Table 2.

Diseases and health problems on the broiler farm

			Effect on business economics1
Disease	Cause	Effect on efficiency/production	Mortality	Growth	Feed	Prevention	Treatment
Respiratory
Infectious bronchitis2	Coronavirus2	Mortality due to suffocation2	++3	-3	-3	Vaccination, hygiene2	Good housing conditions and extra heating4,5
						All-in, all-out system
Immune organs
Infectious bursal disease6	Virus6	Mortality7,8,9	+7,8	-9	-9	Vaccination10,11,12	No5,12
		Reduced feed and water intake
Gastrointestinal
Coccidiosis13	Eimeria acervulina14,15	Weight loss16	+17	–18,19	++18,19	Vaccination20,21,22	Chemotherapy
	Eimeria maxima14,15	Reduced growth rate				Anticoccidial drugs in feed	Remove wet litter
	Eimeria tenella14,15	Mortality				Hygiene (disinfectant)
		Increased feed conversion
Escherichia coli (including peritonitis)23	E. coli23	Mortality	+24	-25	-26	Hygiene23,27	Antibiotics26
						Good ventilation
Necrotic enteritis28	Clostridium perfringens type C	Mortality19,29	+	-12	0	Adjusted feed composition	Antibiotics5
						Prevention of coccidiosis
						General hygiene5
						10% solution formalin
						Pre- and probiotics
Locomotion
Leg problems30,31,32	Genetic predisposition33	Skin irritation and blisters, footpad dermatitis and hock burn	0	-34	0	Various management factors such as limiting feed, meal feeding, and lighting schedule31,35,36,37	No
	Metabolic disorders Feed composition Lack of movement
				Reduced feed intake
Heart and vascular
Ascites38	Selection	Condemnation38	++39	0	0	Slower growth rate30	No
		Mortality				Feed with a lower energy content
Sudden death syndrome40	Selection	Mortality	++41	0	0	Slower growth rate42,43,44	No
					Feed with a lower energy content

¹– = much lower; - = lower; 0 = equal; + = higher; ++ = much higher. Effect is compared with the healthy situation.

²Cavanagh, 2003.

³Yohannes et al., 2012.

⁴Lopez et al., 2006.

⁵KWIN-V, 2011.

⁶Lasher and Shane, 1994.

⁷Sanchez et al., 2005.

⁸Cavanagh, 1992.

⁹McIlroy et al., 1989.

¹⁰BCFI, 2012.

¹¹McIlroy et al., 1992.

¹²Saif et al., 2003.

¹³Ruff, 1999.

¹⁴Graat et al., 1996.

¹⁵Haug et al., 2008.

¹⁶Voeten, 2000.

¹⁷Williams, 1999.

¹⁸Williams, 1998.

¹⁹Voeten et al., 1988.

²⁰Wheelhouse et al., 1985.

²¹Vermeulen et al., 2001.

²²Steenhuisen and Vossen, 2001.

²³Kabir, 2010.

²⁴Rahman et al., 2004.

²⁵Tian and Baracos, 1989.

²⁶Fernandez et al., 1998.

²⁷Dziva and Stevens, 2008.

²⁸McDevitt et al., 2006.

²⁹Brigden and Riddell, 1975.

³⁰Julian, 2005.

³¹Estévez, 2007.

³²De Jong et al., 2012.

³³Manning et al., 2007.

³⁴Weeks et al., 2000.

³⁵Su et al., 1999.

³⁶Fanatico et al., 2005.

³⁷Knowles et al., 2008.

³⁸Olkowski et al., 1996.

³⁹De Smit et al., 2005.

⁴⁰Newberry et al., 1987.

⁴¹Julian, 1998.

⁴²Havenstein et al., 1994.

⁴³Van Horne et al., 2003.

⁴⁴Bricket et al., 2007.