Printer Friendly

Effect of sub-clinical mastitis on milk yield and composition of dairy goats in Tanzania.

INTRODUCTION

Mastitis mastitis (măstī`tĭs), inflammation of the breast. Mastitis most commonly occurs in nursing mothers between the first and third weeks after childbirth, usually of the first child.  is universally recognised as one of the most costly disease in the dairy industry [1]. The major components of the economic losses caused by mastitis are: reduced milk yield, veterinary charges, increased labour costs, discarded milk and reduced longevity of milking goats [2]. High mortalities of kids born to goats with mastitis make the disease economically significant to the goat industry [3]. Milk yield in dairy animals can be reduced by as much as 25% and at times up to 100% [4]. The monetary loss the farmer gets as a result of this disease due to cows not producing optimally was estimated in Tanzania to be about Tsh. 52,800.00 (about US $42) per cow per year, which was quite high [5].

Reports on the effect of bovine mastitis on milk composition show consistently lower lactose and higher chloride contents in quarters with mastitis than in those without mastitis [5,6]. Changes in fat content as a result of mastitis vary between sample populations mainly because the variation largely depends on the severity of mastitis and the magnitude of reduction in milk yield. The effect of mastitis on crude protein content of milk is not very clear under sub-clinical conditions although it is well known that at advanced stages, the trend is an increase in crude protein [7].

The majority of studies on the influence of mastitis on milk composition have been conducted in dairy cattle. In Tanzania there is a rapid increase of dairy goats especially among resource poor smallholder Noun 1. smallholder - a person owning or renting a smallholding
Britain, Great Britain, U.K., UK, United Kingdom, United Kingdom of Great Britain and Northern Ireland - a monarchy in northwestern Europe occupying most of the British Isles; divided into England and
 farmers. These goats contribute substantially towards sustainable supply of milk for children and women. Family incomes and nutrition have appreciably improved in the areas where dairy goats have been introduced [8]. However, an earlier study in two locations of Tanzania has clearly shown a high prevalence of subclinical subclinical /sub·clin·i·cal/ (sub-klin´i-k'l) without clinical manifestations.

sub·clin·i·cal
adj.
Not manifesting characteristic clinical symptoms. Used of a disease or condition.
 mastitis in goats of over 70% [8]. Such a high incidence calls for the need to evaluate the effect of this disease on the yield and composition of milk. This is of paramount importance because there is limited information in goats on the effect of clinical and sub-clinical mastitis on milk yield and composition [4]. The objective of this study was therefore to establish the effect of sub-clinical mastitis on milk yield and composition in dairy goats.

MATERIALS AND METHODS

Study area and animals

This study was carried out at Magadu dairy farm. The farm belongs to the Department of Animal Science and Production of the Sokoine University of Agriculture (SUA), Morogoro, Tanzania. SUA is situated about 2.5 km south of Morogoro municipality at an altitude of 550 m above sea level and gets an average annual rainfall of approximately 880 mm. For most parts of the year temperatures vary between 27[degrees] and 31[degrees]C.

The goats at Magadu dairy farm were first crosses ([F.sub.1]; Norwegian landrace Landrace

a large white pig with ears pitched forwards and top edge level with topline of snout. There are many ethnic varieties. Originated in Denmark.
 x Local Tanzanian goats) with 50% Norwegian blood.

Milk yield and screening for mastitis

Records on kidding date and parity for individual animals were taken. All lactating animals were screened and scored for mastitis using the California Mastitis Test California mastitis test

an indirect test for bovine mastitis based on the presence of a high leukocyte count in mastitic milk. The test can be used in the milking shed or in the laboratory and as a test for individual quarters, or cows, or as a herd test.
 (CMT CMT Certified Medical Transcriptionist.

CMT
abbr.
Certified Medical Transcriptionist



CMT

California mastitis test.
) as described by Schalm and Noorlander [9]. Following screening, the CMT score of each udder quarter was included in the individual animal records. Goats were screened twice at two months interval.

All quarters screened for mastitis were milked to completion immediately following screening and in the next milking. The does were milked twice per day at around 6am and 5pm and the volume of milk obtained in each instance was measured in ml.

Collection of milk samples

About 80 ml of milk were collected from each of the screened quarter for milk composition analysis. Milk samples were preserved with potassium dichromate potassium dichromate
n.
A bright yellowish-red crystalline compound, K2Cr2O7, used as an oxidizing agent, and in pyrotechnics, explosives, and safety matches.

Noun 1.
 [10]. Before analyses composite samples were obtained by mixing quarter morning and evening samples in proportion to the milk yield at each milking.

Analyses for milk constituents

Milk samples from each quarter were analysed for crude protein (CP), butterfat butterfat

globules in the milk of all species. It can be separated to make butter. The nutritional value and the price of milk are judged on, among other things, the butterfat content of the milk.
 (BF), lactose and chloride percentages. Total protein was determined by the standard Kjeldahl method for nitrogen analysis [11]. Nitrogen content was multiplied by 6.38 to obtain the CP percentage. The BF content was determined by the standard Gerber method [12]. The lactose content was determined according to the method described by IDF (Intermediate Distribution Frame) A wiring rack located between the MDF (main distribution frame) and the intended end user devices (telephones, routers, PCs, etc.). Cables run from the outside world to the MDF and then to the IDFs. See MDF and wiring rack.  Standard No.28 [13]. The chloride content of the milk samples was determined by titration titration (tītrā`shən), gradual addition of an acidic solution to a basic solution or vice versa (see acids and bases); titrations are used to determine the concentration of acids or bases in solution.  using silver nitrate silver nitrate (nī`trāt), chemical compound, AgNO3, a colorless crystalline material that is very soluble in water. The most important compound of silver, it is used in the preparation of silver salts for photography, in chemical  solution [14]. Koestler values usually increase in cases of mastitis, thus indicating infection. For normal milk this value is around 2.3. Koestler values (in percent) were computed by dividing the chloride content by lactose percentage for all CMT scores.

Statistical analysis

Records were analysed for effects of CMT score, parity, stage of lactation lactation

Production of milk by female mammals after giving birth. The milk is discharged by the mammary glands in the breasts. Hormones triggered by delivery of the placenta and by nursing stimulate milk production.
, quarter, sampling occasion (sampled twice) and milking time (for milk yield only). There were four (4) parities (1st, 2nd, 3rd and 4th and above) and three stages of lactation (1 = [less than or equal to]5 months of lactation, 2 = >5 and <8 months and 3 = [greater than or equal to]8 months).

Analyses were performed according to the General Linear Models (GLM GLM Global Language Monitor
GLM Global Marine (stock symbol)
GLM Graduated Length Method (ski instruction)
GLM Good Looking Mom (used in pediatric practices)
GLM God Loves Me
) procedures of SAS (1) (SAS Institute Inc., Cary, NC, www.sas.com) A software company that specializes in data warehousing and decision support software based on the SAS System. Founded in 1976, SAS is one of the world's largest privately held software companies. See SAS System.  [15].

The model used was:

[Y.sub.ijklmno] = [mu] [] [] + [L.sub.i] + [T.sub.j] + [B.sub.k] + [S.sub.l] + [Q.sub.m] + [A.sub.n] + b([X.sub.ijklmno]-x) + [E.sub.ijklmno]

Where:

[Y.sub.ijklmno] = dependent variable: milk yield, CP, BF, lactose, and Chloride

[mu] = General mean

[L.sub.i] = Effect of the ith sampling occasion (i = 1,2)

[T.sub.j] = Effect of sub-clinical mastitis (CMT score) (j = 0, 1, 2, 3, 4)

[B.sub.k] = Effect of age in parturition parturition
 or birth or childbirth or labour or delivery

Process of bringing forth a child from the uterus, ending pregnancy. It has three stages.
 number (k =1, 2, 3, 4)

[S.sub.l] = Effect of the lth stage of lactation (l = 1, 2, 3)

[Q.sub.m] = Effect of the mth quarter (1 = right, 2 = left)

[A.sub.n] = Effect of the nth milking time (1= morning, 2 = evening)

b = Regression coefficient Regression coefficient

Term yielded by regression analysis that indicates the sensitivity of the dependent variable to a particular independent variable. See: Parameter.


regression coefficient 
 

[X.sub.ijklmno] = Milk yield of the individual doe on the sampling day

x = Mean milk yield

[E.sub.ijklmno] = Random error term

The regression (covariate) was not included in the model when analysing milk yield data and effect of milking time was not fitted in the model when analysing milk components because morning and afternoon samples were mixed proportionately.

RESULTS

Milk yield

Least squares means of quarter milk yield per milking for the various factors are presented in Table 1. The overall mean quarter milk yield was 136.4 [+ or -] 3.9 ml. Sub- clinical mastitis had a significant negative effect on quarter milk yield (P<0.001). There was an apparent decrease in milk yield with increase in CMT score. Effect of stage of lactation on milk yield was also significant (P<0.001). The effects of milking time and sampling occasion were highly significant (P<0.001) sources of variation. Morning milk yield was 40.4% higher than afternoon milk.

Milk Composition

The overall mean quarter CP percentage was 4.02 [+ or -] 0.08(Table 1). Mastitis had a significant (P<0.01) effect on quarter CP percentage while parity and stage of lactation had no significant effect on levels of protein content. Quarters with highest CMT score had highest CP content.

The mean quarter BF percentage was 5.32 [+ or -] 0.13(Table 2). There was a significant (P<0.01) reduction in BF content with increasing CMT score. Other factors that significantly influenced BF content were sampling occasion (P<0.001), stage of lactation (P<0.05) and milk yield (P<0.001). Butterfat increased from first (4.30%) to second occasion (6.35%) of sampling and also increased with stage of lactation from 4.59% in first stage to 6.16% in the last stage. Further, BF content in quarters with mastitis was lower compared to those with negative CMT score.

The overall mean quarter lactose percentage was 3.83 [+ or -] 0.08. The least square means of quarter lactose percent in relation to the various factors are shown in Table 2. None of the factors studied had a significant effect on quarter lactose percentage although lactose content tended to decrease with increase in CMT score.

Table 3 presents the least squares means for quarter chloride percentage for the various factors under study. The overall mean quarter chloride percentage was 0.244 [+ or -] 0.003. The effect of mastitis on quarter chloride percentage was highly significant (P<0.001) with a tendency for chloride content in milk to increase with increase in CMT score. Other significant effects on chloride percent included parity (P<0.001), sampling occasion (P<0.001) and udder quarter (P<0.05).

A very high Koestler value of 6.4% was obtained when it was computed using overall mean percentages of chloride and lactose. Koestler values for negative, trace, +1, +2 and +3 CMT scores were 5.3, 5.7, 6.7, 5.7 and 8.1, respectively showing an increase in values with severity of mastitis.

DISCUSSION

Milk yield

Sub-clinical mastitis had a significant negative effect on quarter milk yield. Such findings concur with previous reports in dairy goats [16] and in dairy cows [5,6], which showed significantly lower milk yield in mastitic mastitic

emanating from or pertaining to mastitis.
 quarters than in non-mastitic quarters. Mastitis is associated with tissue damage that brings about lowered milk yield or cessation of milk synthesis. The mechanism inhibiting the milk synthetic activity has been discussed in detail by a number of workers [2, 17].

Milk composition

The significant increase in CP content observed at Magadu has also been reported in severe bovine mastitis [7]. With severe inflammation, the combined effects of increased seepage of blood derived proteins and increased concentration of protein due to lowered milk yield may result in increased level of protein. In cases where CP content does not change, studies have shown that casein casein (kā`sēn), well-defined group of proteins found in milk, constituting about 80% of the proteins in cow's milk, but only 40% in human milk.  is dramatically reduced while the level of non-casein protein increases resulting in no change of CP [7]. Contrasting results have been reported by those working with bovine mastitis who found no significant change in CP with severity of mastitis [5, 6].

In this study mastitis significantly affected BF percentage but conflicting results have been reported on the effect of bovine mastitis on BF content. While some authors have demonstrated a reduction in BF, others have shown BF percentage to increase with severity of mastitis [5, 7, 18, 19]. Severity of mastitis seems to determine the magnitude of the effect. In mild cases of mastitis, milk yield is reduced without concomitant reduction in BF percentage. However, with severe inflammation both milk yield and BF concentration are significantly reduced.

There was a general tendency for lactose to decrease with increasing CMT score though this milk component was not significantly affected by sub-clinical mastitis. Studies with bovine mastitis have shown dramatic reduction in lactose content with severity of mastitis [5, 6]. Goats are reported to be less susceptible to mastitis and that partly explains the lesser effect of sub-clinical mastitis on milk lactose content observed in this study [2]. It is further speculated that the level of mastitis as indicated by CMT score did not reach a stage of causing significant reduction in lactose percentage. Further studies with clinical mastitis are, therefore, needed in order to establish its influence on lactose content in goat milk.

The significant increase in chloride percent with severity of mastitis concurs with earlier reports [5, 6]. The increase in chloride percent with mastitis is due to the increased permeability of blood vessels, which allows seepage of plasma into the udder. Even a small amount of blood derived exudates in milk is reported to result into an elevation in amount of chloride [20].

The overall percent chloride of 0.244% was higher than results observed in the literature where chloride percentages of a range of 0.107 to 0.193% have been reported [21, 22]. The high mean would suggest existence of mastitis in the flock that was studied as was reported earlier [8].

In mastitis cases, as lactose decreases it is compensated for by increase in chlorides in order to maintain osmotic pressure osmotic pressure
n.
The pressure exerted by the flow of water through a semipermeable membrane separating two solutions with different concentrations of solute.
. However, the Koestler values obtained in this study are much higher compared to that shown by other reviews of about 2.3% [23]. The main reason for high Koestler values here is that the chloride content in milk was almost double the expected values as discussed above.

CONCLUSION AND RECOMMENDATION

Conclusion

1. It has been shown that sub-clinical mastitis can reduce milk yield up to 29.4%.

2. There was a tendency for CP and chloride percentages to increase with severity of mastitis, however, the chloride values obtained in this study were higher than expected.

3. Mastitis significantly reduced BF content of milk. Further, sub-clinical mastitis had no significant influence on lactose content though there was a tendency for this component to decrease with increase in CMT score.

Recommendation

It is recommended that further studies involving a larger sample of does and those with clinical mastitis be conducted to substantiate the present findings and economic losses resulting from mastitis in goats be assessed.

ACKNOWLEDGEMENT

Financial support from the Norwegian Agency for International Development (NORAD NORAD
abbr.
North American Aerospace (formerly Air) Defense Command
) is gratefully acknowledged.

REFERENCES

[1.] Alrawi AA, Pollak EJ and RC Laben Genetic analysis of California mastitis test records. I. Coded tests. J. Dairy Sci. 1979; 62: 1115-1124.

[2.] Blood DC and OM Radostits Veterinary Medicine veterinary medicine, diagnosis and treatment of diseases of animals. An early interest in animal diseases is found in ancient Greek writings on medicine. Veterinary medicine began to achieve the stature of a science with the organization of the first school in the : A textbook of diseases of cattle, sheep, pigs, goats and horses. Bailliere Tindall, Philadelphia. 1989:501-559.

[3.] Addo PB, Chimene CN and FIA FIA

feline infectious anemia.
 Eid Incidence and importance of Chronic mastitis in Nigeria goats. Bull. Anim. Hlth and Prod. Africa 1980; 28: 225-231.

[4.] Peacock C Improving Goat Production in the Tropics. Manual for development workers. Oxfam U.K and Ireland in association with FARM--Africa. 1996: 200202.

[5.] Mosha CJS CJS®

The abbreviation for Corpus Juris Secundum, which is a comprehensive encyclopedia of the principles of American law.

Corpus Juris Secundum (CJS) serves as an important research tool that enables a user to locate statements and reported decisions on
 Effects of Mastitis on yield and composition of milk in selected dairy farms in Morogoro Municipality. Unpublished M.Sc. Dissertation, Sokoine University of Agriculture (SUA), 1993.

[6.] Nangwala SW Effect of mastitis on quarter milk yield response to improved feeding. Unpublished M. Sc. Dissertation, Sokoine University of Agriculture, 1996.

[7.] Ashworth US, Forster TL and LO Luedecke Relationship between California mastitis test reaction and composition of milk from opposite quarters. J. Dairy Sci. 1967; 50:1078-1082.

[8.] Moshi NG, Kifaro GC and UM Minga Prevalence of mastitis in dairy goats on some selected farms in Morogoro and Arusha, Tanzania J. Agric. Sci. 1998;1(2): 173-180.

[9.] Schalm OW and DO Noorlander Experiments and observations leading to the development of the California Mastitis Test. J. American Vet. Medical Assoc. 1957; 130: 199-204.

[10.] Weaver HC and M Kroger Protein, casein and non-casein protein percentages in milk with high somatic cell somatic cell
n.
Any cell of a plant or an animal other than a germ cell.
 counts. J. Dairy Sci. 1977; 60: 878-881.

[11.] AOAC. Association of Official Analytical Chemists. Official Methods of Analysis 15th Edition Arlington Virginia, USA, 1990.

[12.] Van den Berg Van den Berg is the surname of:
  • Rudolf van den Berg (born 1949), Dutch director
  • Albert van den Berg (born 1976), South African rugby player
  • Jan Hendrik van den Berg (born 1914), Dutch psychologist
  • Janwillem van den Berg (1920-1985), Dutch speech scientist
 JCT JCT Junction
JCT Jerusalem College of Technology
JCT Joint Contracts Tribunal (UK build contracts governing body)
JCT Journal of Coatings Technology
JCT John Christner Trucking
JCT Journal of Curriculum Theorizing
 Dairy Technology in the tropics and sub-tropics. Centre for Agricultural Publishing and Documentation (Pudoc) Wageningen, 1988.

[13.] IDF. (International Dairy Federation) Determination of the lactose content of milk. IDF International Standards No. 28, 1974.

[14.] Marth EH Standard Methods for the Examination of Dairy Products. Donely and sons Inc. Crawfordsville, USA, 1978.

[15.] SAS. The GLM procedure. SAS/STAT User's guide. 6.03 edition, SAS Institute Incorporation. Cary, NC, 2002.

[16.] Dulin A, Paape M, Schultze W and B Weinland Effect of parity, stage of lactation and intramammary infection on concentration of somatic cells and cytoplasmic cytoplasmic

pertaining to or included in cytoplasm.


cytoplasmic inclusions
include secretory inclusions (enzymes, acids, proteins, mucosubstances), nutritive inclusions (glycogen, lipids), pigment granules (melanin, lipofuscin,
 particles in goat's milk. J. Dairy Sci. 1983; 66: 2426-2433.

[17.] Jubb KVF KVF Killing Vector Fields  and PC Kennedy: Pathology of domestic animals. Vol. 1. Academic Press, New York New York, state, United States
New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of
, 1970:552-572.

[18.] Janzen JJ Economic losses resulting from mastitis. J. Dairy Sci. 1970; 53(8): 1151-1161.

[19.] Philpot WN Influence of sub-clinical mastitis on milk production and milk composition. J. Dairy Sci. 1967; 50: 978-985.

[20.] Coles EN Veterinary Clinical Pathology clinical pathology
n.
1. The practice of pathology as it pertains to the care of patients.

2. The subspecialty in pathology concerned with the theoretical and technical aspects of laboratory technology that pertain to the
. W.B. Saunders Company, 1986:359-367.

[21.] Parkash S and R Jenness The composition and characteristics of goat milk: A review. Dairy Sci. Abstr. 1968; 20: 67-87.

[22.] Payne WJA WJA Women's Jewelry Association
WJA Web JetAdmin (HP software)
WJA Water Jetting Association (UK)
WJA Web Jet-Admin
 [A.sub.n] Introduction to Animal Husbandry animal husbandry, aspect of agriculture concerned with the care and breeding of domestic animals such as cattle, goats, sheep, hogs, and horses. Domestication of wild animal species was a crucial achievement in the prehistoric transition of human civilization from  in the Tropics. Longman John Wiley and Son, Inc., New York, 1990.

[23.] Kurwijila RL Genetic and environmental aspects of milk production under tropical environment. Compendium for M.Sc. Course in Dairy production and management. Mimeograph, Morogoro, 1991.

Kifaro GC (1) *, Moshi NG (1) and UM Minga (2)

* Corresponding author E-mail: kifaro@suanet.ac.tz

(1) Department of Animal Science and Production, Sokoine University Agriculture, P.O. Box 3004, MOROGORO, Tanzania.

(2) Open University of Tanzania The Open University of Tanzania (OUT) was established by an Act of Parliament No. 17 of 1992. It is a single mode institution offering certificate, diploma and degree courses through distance learning. Its Headquarters is situated in Dar es Salaam, Tanzania. , P.O. Box 23409, DAR-ES-SALAAM, Tanzania.
Table 1: Least squares means (LSM [+ or -] SE) of quarter milk yield
(ml) and crude protein content (%) for various factors

                         Variable

Factor             Quarter milk yield

                   n     LSM

Overall            184   136.4 [+ or -] 3.9
CMT -ve            48    146.4 [+ or -] 8.7 (a)
       T           38    175.9 [+ or -] 9.3 (b)
       +1          40    146.3 [+ or -] 9.1 (a)
       +2          34    127.3 [+ or -] 9.1 (ac)
       +3          24    103.4 [+ or -] 9.4 (c)
Parity 1           64    143.1 [+ or -] 7.9
       2           38    151.3 [+ or -] 9.4
       3           34    132.5 [+ or -] 10.6
       4           48    132.6 [+ or -] 7.8
Stage of lact. 1   34    129.4 [+ or -] 11.0 (ab)
       2           94    133.5 [+ or -] 6.1 (a)
       3           56    156.8 [+ or -] 8.3 (b)
Sampling phase 1   108   101.5 [+ or -] 6.7 (a)
       2           76    178.2 [+ or -] 6.8 (b)
Quarter  1         92    138.4 [+ or -] 6.2
       2           92    141.3 [+ or -] 6.2

                         Variable

Factor             Crude protein

                   n     LSM

Overall            81    4.02 [+ or -] 0.08
CMT -ve            21    4.11 [+ or -] 0.21 (ab)
       T           18    3.78 [+ or -] 0.21 (a)
       +1          17    3.61 [+ or -] 0.20 (a)
       +2          14    3.70 [+ or -] 0.21 (a)
       +3          11    4.52 [+ or -] 0.25 (b)
Parity 1           29    3.78 [+ or -] 0.18
       2           19    3.73 [+ or -] 0.20
       3           16    4.06 [+ or -] 0.21
       4           17    4.21 [+ or -] 0.19
Stage of lact. 1   13    3.87 [+ or -] 0.25
       2           27    4.01 [+ or -] 0.12
       3           20    3.95 [+ or -] 0.22
Sampling phase 1   41    4.28 [+ or -] 0.16 (a)
       2           40    3.61 [+ or -] 0.20 (b)
Quarter  1         41    3.89 [+ or -] 0.13
       2           40    4.00 [+ or -] 0.13

CMT = California mastitis test, -ve = Negative CMT score, T = Trace CMT
score, LSM with common superscripts within column within factor were
not significantly different at P>0.05.

Table 2: Least squares means (LSM [+ or -] SE) of butterfat and lactose
for various factors

                         Variable

Factor             Butterfat

                   n     LSM

Overall            87    5.32 [+ or -] 0.13
CMT-ve             24    6.32 [+ or -] 0.30 (a)
T                  20    5.93 [+ or -] 0.30 (a)
       +1          18    4.58 [+ or -] 0.31 (b)
       +2          17    4.86 [+ or -] 0.31 (b)
       +3          8     4.91 [+ or -] 0.45 (b)
Parity 1           31    5.27 [+ or -] 0.27
       2           19    5.43 [+ or -] 0.31
       3           19    5.22 [+ or -] 0.32
       4           18    5.38 [+ or -] 0.29
Stage of lact.1    17    4.59 [+ or -] 0.38 (a)
       2           49    5.22 [+ or -] 0.19 (a)
       3           21    6.16 [+ or -] 0.35 (b)
Sampling phase 1   49    4.30 [+ or -] 0.25 (a)
       2           38    6.35 [+ or -] 0.27 (b)
Quarter  1         43    5.07 [+ or -] 0.21
       2           44    5.60 [+ or -] 0.20

                         Variable

Factor             Lactose

                   n     LSM

Overall            92    3.83 [+ or -] 0.08
CMT-ve             24    4.14 [+ or -] 0.18
T                  20    4.08 [+ or -] 0.19
       +1          19    3.62 [+ or -] 0.19
       +2          17    4.17 [+ or -] 0.19
       +3          12    3.51 [+ or -] 0.24
Parity 1           32    3.78 [+ or -] 0.16
       2           20    4.13 [+ or -] 0.19
       3           19    3.81 [+ or -] 0.20
       4           21    3.91 [+ or -] 0.17
Stage of lact.1    17    4.09 [+ or -] 0.23
       2           52    3.69 [+ or -] 0.11
       3           23    3.93 [+ or -] 0.20
Sampling phase 1   54    3.78 [+ or -] 0.15
       2           38    4.03 [+ or -] 0.16
Quarter  1         47    3.88 [+ or -] 0.12
       2           45    3.93 [+ or -] 0.12

CMT = California mastitis test, -ve = Negative CMT score, T = Trace CMT
score, LSM with common superscripts within column within factor were
not significantly different at P>0.05.

Table 3: Least squares means (LSM [+ or -] SE) of quarter chloride
percentage for the various factors

Factor             N     LSM

Overall             90   0.244 [+ or -] 0.003

CMT -ve             24   0.220 [+ or -] 0.007 (a)
T                   20   0.233 [+ or -] 0.007 (ab)
       +1           18   0.244 [+ or -] 0.007 (b)
       +2           17   0.238 [+ or -] 0.007 (ab)
       +3           11   0.283 [+ or -] 0.009 (c)

Parity 1            32   0.239 [+ or -] 0.006 (a)
       +2           19   0.221 [+ or -] 0.007 (b)
       +3           19   0.249 [+ or -] 0.007 (ac)
       +4           20   0.265 [+ or -] 0.006 (c)

Stage of lact. 1    17   0.248 [+ or -] 0.008
       2            51   0.244 [+ or -] 0.004
       3            22   0.239 [+ or -] 0.008

Sampling phase 1    52   0.276 [+ or -] 0.005 (a)
       2            38   0.212 [+ or -] 0.006 (b)

Quarter 1           46   0.252 [+ or -] 0.005 (a)
       2            44   0.236 [+ or -] 0.005 (b)

CMT = California mastitis test, -ve = Negative CMT score
T = Trace CMT score, LSM with common superscripts within column within
factor were not significantly different at P>0.05.
COPYRIGHT 2009 Rural Outreach Program
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2009 Gale, Cengage Learning. All rights reserved.

 Reader Opinion

Title:

Comment:



 

Article Details
Printer friendly Cite/link Email Feedback
Author:Kifaro, G.C.; Moshi, N.G.; Minga, U.M.
Publication:African Journal of Food, Agriculture, Nutrition and Development
Article Type:Report
Geographic Code:6TANZ
Date:Jan 1, 2009
Words:3578
Previous Article:Maternal knowledge and practices related to anaemia and iron supplementation in rural malawi: a cross-sectional study.
Next Article:Maize growth, yield and soil nutrient changes with N-enriched organic fertilizers.
Topics:


Related Articles
Influence of varying level of sodium bicarbonate on milk yield and its composition in early lactating Nili Ravi buffaloes.
Polymorphism of growth hormone GH1-AluI in Jersey cows and its effect on milk yield and composition.
Prepartum feeding of cationic or anionic diets to Holstein cows given 30 or 60 day dry periods: comparison of dry matter intake, physiological...
Effect of dietary fish oil and soybean oil on milk production and composition of Holstein cows in early lactation.
CAE testing available from BioTracking.
Genetic and environmental trends for milk production traits in sheep estimated with test-day model.
Effect of feeding Ca-salts of fatty acids from soybean oil and linseed oil on c9,t11-CLA production in ruminal fluid and milk of Holstein dairy cows.
Effects of soybean oil or rumen protected conjugated linoleic acid supplementation on accumulation of conjugated linoleic acid in dairy cows' milk.
Influence of varying ruminally degradable to undegradable protein ratio on nutrient intake, milk yield, nitrogen balance, conception rate and days...
Effect of replacing corn silage with whole crop rice silage in total mixed ration on intake, milk yield and its composition in Holsteins.

Terms of use | Copyright © 2014 Farlex, Inc. | Feedback | For webmasters