jersey cross |
9 |
15 |
From the table it has been observed that incidence and prevalence of lameness vary greatly in herds within the agroclimatic zones. The age group of animals for developing lameness varies between 4-10 years with an average body weight of 200-350 kg ranging from 2nd -7th lactation. In addition to geographical variability, seasonal differences in incidence and prevalence of lameness in summer and in winter were also evident. The average time spent lying down was significantly more than standing in the majority of the observations (Table 1). Lying down is considered an important aspect of behaviour in dairy cows (Wierenga and Hopster 1990). Dairy animals should lie down for about 9-12 hours daily (Suss and Andreay 1984) in the present study the average period spent lying down during the two periods of observations was 15.28 hours which may have been due to fewer disturbances (Singh et al 1994), suggesting that they needed to alleviate pain and were in some discomfort. The incidence and prevalence of lameness among adult dairy cattle derived from the study provide a basis for the epidemiology of lameness in the hill region of West Bengal. In other studies the estimates of incidence of lameness in Great Britain ranged from 5.5 to 65% (Whitaker et al 2000; Ward 1994; Murray et al 1996). However, similar to that reported by Clarkson et al (1996), there was an uneven distribution between winter and summer (mean ± SE, 30.6 ± 5.92, 13.4 ± 2.28 respectively) in this study. The major reason for the apparent reduction in the incidence of lameness in summer is probably that fewer visits were paid to the farms; as a result, the enthusiasm of some farmers waned. Besides, seasonal differences in incidence and prevalence may be due to differences in management of cattle during winter and summer (Murray et al 1996; Whitaker et al 2000).
In the present study, production performance varied significantly for all lame dairy cows irrespective of seasonal variation (Figure 1).
|
|
|
Figure 1. Production performance with seasonal variation |
Milk production in lame cows may be affected due to perception of pain and subsequent anorexia. Another explanation might be that the lame cows appeared significantly more restless while being milked than the normal cows, presumably because they were in some discomfort (Hassall et al 1993).
Majority of lame dairy cattle were kept in housing with concrete base and some were of earthen floor. The concrete floor appeared to slope from front to back. We observed that concrete rough based floor being abrasive with moisture due to accumulation of excreta favoured development of lameness. No bedding materials either in the form of saw dust or chopped straw and/ or long straw were provided in floor of any farm. It was also been observed that there was no provision of foot bathing in the majority of the farms (Table 2).
|
Table 2. Managemental aspect in organized dairy farms in the hilly region of Darjeeling district |
|||||||||||
|
Name of dairy farm |
Type of housing |
Condition of floor |
Foot bath |
Bedding material |
|||||||
|
Pacca |
Kachcha |
Loose |
Tie up stall |
Concrete Smooth |
Abrasive with moisture |
Rough |
Given |
Not given |
Given |
Not |
|
|
Farm A |
√ |
|
|
√ |
√ |
√ |
√ |
|
√ |
|
√ |
|
Farm B |
√ |
|
|
|
|
√ |
√ |
|
√ |
|
√ |
|
Farm C |
√ |
|
|
|
|
√ |
√ |
|
√ |
|
√ |
|
Farm D |
√ |
|
|
|
|
√ |
√ |
|
√ |
|
√ |
|
Farm E |
√ |
|
|
|
√ |
|
|
|
√ |
|
√ |
|
Farm F |
√ |
|
|
|
|
√ |
√ |
√ |
|
|
√ |
Many studies have reported an association between housing and lameness (Arkins 1981; Baggott and Russell 1981). Housing on concrete has a more deleterious effect on claw health than housing on soft surfaces such as straw (Bazeley and Pinsent 1984). Bedding may play an important role in the prevention of claw lesions; it keeps the feet dry which has a positive effect on claw health (Brochart 1987). He found a higher incidence of lameness in cattle on concrete. An abrasive surface along with moisture predisposes cattle to sole lesions (Murphy and Hannan 1986). In the present study we observed that lameness developed due to keeping the animals on concrete hard floor with moisture containing abrasive surface. Besides, lack of bedding appears to play a vital role to influence lameness. Foot baths are advocated for their disinfectant and astringent action (Baggott and Russell 1981). In the present study it was not a general practice on the majority of farms. Although, considering the multiplicity of factors involved, foot baths alone may not be able to prevent lameness in a herd (Sumner and Davis 1984).
It was observed from the findings in relation to nutritional status of organized dairy farms in hilly region of Darjeeling district (Table 3) that all the dairy animals reared under study area have been offered carbohydrate and concentrate without high dietary protein, balanced diet and mouldy feed.
|
Table 3. Nutritional status in organized dairy farms of hilly region of Darjeeling district |
||||||||||||||||
|
Name of dairy farm |
Carbohydrate in large meals |
High dietary protein |
Balanced diet |
Mouldy feed |
Concentrate |
Roughage |
Feeding before calving |
Sudden change in ration |
||||||||
|
Yes |
No |
Yes |
No |
Yes |
No |
Yes |
No |
Green fodder |
Fodder and straw |
straw |
Yes |
No |
Yes |
No |
||
|
Farm A |
√ |
|
|
√ |
|
√ |
|
√ |
√ |
√ |
|
|
|
√ |
|
√ |
|
Farm B |
√ |
|
|
√ |
|
√ |
|
√ |
√ |
|
√ |
|
|
√ |
|
√ |
|
FarmC |
√ |
|
|
√ |
|
√ |
|
√ |
√ |
√ |
|
|
|
√ |
|
√ |
|
FarmD |
√ |
|
|
√ |
|
√ |
|
√ |
√ |
√ |
|
|
|
√ |
|
√ |
|
Farm E |
√ |
|
|
√ |
|
√ |
|
√ |
√ |
√ |
|
|
|
√ |
|
√ |
|
Farm F |
√ |
|
|
√ |
|
√ |
|
√ |
√ |
√ |
|
|
|
√ |
|
√ |
The table demonstrates that all the animals of the farms (except one farm) were provided with sufficient green fodder and roughage and another one farm was provided with only fodder and straw. Not a single farm was provided with only straw as roughage for the dairy animals. Further, it was revealed that there was no sudden change in the ration for the dairy animals under study. Nutrition is considered to be an important factor involved in the initiation of laminitis (Nocek 1997). Increased feeding of fermentable carbohydrates has been implicated as a cause of laminitis in cattle (Nocek 1997; Thoefner et al 2004). In a series of studies a higher concentrates forage ratio (Manson and Leaver 1989), a higher total concentrate amount (Manson and Leaver 1988; Livesay et al 1998) all resulted in a higher lameness score than in control cows fed less intensive diets.
All the organized dairy farms under study in the hilly region had brick soiling for farm track excepting one farm which had muddy soil. Hoof examination and claw trimming of dairy animals were not routinely carried out in all the organized farms under study. Further it was found that all the animals on organized dairy farms in hilly regions were stall feed (Table 4).
|
Table 4. Managerial factors in organized dairy farms of hilly region of Darjeeling district |
|||||||
|
Name of dairy farm |
Field and maintenance of farm track |
Stockman ship (Hoof examination) |
Claw trimming |
||||
|
Brick soiling |
Hard soil |
Muddy soil |
Yes |
No |
Yes |
No |
|
|
Farm A |
√ |
|
|
√ |
|
|
√ |
|
Farm B |
|
|
√ |
|
√ |
|
√ |
|
Farm C |
√ |
|
|
|
√ |
|
√ |
|
Farm D |
√ |
|
|
|
√ |
|
√ |
|
Farm E |
√ |
|
|
|
√ |
|
√ |
|
Farm F |
√ |
|
|
|
√ |
|
√ |
Proper maintenance of farm tracks and stockman’s practice play an important role in reducing the incidence of lameness (Chesterton 1989; Fraser and Broom 1990). Regular claw trimming especially before calving has been found to reduce lameness associated with laminitis when correctly performed (Manson and Leaver 1988). In the present study maintenance of farm tracks did not play vital role in lameness as mostly the animals were stall fed. Although, regular hoof examination and claw trimming were not carried out during the study which may be a contributory factor for lameness.
Angle of flexion and extension of affected joints and gait of the lame animals revealed that lame dairy cows had minimum angulations of the affected joints in comparison to healthy dairy cattle and strides of sound cows were faster, longer and shorter duration than the strides of lame cows (Table 5, Figure 2-4).
|
Table 5. Findings of biomechanical studies in different seasons |
||||
|
Category |
Summer month |
Winter month |
||
|
Healthy cows |
Lame cows |
Healthy cows |
Lame cows |
|
|
Stride length (cm) (Mean ±SE) |
137±0.21 |
128± 0.34 |
132±0.33 |
122± 0.42 |
|
Stride height (cm) (Mean ±SE) |
9.31± 0.20 |
8.32± 0.22 |
8.75± 0.34 |
7.26±0.33 |
|
Stride duration (seconds) (Mean ±SE) |
1.44± 0.03 |
1.63± 0.02 |
1.36± 0.03 |
1.80± 0.01 |
|
|
|
Figure 2. Bar showing the findings of stride length in different seasons |
|
|
|
Figure 3. Bar showing the findings of stride height in different seasons |
|
|
|
Figure 4. Bar showing the findings of stride duration in different seasons |
Quantitative variable like percent of lame animals at summer and winter, animal behavior both in standing and lying conditions, Simple descriptive scale (SDS) score, postures, vocalization, visual analogue scale (VAS) score, activity at rest and eating and mental status were compared and found that except activity at rest all other quantitative values have shown no significant difference. It was evident that SDS and VAS scores methods were negatively correlated with percent lame animals at both seasons (Table 6, 7 and 8).
|
Table 6. Pain perception and other responses by lame cows in organized dairy farms of hilly region of Darjeeling district |
|||||||||
|
Name of dairy farm |
SDS Score |
SDS Score by F and W, 05 |
SDS Score (Backstroke) |
SDS Score (Fore limb palpation) |
Activity |
Posture |
Vocalization |
||
|
Rest |
Eating |
Guarding |
Recumbency |
||||||
|
Farm A |
4 |
2.6 |
4 |
4 |
0 |
0 |
|
0 |
0 |
|
Farm B |
2.64 |
2.27 |
1.91 |
3 |
0 |
0 |
1.27 |
0.6 |
0 |
|
Farm C |
2.54 |
2.13 |
2 |
2 |
0 |
0 |
1.37 |
0.5 |
0 |
|
Farm D |
3 |
2 |
2.2 |
1 |
0 |
2 |
1 |
0.8 |
0 |
|
Farm E |
1.86 |
1.9 |
3 |
2 |
0 |
0 |
1.2 |
0 |
0 |
|
Farm F |
2.34 |
2 |
2 |
2.2 |
1 |
2 |
1 |
0 |
2.2 |
|
Table 7. VAS-score by lame cows in organized dairy farms of hilly region of Darjeeling district |
||
|
Name of dairy farm |
VAS-score |
|
|
Summer month |
Winter month |
|
|
Farm A |
61.2 |
65.4 |
|
Farm B |
65.1 |
72.1 |
|
Farm C |
58.5 |
62.2 |
|
Farm D |
41.8 |
45.6 |
|
Farm E |
65.1 |
70.6 |
|
Farm F |
41.8 |
48.6 |
|
Table 8. Mean with Standard Error for all variables under study |
||
|
FARM |
Mean |
SE |
|
Lame animal (Summer) |
13.4 |
2.28 |
|
Lame animal (Winter) |
30.6 |
5.92 |
|
Lame animal summer (angular transformed) |
21.0 |
|
|
Lame animal Winter (angular transformed) |
32.8 |
|
|
Animal behavior (Standing) |
8.72 |
0.36 |
|
Animal behavior (lying) |
15.3 |
0.36 |
|
Housing type |
1.17 |
0.17 |
|
Floor condition |
2.33 |
0.42 |
|
Foot bath |
0.17 |
0.17 |
|
High protein diet |
1.00 |
0.00 |
|
Balance diet |
0.00 |
0.00 |
|
Roughages |
1.17 |
0.17 |
|
Feeding before calving |
0.00 |
0.00 |
|
Farm track condition |
0.83 |
0.17 |
|
Stockmanship |
0.17 |
0.17 |
|
Claw trimming |
0.00 |
0.00 |
|
SDS |
2.73 |
0.30 |
|
SDS (F & W method) |
2.15 |
0.10 |
|
SDS back stroke |
2.52 |
0.34 |
|
SDS fore limb palpation |
2.37 |
0.42 |
|
Posture (Guarding) |
1.14 |
0.07 |
|
Posture recumbency |
0.32 |
0.15 |
|
Vocalization |
0.37 |
0.37 |
|
Activity (Rest) |
0.17 |
0.17 |
|
Activity (Eating) |
0.67 |
0.42 |
|
VAS(Summer) |
55.6 |
4.49 |
|
VAS (Winter) |
60.7 |
4.58 |
Many tools exist to assess pain in human beings, and a few have been used in veterinary medicine. None are perfect, primarily because of the subjective and unmeasurable nature of pain even in people (Hamill-Ruth and Marohn 1999) and especially in veterinary patients because they can not communicate verbally. Currently, there does not seem to be suitable “tool” accurately. However, in the present study an attempt has been made to evaluate the pain perception in lame cows following method of Flower and Weary (2005). In lame cows, the pain not only originates from the actual site of the lesion located in the digit but also the tissues surrounding it which may become sensitized, making the use of part or all of the affected claw or foot uncomfortable for walking. When the central nervous system is sensitized by stimuli originating from digital lesion, the whole body becomes hypersensitive to a variety of stimuli which may accentuate the pain response. Therefore, lame cows experiencing pain in an affected foot may encounter other traumatic stimuli such as being pushed or barged by other cows, excessive goading by the stockman, walking on uneven sharp or slippery surfaces, all of which may produce an exaggerated pain response (Whay 1997); this behavior in lame cows may also occur in presence of non-traumatic stimuli such as milking or maneuvering in and out of cubicles. In the present study similar results were also found in lame dairy cows compared with healthy animals. Incremental variation of heart rate and respiratory rate was observed in lame cows compared to healthy dairy cattle irrespective of season (Table 9, Figure 5 and 6).
|
Table 9. Findings of physiological studies in different seasons |
||||
|
Category |
Summer month |
Winter month |
||
|
Healthy cows |
Lame cows |
Healthy cows |
Lame cows |
|
|
Respiratory rate (/minute) (Mean ±SE) |
20.4±0.02 |
27.4± 0.03 |
16.0±0.01 |
24.2± 0.02 |
|
Heart rate (/minute) (Mean ±SE) |
50.5± 0..02 |
64.3± 0.04 |
58.6± 0.01 |
69.8±0.02 |
|
|
|
Figure 5. Bar showing the findings of respiratory rate in different seasons |
|
|
|
Figure 6. Bar showing the findings of heart rate in different seasons |
The age group of animals between 3-10 years is more susceptible for developing lameness. Simultaneously, the average body weight of 200-350 kg can also trigger lameness. Therefore, attention has to be taken during this age group and body weight of animals.
Prolonged lying condition of animals, concrete based pucca housing, feeding of only green fodder have to be avoided to make free animals from lameness. On the other hand, claw trimming, hoof examination, feeding before calving and regular Stockmanship are very much important to avoid lameness of animals.
The excessive summer and winter may be the predominant factors for
developing lameness of animals for which one should take proper care.
The authors are thankful to Dr. Lalkrishna, Assistant Director General, Indian Council of Agricultural Research for giving necessary permission to publish the data from ICAR ad-hoc project.
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Received 5 October 2007; Accepted 12 October 2007; Published 1 January 2008
