Fluorine Toxicity and Laying Hen Performance1

Fluorine Toxicity and Laying Hen Performance1 W. GUENTER 2 and P.H.B. HAHN 3 Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Received for publication April 10, 1985)

1986 Poultry Science 65:769-778 INTRODUCTION Fluorine (F), the most reactive halogen, is ubiquitous mainly in the form of inorganic fluoride compounds. The essentiality of trace amounts of F in animal nutrition has been demonstrated (Messer et al, 1972; Schwarz and Milne, 1972). Interest in the role of F in poultry nutrition arose not from deficiency symptoms but rather from toxicity problems induced by feeding raw rock phosphate as a calcium and phosphorus source (Jacob and Reynolds, 1928). Studies by Hauck et al. (1933), Kick et al. (1933), and Phillips et al. (1935) were among the first to evaluate fluo-

1 Funds were supplied by the National Research Council Operating Grant A0457 and the University of Manitoba Grants Commission. 2 To whom requests for reprints should be addressed. 3 Present address: Sure Crop Feeds Ltd., Grindrod, B. C. V0E 1Y0.

ride toxicosis problems in poultry and to suggest various tolerances. The National Research Council (NRC, 1974) report on the effects of fluoride in animals indicated that interpretation of data on the fluoride tolerance of poultry is complicated by the fact that phosphate content as well as fluoride often varied in the experimental diets. Numerous dietary additives or natural components have been evaluated as a means of alleviating fluoride toxicosis in various animal species (NRC, 1974). The mitigating effect of calcium salts has been demonstrated in cattle (Suttie et al, 1957) and rats (Hauck et al, 1933; Peters et al, 1948; Boddie, 1957). Aluminum compounds have been the most frequently used alleviators of fluorosis (Cakir et al, 1978). The mode of action of alleviation has been related to reduction of fluorine absorption. Peters (1971) found increased fecal F excretion with the addition of aluminum phosphate. Although F toxicity in poultry has been studied quite intensely, limited information is

769

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

ABSTRACT Two hundred eighty-eight Single Comb White Leghorn (SCWL) hens were treated for 252 days with sodium fluoride added to a practical wheat-soybean meal-type basal diet to supply 0, 100, 400, 700, 1,000, and 1,300 ppm fluoride (F). On Day 252, hens fed the two highest levels of F were switched to the control diet and the experiment continued for another 168 days. The two highest levels of fluoride resulted in significant (P<.05) depression of feed intake, body weight gain, hen-day production, feed efficiency, and egg quality. Fluoride (700 ppm) tended to reduce performance but generally was not significantly different from the control and lower F diets. Long-term feeding of high levels of F (NaF) did not result in permanent production impairment. Birds fully recovered during the 168-day recovery period. In the second experiment 288 SCWL pullets were treated for 49 days with seven dietary regimens: 0 ppm F fed ad libitum (1), 1,300 ppm F fed ad libitum (2), 0 ppm F control pair-fed to 1,300 ppm F (5), an NaCl diet formulated to supply as much Cl— as F — in diet 3 (4), an NaCl diet formulated to supply as much Na as supplied by NaF in Diet 3, (5), 1,300 ppm F plus 1,040 ppm Al diet fed ad libitum (6), and the same diet pair-fed to the 1,300 ppm F diet (7). All groups were fed the control diet for a 7-day recovery period at the end of the experiment. High F intake significantly (P<.01) decreased feed intake, hen-day production, feed efficiency, and shell quality. However, these depressions were not as severe when Al was present in the diet. The depression in performance due to F feeding was not simply due to the depressed feed intake but rather was a result of a metabolic function of F. Pair feeding the control and F/Al diets resulted in much smaller depression. Egg shell quality was more responsive to the addition of Na to the diet than the F. Although feed consumption recovered within the 7-day recovery period, this time was inadequate for complete recovery in egg production. (Key words: toxicity, fluorine, laying hens)

GUENTER AND HAHN

770

MATERIALS AND METHODS Experiment 1. Two hundred eighty-eight (288) young Shaver Starcross-288 pullets were randomly assigned to 36 cage units (two cages, 40.6 X 40.6 cm/unit) of 8 birds each. Six dietary treatments, consisting of a control (Table 1) and five F diets, were employed. The F diets were prepared by mixing appropriate amounts of basal diet with an F premix (20,000 ppm F) to supply 100, 400, 700, 1,000, and 1,300 ppm F (as NaF). Each dietary treatment was randomly assigned to six replicate cage units and fed for nine 28-day periods. The two groups fed the highest level of F at this time were switched to control feed and the experiment continued for another six 28 days. During the first 252 days, egg production, including numbers of cracks and thin shelled eggs were recorded daily. Feed consumption was recorded on the basis of 28-day periods. Egg weights for all eggs collected over 3 consecutive days in midperiod were recorded for the purpose of calculating average feed efficiency for each period. Bimonthly for 2 consecutive days during midperiod three eggs per day from each cage unit were collected for shell quality (deformation and thickness) and interior quality (Haugh Unit Score) measurements. The effect of dietary F on nutrient retention and plasma levels of Ca and Mg was determined over a 5-day balance trial in period 5. Fifteen kilograms of each experimental diet was mixed with .3% chromic oxide and fed to three replicates of birds from each treatment for 3 days prior to a 48-hr collection of excreta. During the last six 28-day periods, production parameters were measured for all treatments. Experiment 2. The second experiment was designed to study three areas of interest: 1) identification of fluoride toxicosis in laying

hens, 2) examination of the effect of added Na from NaF on laying hen performance, and 3) evaluation of the effectiveness of aluminum sulfate in the prevention of fluoride toxicosis. Two hundred fifty-two 29-week-old Babcock 300V layers were randomly allocated to 42 cage units (two cages of 30 X 40 cm per unit) of 6 birds each. All birds were fed the basal diet (Table 1) ad libitum for 1 week. On Day 8, seven treatments (Table 2) were randomly assigned each to six experimental units and fed for 7 weeks, after which all birds were returned to the basal feed for a 1-week recovery. The seven experimental treatments were as follows: 1) control diet, 2) basal plus 1,300 ppm F from NaF. Both Diets 1 and 2 were fed ad libitum. To quantify the effect of reduced feed intake due to fluorine feeding, a third treatment was introduced (3). Hens in this group were pair-fed the basal diet to match the mean previous days intake of hens fed

TABLE 1. Composition of basal diets used in fluorine experiments Ingredients (g/kg) G r o u n d wheat G r o u n d oats S o y b e a n meal (44%) Alfalfa meal (17%) G r o u n d limestone Dicalcium p h o s p h a t e Oyster shell Vitamin p r e m i x 1 Mineral p r e m i x ' Animal tallow

400 300 151 20 54 5 25 10 5 30

Chemical analysis (as fed)

Experiment 1

Crude protein, % Crude fat, % Ca, % P (total), % F, ppm Metabolizable energy, MJ/kg

15.7 5.1 3.14 .55

1

11.002

Experiment 2 16.3 4.9 3.51 .57 16.2 11.23

The vitamin and mineral premixes supplied per kilogram ration: 8,260 IU vitamin A; 880 IU vitamin D 3 ; 5.5 IU vitamin E; 11 g vitamin B , 2 ; 5.5 mg riboflavin; 11 mg calcium pantothenate; 27.5 mg niacin; 275 mg choline; .5 g DL-methionine; 4.7 g iodized NaCl; 33 mg Mil; 14.3 mg Zn, 30.8 mg Fe ; 2.53 mgCu. 2

Calculated.

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

available on long-term feeding of F diets to laying hens (Michel et ai, 1984). Two experiments were designed, first, to determine the effect of long-term feeding of various levels of F on laying hen performance and, second, to evaluate the effectiveness of aluminum sulphate in preventing F toxicosis in laying hens. These experiments were conducted during the time of extensive discussion of the environmental hazard posed by a proposed installation of an aluminum smelter in Manitoba.

FLUORINE TOXICITY AND HEN PERFORMANCE

771

TABLE 2. Composition of dietary treatments (Experiment 2) Treatment composition Dietary treatment

Basal

Fluorine 1 premix

Aluminum 2 premix

NaCl3 premix

(g/kg) Control 1,000 1,300 p p m F 935 Pair-fed control NaCl (Cl/F) 4 935 NaCl (Na/Na) s 879 1,300 ppm F/l,040 ppmAl 883 Pair-fed 1,300 ppm f/l ,040 ppm Al

0 65

0 0

0 0

0 0 65

0 0 52

65 121 0

1

Fluorine premix supplies 20,000 mg/kg premix: 955.8 g basal diet + 44.2 g NaF (powder).

2

Aluminum sulphate premix supplies 20,000 mg Al/kg premix: 753 g basal diet + 247 g Al2 (SO„) 3 - I S H J O .

3

Sodium chloride premix supplied 20,000 ppm Cl/kg premix: 967 g basal diet plus 33 g NaCl.

4

Chlorine content formulated to match F in Treatment 2.

5

The Na + content to match Na + content in Treatment 2.

1,300 ppm F. The effect of the Na component of the added NaF was examined by feeding the basal ration supplemented with either of two concentrations of NaCl. The first NaCl ration 4) was formulated to match the anion content of the 1,300 ppm F ration by substituting Cl— for F — on a ppm basis (1,300 ppm CI). The second NaCl treatment (5) was formulated to match the cation content of treatment 2 (1,573 ppm Na). Both Diets 4 and 5 were provided ad libitum. Diets 6 and 7 were assigned to examine if aluminum sulfate added to the high F ration had any effect. Both treatments contained 1,300 ppm F plus 1,040 ppm Al to give a ratio of 1 F : .8 Al suggested by Cakir et al. (1978) for chicks and poults. Treatment 6 birds were fed ad libitum, whereas Treatment 7 birds were pair-fed the ration to match the previous day's mean feed consumption of hens fed 1,300 ppm F (Treatment 2). Daily feed consumption, mortality, egg production, and uncollectable eggs (cracked and soft shelled) were recorded. Six eggs per cage unit were collected at the start of the 1st, 2nd, 3rd, and 8th week of the experiment for measurements of egg quality as described in Experiment 1. Both experiments were conducted in an environmentally controlled house under 14 hr of daylight. Filtered tap water (1 ppm F) was provided ad libitum. All diets were fed in a mash form and wire screens were placed on top of the feed in the troughs to minimize spillage of feed by the hens.

Proximate analysis for dry matter, ether extract, energy, and ash were determined using procedures published by the Association of Official Chemists (AOAC, 1975). Calcium, P, Mg, and Cr were determined following procedures listed in AOAC (1975) and Analytical Methods for Atomic Absorption Spectrophotometry (Perkin Elmer Corp., 1973). In Experiment 2, F content of the water source and basal diet was determined using a Fisher Acumet Model 750 pH/Ion Meter equipped with an Orion 96-09 fluoride ion specific electrode, according to the method of Villa (1979). Experimental data were analyzed by procedures described by Snedecor and Cochran (1967). A Statistical Package for the Social Sciences (SPSS) Subprogram ANOVA (Nie et al., 1975) and a Biomedical Computer Program PIV (one-way ANOVA) (BMDP, 1979) were computer packages used to apply analysis of variance testing. Multiple comparisons among means were made using Tukey's Test (Steel andTorrie, 1960).

RESULTS AND DISCUSSION

Excessive fluoride ingestion can induce either an acute toxicosis or a debilitating chronic condition often referred to as chronic fluoride toxicity, fluoride toxicosis, or fluorosis (NRC, 1974).

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

1. 2. 3. 4. 5. 6. 7.

772

GUENTER AND HAHN

-

3t

/^

\^

-x-—"''^

A. /

-

•

*

'

-o

,^-4 .

•

-

•

•

A.-4

*

CONTROL .

r \ v-' ^-«/

v

v

•' V

A4

.*=s^ •'""C^

'

N /

—X Control

»

A- — A 1000 ppm F o - —O 1300 ppm F

6

8

10

12

PERIODS (28 DAYS)

FIG. 1. Feed intake for control and birds fed high fluorine (Experiment 1).

Experiment 1. Average feed consumption for the control birds, although not significant, was slightly greater than for those fed diets containing 100 and 400 ppm F (Table 3). Significant (P<.05) depression in feed intake was observed for each additional 300 ppm F. These results are in agreement with previous findings of Phillips et al. (1935), Gardiner et al. (1968), and Van Toledo and Combs (1984). Contrary to the findings of Van Toledo and Combs (1984), hens fed the high F (1,300 ppm) diets did not recover from their depression in feed intake with time (Fig. 1); however, a general trend toward recovery was noted for the group fed 1,000 ppm F. An interesting phenomenon was observed with hens fed 400 and 700 ppm F (Fig. 3). Although these levels were not considered to be toxic, feed consumption declined severely at intervals. It was suspected that F in plasma slowly built

Feed efficiency (Table 3) was not affected by up to 700 ppm F, although the group fed 700 ppm tended to show lower efficiency. Higher F resulted in poorer (P<.05) feed conversion. The lower feed efficiency was probably due to the lower intake and a greater proportion of the feed being required for body maintenance. The higher F diets also tended to yield lower metabolizable energies (ME) in spite of increased (P<.05) fat retention (Table 5). Gardiner et al. (1968) demonstrated that fluoride-fed chicks were less efficient in converting ME to gain, which was attributed to an alteration in metabolism.

TABLE 3. Production response of laying hens fed various levels of dietary fluorine for 252 days, (Experiment 1) Dietary treatment

Average feed intake

(ppm F) 0 100 400 700

1,000 1,300 SE

Body gain

Hen-day production

Feed efficiency

Mortality

(g/hen/day)

(g/hen)

(%)

(g/g egg)

(%/month)

120 d 114 c d 112cd 109 c

290 b 250 b 220 b 180 b

82d 81d

97b 78a 2.5

a

2.38 a 2.36 a 2.39 a 2.58 a 3.37 b 4.77 c

.7 .7 .7 1.2 2.3 2.8

10 20a 21

79cd

71c 51b 31a 2.1

.12

Means within a column not followed by the same superscript are significantly different (P<.05).

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

1 4

up to a level high enough to result in sudden appetite depression and birds gradually recovered as F cleared from plasma. Simon and Suttie (1968) found that dietary F depressed feed consumption in rats when plasma F increased to 3 ppm, but after a period of reduced feed intake, feed consumption returned to normal. Parallel to the reduction in feed intake, body weight gain over the entire period gradually declined as the F in the diet increased to 700 ppm. Additional F resulted in significantly (P<.05) lower gains (Table 3). Similarly, egg production declined (Figs. 2 and 3) for hens fed increasing levels of F. The reduction in weight gain and egg production appeared to be mainly due to the reduced feed intake. Weight gain decreased more rapidly than egg production, suggesting that yolk synthesis had priority over tissue deposition when nutrient availability was limited. Although reduction in egg size (Table 4) was significant (P<.05) at 1,000 and 1,300 ppm F, the depression was only 8% compared with a 35% reduction in feed intake and a 72% reduction in production.

773

F L U O R I N E T O X I C I T Y A N D HEN P E R F O R M A N C E

100

x

-

K Control

A--—A lOOOppm F O o I300ppm F 80

g

«

H O O O or o.

-A..

~<>-~

'•A-..

A-

I

700pprr F

-
-A.

V

>\s //

-

o

A

A.

60

Q O

60

X lOOppm F 4 0 0 ppn F

o- — - O o- .-o-^

120

_&.-

a-

-CKT^9

V •

*

=

*

no <-

;

\- ^

V

100 - -

,

l 0

2

4

6

9

10

12

O <

, , ,

•

so a" Ll_

6 8 10 PERIODS (28 DAYS)

80

FIG. 3. Feed intake and egg p r o d u c t i o n for birds fed low and i n t e r m e d i a t e fluorine ( E x p e r i m e n t 1).

PERIODS (28 DAYS) FIG. 2. Egg p r o d u c t i o n for control and birds fed high flourine ( E x p e r i m e n t 1).

T A B L E 4. Response

Dietary treatment

Egg weight

( p p m F)

(g) C

61.8 60.6bc 60.9bc 60.3bc 58.5ab 56.3a .69

0 100 400 700 1,000 1,300 SE a,b,c

of egg quality parameters

Haugh units

ab

82 81a 81a 84abc gybe 88e 1.0

to dietary fluorine

(Experiment

1)

Shell strength

Uncollectable

Deformation

Thickness

(Mm)

(mm)

a

b

28.5 26.6a 27.9a 29.0a 36.2b 35.lb .99

(%) 42a l9a 64ab 74ab 92bc

.354 .361b .356b .352b .330a .326a .003

1 75c 006

Means within a column n o t followed b y the same superscript are significantly different ( P < . 0 5 ) .

T A B L E 5. Effect

of dietary

levels of fluorine on nutrient retention and plasma calcium and levels (Period 5, Experiment 1)

magnesium

Retention Dietary treatment

ME n >

( p p m F)

(MJ/kg)2

0 100 400 700 1,000 1,300 SE

10.32ab 10.54ab 10.40ab 10.78b 10.22ab 9.33a .30

Ether extract

Plasm a Calcium

Phosphorus

Ca

58bc 71 = 46abc

5a 38ab 30ab

36ab 45abc 19a 6.8

46b 18ab

2.6b 2.6b 2.3b 1.9 a b 2.0ab 1.4 a .16

Mg -Kmg/d

86a 9jb 92b 94b 9lb 95b 1.0

20ab 7.1

' ' Means within a column not followed by t h e same superscript are significantly different ( P < . 0 5 ) . 1

Nitrogen-corrected metabolizable energy.

2

4 . 1 8 4 J = 1 cal.

.30ab .32b .3lb .25a .28ab .24a .016

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

1

GUENTER AND HAHN

t^ i n vo i - N H rfi M H ' t Ov IH

D O N f t t f' t « CO t 00 (N " CO M

t

>ON W W

O m

rt rt rt a) .O rt rn m m 00 O ON t-- t-~ t^ t-~ co r^

c-j NO f n i n TJ- m r*i m fft ^ - i - ' t m NO NO NO NO NO NO

GO

t n ^t- ON ^

CN

rf

oq NO r^- NO NO r> o_ oi r4 (NJ ci
o

o o\m « m in « 't N t [^ ^ 6 NO NO NO NO C^ t ^

rt

rt

rt

rt

H

X I cd

10 C

C

_ o o -g o u h o o o o o £ 0 0 0 0 0 O -1 * f» O m

U

12 DAY

16

18

20

22

FIG. 4. Effect of dietary fluorine (NaF) and aluminum (Al2 (SO„) 3 •ISHjO) on daily feed intake of laying hens (Experiment 2). w

r-T rt CA

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

O O ON O m CO CS m in ^- in rr* *& © m r*i m fn m m o

A positive relationship was noted between mortality and dietary F. Although the mortality data (Table 3) were not statistically analyzed, the results suggest that F above 400 ppm in the diet may interfere with birds' resistance to common diseases. Autopsies of birds that died did not show signs of F toxicity; however, birds consuming diets containing 700 ppm or higher F had increased mortalities due to other causes. Loss of feathers or diarrhea, as described by Buchner et al. (1929) and Van Toledo and Combs (1984), were not conditions observed in this study. Concurrent with the decrease in egg size (Table 4) was a general trend for better (P<.05) interior quality (Haugh unit score) at higher F intake. However, shell quality (deformation and thickness) declined (P<.05) as dietary F increased, resulting in a greater (P<.05) incidence of uncollectable (cracked and thin shelled) eggs. this suggests that either the Ca intake of hens fed the high F diets was inadequate to maintain good shell quality or F inhibited Ca metabolism in the hen. Chang et al. (1977) reported that urinary Ca excretion increased in rats fed 200 ppm F, resulting in less Ca available for bone formation. A general trend in reduced Ca retention (P<.05 at high F) and plasma Ca (P<.05) was observed (Table 5). No consistent response was apparent for phosphorus retention or plasma magnesium levels, although the latter tended to be lower for birds fed diets containing more than 400 ppm F. The data for the recovery period (Table 6) indicates no treatment differences for any of the parameters except feed intake and Haugh unit score. The 1,000 ppm treatment group rapidly (P<.05) increased its feed intake

FLUORINE TOXICITY AND HEN PERFORMANCE

775

TABLE 7. Effect of dietary fluorine and aluminum treatments on feed intake, feed conversion, and egg production (Experiment 2) Treatment period (7 weeks)

Postexperirr lental (1 week) Hen-day

Hen-day Dietary treatment

Feed intake

Feed conversion

egg

(%)

111.9 71.4 A 71.4A

(g/g e gg) 2.22 A 3.59 B 2.34A

88.5 D 38.5A 56.7B

(g/bird/day) 112.3AB 100.9 A 123.4B

86.5° 44.5A 54.4AB

106.7 C

2.33A

83.0 D

107.3 A

80.3CD

106.6 C

A

81.5CD

IO6.4A

73.8BCD

95.6 B 71.4A

2.50 A 2.66 A

69.5 C 50.5AB

109.2AB 112.QAB

75.0BCD 62.1ABC

1.49

.130

2.33

2.86

(g/bird/day)

SE

A—D Means within a colu

2.36

egg

production

(%)

4.07

mn followed b y different superscripits are significant:ly different (P<.01).

relative to the groups fed 100 and 400 ppm F (Table 6, Fig. 1). Hens switched from the 1,000 and 1,300 ppm F diets to the control diet and the birds fed the 700 ppm F diet continued to produce eggs with better (P<.05) Haugh unit scores. Treatments did not influence mortality percentages. The results from this first experiment suggest that hens over a feeding period of 420 days are relatively insensitive to dietary F of 700 ppm or less. Higher F results in significant depression of feed intake and performance; however, quick recovery resulted when birds, after consuming 1,000 or 1,300 ppm F for 252 days, were fed the control diet. This result suggests that the effects are not permanent. Experiment 2. The second experiment was conducted to determine whether feed intake depression alone was the factor responsible for the poor performance of hens fed 1,300 ppm F in their diets. The rapid decline (44% on Day 1) in feed intake of 1,300 ppm F treatment group (Fig. 4), which reached a minimum on Day 3, did not appear to be a palatability problem. Hens fed the identical diet with added Al had significantly (P<.05) higher feed intakes, which suggests that taste of NaF in the diet was not the problem or that the aluminum sulfate masked the NaF taste. It is possible that some of the depression in feed intake was due to gastric or intestinal irritation by NaF. Decka

et al. (1978), in human studies, was able to demonstrate that elevated F doses caused gastric irritation which could be reduced by administering supplemental aluminum. Early studies by Phillips et al. (1935) had shown that the effects of dietary F on feed intake were systemic in nature. This study suggests that circulating F in the blood affects the appetite centers in the brain. Such depressing action of F had previously been postulated by Suttie (1968) and Weber et al. (1969). Suttie suggested that increased F in the blood caused alterations in production of certain metabolites that affected depressed appetite. Intake after 3 days fluctuated considerably throughout the first 21 days and stabilized at an average of 71 g/hen per day. This gradual increase in feed intake after the initial decline was similar to that reported by Van Toledo and Combs (1984) for laying hens and Suttie (1968) for rats. It appeared that birds could adapt to the F intake over a short period, but consumption again decreased if F feeding continued. Addition of NaCl to the control diet to match NaF-supplemented rations on a Cl/F or Na/Na basis had no effect on feed intake (Table 7). Feed intakes of the pair fed control and pair fed F/Al groups increased faster than for the 1,300 ppm F group during the recovery period. Because feed intakes required several days for the 1,300 ppm group to increase to levels equal

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

1) Control 2) 1,300 ppm F 3) Control Pair-fed 4) NaCl (Cl/F) 5) NaCl (Na/Na) 6) 1,300 ppm F/1,040 p p m Al 7) 1,300 ppm F/1,040 p p m Al Pair-fed

C

production

Feed intake

59.4 55.8 57.3

57.9

58.5

57.8 55.7 1.15

57.1

56.8

56.8 55.7

1.05

(g)

Week 7

58.1 55.9 54.6

Week 2

Egg wei ight

27.5 31.3

81.0 84.5

1.54

83.2 83.4

'Pair-fed to match previous day mean feed consumption of hens fed 1,300 ppm F.

2.41

29.2

82.3

1.31

28.4

83.7

86.4 85.3

25.3 33.4 25.1

Week 2

82.3 83.1 82.9

Week 7 • (M

Shell de

82.7 81.6 83.7

Week 2

Haugh units

a,b Means within a column followed by different superscripts are significantly different (P<.05).

SE

1) Control 2) 1,300 ppm F 3) Control Pair-fed1 4) NaCl (Cl/F) 5) NaCl (Na/Na) 6) 1,300 ppm F / l , 0 4 0 p p m Al 7) 1,300 ppm F/520 ppm Al Pair-fed1

Dietary treatment

TABLE 8. Effect of dietary fluorine and aluminum treatment on egg quality (E

http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

FLUORINE TOXICITY AND HEN PERFORMANCE

Although hen-day egg production of the 1,300 ppm F treatment group recovered significantly (Table 7) during postexperimental recovery, production remained lower than the former pair-fed controls. Further research is required to determine if F released during bone resorption has a negative effect on egg production. Circulating F may also depress follicle development, resulting in slower recovery. The lack of complete recovery for the pair-fed hens may be due to a lack of mature ova as a result of inadequate nutrient intake. Burke (1977) suggested that the final phase of follicle development requires 9 to 11 days; however, the recovery period was only 7 days in this study. Feed conversion progressively worsened with time of feeding the 1,300 ppm F ration. A major factor affecting the feed conversion ratio was the steady decline in egg production associated with the high F diet (Table 7). Because feed conversion of the pair-fed controls and the F/Al treatment groups were not significantly (P>.01) different from the control group but significantly (P<.01) better than the 1,300 ppm F-treated hens, it was evident that the toxic effects of F on feed conversion were not solely due to the reduced nutrient intake of these hens resulting in a greater proportion

being required for maintenance. Other factors, such as poor nutrient absorption and metabolic utilization, must play a role. The addition of NaCl to the control diet had no effect on feed consumption, egg production, or feed efficiency. Egg quality (Table 8), contrary to Experiment 1 findings, was not affected by the 1,300 ppm F treatment. Consideration should be given to the fact that this study was of short duration. Similar findings were reported by Merkley (1981) and Van Toledo and Combs (1984). However, Kuhl and Sullivan (1976) reported a significant (P<.05) reduction in shell breaking strength when 500 ppm F were fed for 16 weeks. Sodium chloride treatments appeared to exert a more pronounced effect on shell thickness and deformation than the F treatment (Table 8). Kuhl and Sullivan (1976) noted that when monosodium phosphate was added to a 500 ppm NaF ration fed to laying hens, shell strength decreased. Monosodium phosphate contains 19.1% Na (Hubbell, 1979), and therefore, the response may have been due to added Na. This Na percentage raises the question as to whether the long-term effect on shell quality observed in Experiment 1 from feeding NaF was due to the added Na rather than the F. Sodium mediates the effect through acidbase change (Mongin, 1980). Cohen et al. (1972), however, suggested that acid-base parameters are only affected if Na + is added without Cl~. REFERENCES Allcroft, R., and K. N. Burns, 1969. Alleviation of industrial fluorosis in a herd. Fluoride 2:55—59. Association of Official Analytical Chemists, 1975. Official methods of analysis. 12th ed., Washington, DC. Boddie, G. F., 1957. Fluorine alleviators. II. Trials involving rats. Vet. Rec. 72:441—445. BMDP Statistical Software, 1979. Univ. California Press, Berkeley. Buckner, G. D., J. H. Halpin, and W. M. Insko, Jr., 1929. The relative utilization of certain calcium compounds by the growing chick. Poultry Sci. 9:1-5. Burke, W. H., 1977. Avian reproduction. Pages 825 — 842 in Duke's Physiology of Domestic Animals 9th ed. Melvin Swenson, ed. Cornell Univ. Press, Ithaca, NY. Cakir, A., T. Sullivan, and F. Mather, 1978. Alleviation of fluorine toxicity in starting turkeys and chicks with aluminum. Poultry Sci. 57:498—505. Chang, Y.-O. M. Pan, and T. Uarnell, 1977. The effect of fluoride on calcium absorption in rats. Nutr. Rep. Int. 16:539-547.

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

to the controls, it is suggested that circulating F remained high enough for several days to inhibit appetite. However, if gastric irritation was a factor, a time of recovery may also have been required. High dietary F-induced decreases in egg production were not as rapid as that of feed intake (Table 7). This result suggested that the hens had sufficient body stores to initially meet the demands for egg production and the production-depressing effect of F resulted in a slower prolonged ova development due to a nutrient deficiency. However, this result only explains part of the depression, because the pair-fed groups, at similar intakes, produced eggs at higher rates. High circulating F may have an effect on yolk material synthesis. The addition of Al to the high F diet tended to delay the suppressive effect of F on production. Allcroft and Burns (1969) reported that alminum sulfate was a short-term F toxicity alleviator in that it delayed fluoride accumulation but did not prevent it. Cakir et al. (1978) demonstrated with colostomized turkeys that the mode of action of aluminum sulfate was by binding free fluoride ions in the gut, thereby reducing F absorption.

777

778

GUENTER AND HAHN and D. H. Bent, 1975. Statistical Package for the Social Sciences (SPSS). 2nd ed. McGraw-Hill Book Co., New York, NY. Perkin Elmer Corporation, 1973. Analytical methods for atomic absorption spectrophotometry. Perkin Elmer Corp. Peters, J. H., L. Geeman, and T. S. Danowski, 1948. Beneficial effects of calcium chloride in fluoride poisoning. Fed. Proc. 7:92—93. Peters, L. H., 1971. The effect of aluminum phosphate on the gastrointestinal absorption of fluoride from diets containing fish protein concentrate or casein. Diss. Abstr. Int. Ser. B31:3844-3845. Phillips, P. H., J. G. Halpin, and E. B. Hart, 1935. The influence of chronic fluorine toxicosis in laying hens upon the fluorine content of the egg and its relation to the lipid content of the egg yolk. J. Nutr. 10:93-98. Schwarz, K., and D. B. Milne, 1972. Fluorine requirements for growth in the rat. Bioinorg. Chem. 1:331. Simon, G., and J. W. Suttie, 1968. Effect of dietary fluoride on food intake and plasma fluoride concentration in the rat. J. Nutr. 96:152—156. Snedecor, G. W., and W. G. Cochran, 1967. Statistical Methods. 6th ed. Iowa State Univ. Press, Ames. Steel, R. G., and J. H. Torrie, 1960. Principles and Procedures of Statistics. McGraw Hill Inc., New York, NY. Suttie, J. W., 1968. Effect of dietary fluoride on the pattern of food intake in the rat and development of a programmed pellet dispenser. J. Nutr. 96:529-536. Suttie, J. W., R. F. Miller, and P. H. Phillips, 1957. Effects of dietary sodium fluoride on dairy cows. I. The physiological effects and the development symptoms of fluorosis. J. Nutr. 63:211 —224. Van Toledo, B., and G. F. Combs, Jr., 1984. Fluorosis in the laying hen. Poultry Sci. 63:1543-1552. Villa, A., 1979. Rapid method for determining fluoride in vegetation using an ion-selective electrode. Analyst 104: 5 4 5 - 5 5 1 . Weber, C. W., A. Doberenz, and B. Reid, 1969. Fluoride toxicity in the chick. Poultry Sci. 48: 230-235.

Downloaded from http://ps.oxfordjournals.org/ at University of Pennsylvania Library on January 18, 2015

Cohen, I., S. Hurwitz, and A. Bar, 1972. Acid-base balance and sodium-to-chloride ratio in diets of laying hens. J. Nutr. 102:1-8. Decka, R., S. Kacker, and G. Shambaugh, 1978. Intestinal absorption of fluoride preparations. Laryngoscope 88:1918-1921. Gardiner, E. E., K. Winchell, and R. Hironaka, 1968. The influence of dietary sodium fluoride on the utilization and metabolizable energy value of a poultry diet. Poultry Sci. 47:1241-1244. Hauck, H. M., H. Steenbock, and H. T. Parson, 1933. The effect of the level of calcium intake on the calcification of bones and teeth during fluorine toxicosis. Am. J. Physiol. 103:489-493. Hubbell, C. H., 1979. 1979 Feedstuffs analysis table. Feedstuffs, Minneapolis, MN. Jacob, K. D., and D. S. Reynolds, 1928. The fluorine content of phosphate rock. Assoc. Offic. Anal. Chem. 11:237-250. Kick, C. H., R. M. Bethke, and P. R. Record, 193 3. Effect of fluorine in the nutrition of the chick. Poultry Sci. 12:382-387. Kuhl, H. J., and T. W. Sullivan, 1976. Effect of sodium fluoride and high fluorine fertilizer phosphates on performance of laying chickens and egg shell quality. Poultry Sci. 55:2055. (Abstr.) Messer, H. H., W. D. Armstrong, and L. Singer, 1972. Fertility impairment in mice on a low fluoride intake. Science 177:893-894. Merkley, J. W., 1981. The effect of sodium fluoride on egg production, egg quality, and bone strength of caged layers. Poultry Sci. 60:771—776. Michel, J. N., J. W. Suttie, and M. L. Sunde, 1984. Fluorine deposition in bone as related to physiological state. Poultry Sci. 63:1407-1411. Mongin, P., 1980. Electrolytes in nutrition: A review of basic principles and practical application in poultry and swine. Proc. 3rd Annu. Int. Min. Conf., Orlando, FL. National Research Council, 1974. Effects of Fluorides in Animals. Committee on Animal Nutrition. Subcommittee on Fluorosis. Natl. Acad. Sci., Washington, DC. Nie, N. H., C. H. Hull, J. G. Jenkins, K. Steinbrenner,